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Tire-Pavement Friction Characteristics with Elastic Properties of Asphalt Pavements

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The skid-resisting performance of pavement is a critical factor in traffic safety. Recent studies primarily analyze this behavior by examining the macro or micro texture of the pavement. It is inevitable that skid-resistance declines with time because the texture of pavement deteriorates throughout its service life. The primary objective of this paper is to evaluate the use of different asphalt pavements, varying in resilience, to optimize braking performance on pavement. Based on the systematic dynamics of tire-pavement contact, and analysis of the tire-road coupled friction mechanism and the effect of enlarging the tire-pavement contact area, road skid resistance was investigated by altering the elastic modulus of asphalt pavement. First, this research constructed the kinetic contact model to simulate tire-pavement friction. Next, the following aspects of contact behaviors were studied when braking: tread deformation in the tangential pavement interface, actual tire-pavement contact in the course, and the frictional braking force transmitted from the pavement to the tires. It was observed that with improvements in pavement elasticity, the actual tire-pavement contact area increased, which gives us the ability to effectively strengthen the frictional adhesion of the tire to the pavement. It should not be overlooked that the improvement in skid resistance was caused by an increase in pavement elasticity. This research approach provides a theoretical basis and design reference for the anti-skid research of asphalt pavements.
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applied
sciences
Article
Tire-Pavement Friction Characteristics with Elastic
Properties of Asphalt Pavements
Miao Yu 1,2,*, Guoxiong Wu 3,*, Lingyun Kong 1and Yu Tang 1
1National and Regional Engineering Lab for Transportation Construction Materials,
College of Civil Engineering, Chongqing Jiaotong University, 66 Xuefu Ave, Nanan Qu,
Chongqing 400074, China; klyyqr2002@163.com (L.K.); faye-yu@163.com (Y.T.)
2Highway School, Chang’an University, Middle-Section of Nan’er Huan Road, Xi’an 710064, China
3Chongqing Jianzhu College, 857 Lihua Ave, Nanan Qu, Chongqing 400072, China
*Correspondence: yumiaoym@126.com (M.Y.); wgx_ph.d@163.com (G.W.);
Tel.: +86-023-62789023 (M.Y.); +86-023-61849988 (G.W.)
Received: 16 September 2017; Accepted: 26 October 2017; Published: 1 November 2017
Abstract:
The skid-resisting performance of pavement is a critical factor in traffic safety. Recent
studies primarily analyze this behavior by examining the macro or micro texture of the pavement.
It is inevitable that skid-resistance declines with time because the texture of pavement deteriorates
throughout its service life. The primary objective of this paper is to evaluate the use of different
asphalt pavements, varying in resilience, to optimize braking performance on pavement. Based
on the systematic dynamics of tire-pavement contact, and analysis of the tire-road coupled friction
mechanism and the effect of enlarging the tire-pavement contact area, road skid resistance was
investigated by altering the elastic modulus of asphalt pavement. First, this research constructed
the kinetic contact model to simulate tire-pavement friction. Next, the following aspects of contact
behaviors were studied when braking: tread deformation in the tangential pavement interface, actual
tire-pavement contact in the course, and the frictional braking force transmitted from the pavement
to the tires. It was observed that with improvements in pavement elasticity, the actual tire-pavement
contact area increased, which gives us the ability to effectively strengthen the frictional adhesion of
the tire to the pavement. It should not be overlooked that the improvement in skid resistance was
caused by an increase in pavement elasticity. This research approach provides a theoretical basis and
design reference for the anti-skid research of asphalt pavements.
Keywords: skid-resistance; asphalt pavement; tire; friction; contact area; braking force coefficient
1. Introduction
Skid resisting performance is the primary factor affecting traffic safety, specifically during vehicle
braking where the anti-skid deficiencies found in pavement will prolong braking time and increase
braking distance [
1
]. Due to this concern, highway authorities and researchers have been exploring the
anti-skid properties of pavement through the frictional contact analyses of three key factors.
The first factor is water. In the early 1960s, Horne and Dreher 1963 [
2
] put forward the famous
National Aeronautics and Space Administration (NASA) hydroplaning equation, which is used to
calculate the hydroplaning speed of a tire. Later, Martin 1966, Eshel 1967, and Tsakonas et al. 1968 [
3
5
]
also simulated the hydroplaning of a tire, but in only two dimensions. In the following thirty years, both
the NASA equation and the two-dimensional contact model were promoted by Horne et al. 1986 [
6
]
on the applicable conditions and accuracy. In the 21st century, a three-dimensional frictional model of
inflated tire and rigid pavement contact, simulating moist conditions, was developed by G.P. Ong et al.
2007, 2008, 2010, 2012 [
7
10
]. With this model, the degradation mechanism of wet-pavement skid
Appl. Sci. 2017,7, 1123; doi:10.3390/app7111123 www.mdpi.com/journal/applsci
Appl. Sci. 2017,7, 1123 2 of 16
resistance and the subsequent effects of tire slip velocity on rigid pavement under different degrees of
wetness were examined.
The second factor is the frictional property of tire rubber. The friction between tire and pavement
is mainly determined by adhesive and hysteretic friction. Hysteric friction is enhanced with rise
in temperature. For this analysis, K.A. Grosch 2001 [
11
] chose to use the rubber friction model
based upon the tire rubber’s viscoelasticity. Coupling thermos-mechanics with the finite element
method, Srirangam and Anupam 2013 [
12
,
13
] estimated the variations in hysteretic friction during
tire-pavement contact due to differences in temperature. This estimation was calculated by simulating
a tire rolling on rigid pavement in CAPA-3D (developed and dated by the group of Mechanics of
Infrastructure Materials at Delft University of Technology, The Netherlands) Finite Element system.
The third final component in exploring the anti-skid properties of pavement is the surface texture
of the pavement. Both the macro-texture and micro-texture are typically used to represent the skid
resistance of pavement. The correlation between pavement texture and skid resisting ability are often
evaluated via various test methods (Forster, S. W. 1990, Burak Sengoz 2014, Malal Kane 2015 [
14
16
]).
For instance, Srirangam and Anupam 2013 [
12
,
13
] captured morphological data reflecting the surface
of asphalt pavement through X-ray tomography. Furthermore, they reconstructed the texture of the
pavement in CAPA-3D and analyzed their simulation of the kinetic contact of tires rolling on the rough,
rigid-pavement [17].
After analyzing the aforementioned literature, we found that research on skid resistance primarily
focuses on the macro or micro-texture of the pavement, by which the anti-skid property could be
achieved. In addition, there are two methods to model asphalt pavement in the finite element analysis.
One approach is modeling the pavement as a flat rigid surface, while the other one is an analytical
rigid body with a macro-texture surface. It is apparent that both means of modeling consider the
asphalt pavement as a rigid body, disregarding its elasticity.
In the field of terrain vehicle mechanics, the fundamental source of vehicle braking is the friction
between the tires and pavement. As illustrated in Figure 1a, the pedal force F
p
is delivered to the
wheel brake the moment the driver steps on the pedal, forming the frictional moment T
µ
opposite
the momentum of the tire. This moment could be regarded as the circumferential component F
µ
,
which is applied to the tire-pavement contact region to prohibit the rotation of the tire. Simultaneously,
the pavement generates a reactive force on the vehicle, namely, the ground braking force F
b
, which
ultimately slows down vehicles or even allows them come to a complete halt. In other words, F
b
is
equal to F
µ
, which is also comparable to T
µ
divided by the tire radius r. Nevertheless, restrained by
the upper limit of the adhesive force F
φ
(the maximum braking force F
bmax
is equal to F
φ
), F
b
will
not rise as soon as it runs up to F
φ
(Figure 1b). Furthermore, from the aspect of tribology, it can be
concluded that physical properties of the interface, such as variations in material stiffness, will result
in the change in contact area, which will then have an influence on the frictional force (Chengtao Wang
2002 [
18
]). Eventually, the actual tire-pavement area will vary as a result of pavement characteristics
such as the diversification of recoverable resilient. Accordingly, the force of adhesion F
φ
will also
change, accounting for differentiation in the tire-oriented pavement braking function (Jide Zhuang
1986 [19], Liangxi Wang 2008 [20]).
Data produced from the uniaxial compressive strength testing of pavement with normally
structured the asphalt specimens is generally above 1000 MPa (You et al. 2009 [
21
]; Goh et al. 2011 [
22
]);
a value seemingly much higher than the longitudinal tire stiffness. Therefore, in consideration of
time expended in a simulated calculation, the deformation of asphalt pavements is usually ignored
in modeling (Srirangam 2013 [
13
], Hao Wang 2014 [
23
]). In other words, the pavement is defined
as a rigid body in simulations. Nonetheless, along with the diversification of paving materials,
the elastic modulus of asphalt mixtures also varies significantly. For instance, dry process crumb
rubber modified (CRM) asphalt mixtures, which plays an indispensable role in noise reduction and
the de-icing (Chunxiu Zhou 2006 [
24
], Xudong Wang 2008 [
25
]), is characterized by its remarkable
elasticity. In addition, a high content of crumb rubber, which is added to asphalt mixtures, usually
Appl. Sci. 2017,7, 1123 3 of 16
reduces the mixture modulus to half of that of the original (Lili Yao 2012 [
26
]). Such elasticity has
the capacity to facilitate the resilience of CRM asphalt mixtures, which are characterized by a large
elastic deformation under external loading conditions and a dramatic return to its original shape
immediately after the removal of the load in comparison to that of ordinary asphalt mixtures (Miao Yu,
Guoxiong Wu 2014 [
27
29
]). In view of the distinctly narrowed gap of moduli between tires and
resilient pavements such as CRM asphalt pavement, the precision of the simulation will inevitably
decrease if the resilient pavement still needs to be modeled as a rigid body. Furthermore, according to
past literature, the actual stiffness of asphalt pavement is not used in tire-pavement coupled modeling,
meaning that the impact of pavement stiffness on tire-pavement friction has not been examined yet
(Hao Wang 2014 [23], Reginald B. Kogbara [30], Shahriar Najafi [31]).
Appl. Sci. 2017, 7, 1123 2 of 16
mechanism of wet-pavement skid resistance and the subsequent effects of tire slip velocity on rigid
pavement under different degrees of wetness were examined.
The second factor is the frictional property of tire rubber. The friction between tire and pavement
is mainly determined by adhesive and hysteretic friction. Hysteric friction is enhanced with rise in
temperature. For this analysis, K.A. Grosch 2001 [11] chose to use the rubber friction model based
upon the tire rubber’s viscoelasticity. Coupling thermos-mechanics with the finite element method,
Srirangam and Anupam 2013 [12,13] estimated the variations in hysteretic friction during tire-
pavement contact due to differences in temperature. This estimation was calculated by simulating a
tire rolling on rigid pavement in CAPA-3D (developed and dated by the group of Mechanics of
Infrastructure Materials at Delft University of Technology, The Netherlands) Finite Element system.
The third final component in exploring the anti-skid properties of pavement is the surface
texture of the pavement. Both the macro-texture and micro-texture are typically used to represent the
skid resistance of pavement. The correlation between pavement texture and skid resisting ability are
often evaluated via various test methods (Forster, S. W. 1990, Burak Sengoz 2014, Malal Kane 2015
[1416]). For instance, Srirangam and Anupam 2013 [12,13] captured morphological data reflecting
the surface of asphalt pavement through X-ray tomography. Furthermore, they reconstructed the
texture of the pavement in CAPA-3D and analyzed their simulation of the kinetic contact of tires
rolling on the rough, rigid-pavement [17].
After analyzing the aforementioned literature, we found that research on skid resistance
primarily focuses on the macro or micro-texture of the pavement, by which the anti-skid property
could be achieved. In addition, there are two methods to model asphalt pavement in the finite
element analysis. One approach is modeling the pavement as a flat rigid surface, while the other one
is an analytical rigid body with a macro-texture surface. It is apparent that both means of modeling
consider the asphalt pavement as a rigid body, disregarding its elasticity.
In the field of terrain vehicle mechanics, the fundamental source of vehicle braking is the friction
between the tires and pavement. As illustrated in Figure 1a, the pedal force Fp is delivered to the
wheel brake the moment the driver steps on the pedal, forming the frictional moment Tμ opposite the
momentum of the tire. This moment could be regarded as the circumferential component Fμ, which
is applied to the tire-pavement contact region to prohibit the rotation of the tire. Simultaneously, the
pavement generates a reactive force on the vehicle, namely, the ground braking force Fb, which
ultimately slows down vehicles or even allows them come to a complete halt. In other words, Fb is
equal to Fμ, which is also comparable to Tμ divided by the tire radius r. Nevertheless, restrained by
the upper limit of the adhesive force Fφ (the maximum braking force Fbmax is equal to Fφ), Fb will not
rise as soon as it runs up to F
φ (Figure 1b). Furthermore, from the aspect of tribology, it can be
concluded that physical properties of the interface, such as variations in material stiffness, will result
in the change in contact area, which will then have an influence on the frictional force (Chengtao
Wang 2002 [18]). Eventually, the actual tire-pavement area will vary as a result of pavement
characteristics such as the diversification of recoverable resilient. Accordingly, the force of adhesion
Fφ will also change, accounting for differentiation in the tire-oriented pavement braking function (Jide
Zhuang 1986 [19], Liangxi Wang 2008 [20]).
(a) (b)
Figure 1. Principles of braking force. (a) Principles of braking force. (b) Relationship of Fμ, Fb and Fφ
during braking.
Figure 1.
Principles of braking force. (
a
) Principles of braking force; (
b
) Relationship of F
µ
,F
b
and F
φ
during braking.
Based on the above background research, the primary objective of this paper is to evaluate the
effect of different asphalt pavements of variable resilience on braking performance on pavement. This
goal was initially achieved using a 3-D finite tire-asphalt pavement interaction model. By adjusting
parameters such as tire pressure and the elastic modulus, behaviors of the dynamic tire-pavement
contraction were studied by discussing the varying features of tire-pavement contact such as tread
deformation in the tangential interface, actual contact area between the tire and the pavement surface
course, and the braking force supplied by the pavement to the tires.
2. Establishment of Tire-Pavement Frictional Contact Simulation Model
To begin, the traffic load and vehicle braking were simulated by establishing 3D tire models.
Next, a road model was built by adopting the pavement structure of “asphalt surface layers + cement
stabilized macadam base + lime-ash cushion + subgrade.” Meanwhile, frictional contact laws were
defined in ABAQUS (a commercial program of Finite Element Analysis, produced by Dassault
Systèmes
®
Johnston, RI, USA, founded in 1978) , and subsequently, the contrastive analysis of kinetic
friction between the tire and the flexible pavement surface was conducted on specimens created with
various combinations of paving material parameters.
The simulation model of the dynamic friction due to tire-pavement contact was created in a
three-step process shown in Figure 2. Specifically, a 3D model was built, then the steady state of the
kinetic contact was analyzed in ABAQUS/Standard solver based upon static contact.
Appl. Sci. 2017,7, 1123 4 of 16
Appl. Sci. 2017, 7, 1123 4 of 16
Figure 2. 3D Tire-road contact modeling steps in ABAQUS.
2.1. Establishment of 3D Model for Grooving Radial Tires
Referring toSteady-state rolling analysis of a tire’ of ABAQUS 6.10 Example Problem Manual
[32], three steps were used to create the 3D models of grooving radial tires: (1) simplification before
modeling, (2) importing a 2D tire cross-sectional model into ABAQUS, and (3) 3D model generation
of pneumatic tires:
(1) Simplification before Modeling. In order to improve the computational efficiency, the total
cross section of a 2D model was drawn using CAD2014 software(developed by Autodesk corporation
in San Rafael, CA, USA., founded in 1982), which was simplified according to the following:
1 Reduce the poor shape of the cross-sectional element;
2 Simplify the contact constraint between the bead chafer and the wheel hub (see Figure 3 for
details. Next, simplify the wheel hub as a rigid constraint element, which shares a node with the
tire bead);
3 Use the rebar elements to simulate the tire’s steel cord and inner liners.
Figure 3. Simplification of contact conditions between tire bead and wheel hub.
Assembly and inflation
Establishment of 2D tire model
Rotation of symmetry model and
results transfe
r
Generation of 3D tire model 3D road modeling
Tire-road static contact
Steady-state rolling
Confirmation of material
parameters
Selection of pavement structure
Tire
modeling
Dynamic friction
contact analysis
Road
modelin
g
Hub
Figure 2. 3D Tire-road contact modeling steps in ABAQUS.
2.1. Establishment of 3D Model for Grooving Radial Tires
Referring to ‘Steady-state rolling analysis of a tire’ of ABAQUS 6.10 Example Problem Manual [
32
],
three steps were used to create the 3D models of grooving radial tires: (1) simplification before
modeling; (2) importing a 2D tire cross-sectional model into ABAQUS; and (3) 3D model generation of
pneumatic tires:
(1) Simplification before Modeling. In order to improve the computational efficiency, the total
cross section of a 2D model was drawn using CAD2014 software (developed by Autodesk corporation
in San Rafael, CA, USA, founded in 1982), which was simplified according to the following:
1. Reduce the poor shape of the cross-sectional element;
2.
Simplify the contact constraint between the bead chafer and the wheel hub (see Figure 3for
details. Next, simplify the wheel hub as a rigid constraint element, which shares a node with the
tire bead);
3. Use the rebar elements to simulate the tire’s steel cord and inner liners.
Appl. Sci. 2017, 7, 1123 4 of 16
Figure 2. 3D Tire-road contact modeling steps in ABAQUS.
2.1. Establishment of 3D Model for Grooving Radial Tires
Referring toSteady-state rolling analysis of a tire’ of ABAQUS 6.10 Example Problem Manual
[32], three steps were used to create the 3D models of grooving radial tires: (1) simplification before
modeling, (2) importing a 2D tire cross-sectional model into ABAQUS, and (3) 3D model generation
of pneumatic tires:
(1) Simplification before Modeling. In order to improve the computational efficiency, the total
cross section of a 2D model was drawn using CAD2014 software(developed by Autodesk corporation
in San Rafael, CA, USA., founded in 1982), which was simplified according to the following:
1 Reduce the poor shape of the cross-sectional element;
2 Simplify the contact constraint between the bead chafer and the wheel hub (see Figure 3 for
details. Next, simplify the wheel hub as a rigid constraint element, which shares a node with the
tire bead);
3 Use the rebar elements to simulate the tire’s steel cord and inner liners.
Figure 3. Simplification of contact conditions between tire bead and wheel hub.
Assembly and inflation
Establishment of 2D tire model
Rotation of symmetry model and
results transfe
r
Generation of 3D tire model 3D road modeling
Tire-road static contact
Steady-state rolling
Confirmation of material
parameters
Selection of pavement structure
Tire
modeling
Dynamic friction
contact analysis
Road
modelin
g
Hub
Figure 3. Simplification of contact conditions between tire bead and wheel hub.
Appl. Sci. 2017,7, 1123 5 of 16
(2) Importing a 2D Tire Cross-sectional Model into ABAQUS. To start, the simplifed 2D tire
cross-sectional model was imported into ABAQUS. Subsequently, the steel cord of the tire and inner
liners were defined as the primary tire materials.
1 Rubber materials
This study aims to establish a 3D model for a 175SR14 groove tire. The Neo-Hooken model
was selected to describe the constitutive relationship of the super elasticity (Yanfeng Zhu 2006 [
33
],
Yongguan Wang 2007 [
34
]). A Prony series is adopted to define the viscoelasticity of the rubber
in ABAQUS. Both the above parameters were calibrated to acquire deflection values close to
experimental measurements. Please see Table 1for the relative tire rubber parameters (the simulated
and tested datum).
Table 1. Tire rubber material parameters.
Material
Parameters
Neo-Hooken Model Parameters
in ABAQUS
Tensile
Modulus/MPa
Tensile
Strength/MPa
Elongation
Ratio/%
Permanent
Deformation/%
C10 (kPa) C01 (kPa) D1(kPa) M100 M300 Tb Eb Ps
Tread 835 0 0 2.5 9.9 19.1 544 15
Sidewall 1000 0 0 2.3 9.3 15.1 450 10
Note: In this table, M100 and M300, respectively, represent the tension the specimens bear under a 100% and 300%
tensile ratio per unit area.
2 Steel cord-rubber composite materials
Steel cord-rubber composite materials are usually composed of cords in different orientations.
The nonlinearity of rubber results in anisotropy and nonlinearity of the steel cord-rubber composite
material in tires. Therefore, a rebar layer was applied to simulate the composite materials layer. First,
the steel cord and inner liner were defined in ABAQUS and secondly, the membrane element that
represents the steel cord in the defined steel cord layer was embedded. Meanwhile, the membrane
element representing the inner liner in the inner rubber layer was also embedded to accomplish the
simulation of the steel cord and inner liner. The parameters of the steel cord (Belt-1, Belt-2) and inner
liner (Carcass) were defined successively (see Table 2).
Table 2. Description of material properties used in the model development.
Tire Section Young’s
Modulus (GPa)
Poisson’s
Ratio ()
Density
(g/cm3)
Area per
Bar (mm2)
Spacing
(mm)
Orientation
Angle ()
Tread From Lab test 0.45 1.12 - - -
Sidewall 1.15
Belt-1 172.2 0.3 5900 0.212 1.16 70
Belt-2 110
Carcass 9.9 0.3 1500 0.421 1.00 0
(3) 3D model generation of pneumatic tires.
Definitions the section unit type, mesh partition, and 2D tire inflation (tire pressure of 250 kPa)
were accomplished in this phase. Furthermore, the 2D tire section was used to generate a 3D tire
model. Therefore, The final step in tire modeling was to transform the 2D section property into a 3D
tire model.
Appl. Sci. 2017,7, 1123 6 of 16
2.2. Pavement Structure Modeling
2.2.1. Pavement Structure Setting
The road asphalt pavement structure was adopted as 4 cm + 6 cm + 8 cm, as illustrated in Table 3,
which is commonly used in China’s major highways. The thickness of the base and the bed course
was 18 and 31 cm respectively. A displacement restriction is imposed on both longitudinal ends in
the xdirection and transverse ends in the ydirection of the pavement; the consolidation constraint
was applied to the bottom surface separately. Moreover, the entirety of the 3D pavement model was
divided according to the principle that meshing density should be cut from the region of tire-pavement
contact to the boundaries in every direction.
2.2.2. Design of Road Pavement Materials
In attempt to ameliorate the enhance of asphalt pavement, several authors found that adding
crumb rubber into the asphalt mixture by dry process can improve the overall elastic deformation
capacity, thus increasing the tire grip (Xudong Wang 2008 [
25
]) and strengthening braking performance
of the pavement (Chengtao Wang 2002 [
18
], Jide Zhuang 1986 [
19
], Liangxi Wang 2008 [
20
]). Therefore,
based on the research findings of Miao Yu and Guoxiong Wu 2014 [
27
29
], the asphalt specimens
with 0%, 4% and 5.5% crumb rubber content were fabricated (below, the corresponding pavements
are functionally named as low-E, med-E, and high-E in sequence). The crumb rubber content herein
represents the percentage of crumb rubber volume accounts for total aggregate volume of asphalt
specimens. Furthermore, the volumetric parameters were measured for the purpose of comparison
between the effects of different pavement properties on tire brake performance. Table 3outlines the
pavement structure and relevant material parameters. Besides, data of elasticity modulus in this table
represents uniaxial compressive modulus of resilience, originating from uniaxial compression test at
20 C.
Table 3. Parameters of pavement structure modeling.
Pavement Structure Layer Thickness (cm) Elasticity Modulus (MPa) Poisson’s Ratio Density (g/cm3)
Surface course 4
1480 (without crumb rubber, low-E) 0.35 2.474
1265 (with 4% crumb rubber, med-E) 0.40 2.420
886 (with 5.5% crumb rubber, high-E) 0.40 2.387
Leveling course 6 1100 0.35 2.432
Asphalt base course 8 1000 0.35 2.471
Cement-stabilized
Macadam Base Course 18 1500 0.25 2.056
Lime-fly ash Soil
Cushion 31 750 0.25 1.924
Subgrade 500 35 0.35 1.918
Note: In this paper, low-E, med-E and high-E respectively represent the elasticity of pavement with 0%, 4% and
5.5% crumb rubber.
2.3. Tire-Flexible Pavement Frictional Contact Simulation
2.3.1. Definition of the Tire-Pavement Frictional Contact in ABAQUS
The following parameters facilitating frictional contact and the subsequent tire-pavement
interaction analysis (Y Liu et al. 2015 [35]) were defined.
1
Slip ratio σx(Equation (1)) is a representation of the slip status during the tire rolling phase,
σx=
uare f f ·ωw
ua
×100% (1)
where
Appl. Sci. 2017,7, 1123 7 of 16
ωw—the rotational angular velocity of the wheel hub; rad/s
reff—the effective radius of the wheel; m
ua—the actual longitudinal velocity of the tire; m/s
2
The static friction coefficient
µ
(Equation (2)) is defined as the friction between the tire and
pavement in the initial contact phase (the tire is about to slide), in which the tire velocity is zero
µ=F/N(2)
where
F—the tangential force between tire and pavement contact
N—the normal force, perpendicular to the contact between tire and pavement
3
The braking force coefficient
φb
(Equation (3)) describes the braking ability of asphalt
pavements. In addition,
φb
is the Skid Number (SN), representing tires-pavement contact when
braking; a larger φbwill account for a higher braking efficiency of the tires.
φb= 100 ×Fx/Fz(3)
where
Fx—the horizontal braking force of the pavement against the tire at the contact region
Fz—the upper load borne by the tires
4
In order to facilitate comparative analysis, the actual longitudinal velocity of the center of the
tire was set at 80 km/h, and the static friction coefficient
µ
was 0.7 (Jide Zhuang 1986 [
19
], Judge, A. W.
2008 [36]).
5
Tire-asphalt pavement contact definition
Static contact between the tire and asphalt pavement could be modeled via two methods;
displacement control and load control. In comparison to the latter, the former usually decreases
calculation time and in comparison, produces more reliable results. Thus, the displacement control of
the tire and pavement contact was established by applying 2 cm displacement on the rigid reference
node of the tire. Secondly, the load control of the tire and pavement contact was set up, that is, causing
us to remove the pre-assigned displacement and apply vertical displacement on the tire reference
node with respect to the pavement. The tire-pavement static contact was determined via the two steps
above. Furthermore, the tire-pavement contact was set at “hard contact” of “finite sliding”. Meanwhile,
the method of combining isotropic Coulomb friction combined with the penalty function algorithm
was adopted to realize the tire-pavement frictional contact simulation model in Figure 4a.
2.3.2. Validation of the 3D Model of Pneumatic Tire-Asphalt Pavement Contact
The complicated nonlinear characteristic of the kinetic contact between tire and pavement will
have a major effect not only on the convergence of both the implicit and explicit analyses, but also on
the accuracy and computation time of the above analyses. Therefore, before carrying out the dynamic
analysis of the tire-pavement contact, it is necessary to successively validate the simulation of the
pneumatic tire and its static contact with the pavement.
1
Tire inflation
Figure 4b shows the Mises equivalent stress nephogram of the 2D tire cross section. It can be
seen that the steel cord bears the primary load of the inner tire after inflation. While the whole tire is
under tension, the maximum stress lies in the middle of the steel cord found in the tread. To facilitate
investigation of the stress-strain characteristics found in the tire rubber materials, the inner liner of the
tire was removed.
Appl. Sci. 2017,7, 1123 8 of 16
Appl. Sci. 2017, 7, 1123 8 of 16
(a)
(b)
(c)
(d)
(e)
Figure 4. Cont.
Appl. Sci. 2017,7, 1123 9 of 16
Figure 4.
Stress and strain nephogram of the 3D model of pneumatic tire-asphalt pavement contact.
(
a
) 3D Tire-pavement contact model; (
b
) Mises equivalent stress nephogram of the inflated tire; (
c
) Mises
equivalent stress nephogram of the inflated tire rubber materials; (
d
) Deformation nephogram of the
inflated tire rubber materials; (
e
) Deformation nephogram of the inflated tire; (
f
) Pressure distribution
of tire tread on the contact region; (
g
) Pressure distribution of Pavement surface on the contact region.
It can be observed in Figure 4c,d that both the maximum values of the Mises stress and the total
strain appeared near the hub constraints when assembled with a wheel hub and bearing inflation
pressure. In contrast, when the steel cord bore the maximum tensile stress, the tread rubber presented
relatively smaller stress without the self-weight load. As depicted in Figure 4d, it was found that
the consolidation constraints contributed to zero displacement around the wheel hub, whereas the
aligned regions showed higher stress. In addition, the tread showed lower Mises stress, accounting for
a larger deformation of the rubber materials near the wheel hub of the sidewall. Figure 4e depicts the
deformation nephogram of the inflated tire along its tread and sidewall directions. It is noted that the
deformation in 1 orientation (U1) was primarily created in the connecting region of the sidewall and
shoulder. On the other hand, the deformation in 2 directions (U2) was always concentrated on the
sidewall near the hub. It can be concluded that, from the above analysis of Figure 4c–e, the principle
deformation region lied in the sidewall of tires, in accordance with practical conditions.
2
Static tire contact conditions
Under the tire-pavement contact conditions shown in Figure 4f,g, tire grooves accounted for the
concentration of the tire-pavement ground pressure, which lied mainly within the longitudinal pattern
rather than out of the grooves. Accordingly, the contact pressure on the pavement surface was also
gathered in the middle of the contact region.
A photograph of the tire’s static loaded test performed by UTTM Stiffness Tester (Testing Service
GmbH, Aachen, North Rhine-Westphalia, Germany), is presented in Figure 5a. Comparison of the
test data of load-tire vertical deformation, size of contact region as well as the actual contact area with
the relative numerically predicted results are shown in Figure 5b and Table 4. It can be seen that the
predicted results seem very close to the results of the lab experiments.
Table 4.
Contact area comparison of the numerically simulated results and experiment measurements.
Tire
Pressure
(kPa)
Applied
Load (N)
Experimentally Measured Data Numerically Simulated Results
Length (L)
(mm)
Width (W)
(mm)
Area
(cm2)
Length (L)
(mm)
Width (W)
(mm)
Area
(cm2)
200 2200 125.0 102.5 104.0 119.3 99.7 98.5
220 3200 147.6 106.1 135.0 142.1 103.6 128.6
Note: Land Wis the relative maximum value of the length and width in the contact zone.
Appl. Sci. 2017,7, 1123 10 of 16
Appl. Sci. 2017, 7, 1123 9 of 16
(f)
(g)
Figure 4. Stress and strain nephogram of the 3D model of pneumatic tire-asphalt pavement contact.
(a) 3D Tire-pavement contact model, (b) Mises equivalent stress nephogram of the inflated tire, (c)
Mises equivalent stress nephogram of the inflated tire rubber materials, (d) Deformation nephogram
of the inflated tire rubber materials, (e) Deformation nephogram of the inflated tire, (f) Pressure
distribution of tire tread on the contact region, (g) Pressure distribution of Pavement surface on the
contact region.
Static tire contact conditions
Under the tire-pavement contact conditions shown in Figure 4f,g, tire grooves accounted for the
concentration of the tire-pavement ground pressure, which lied mainly within the longitudinal
pattern rather than out of the grooves. Accordingly, the contact pressure on the pavement surface
was also gathered in the middle of the contact region.
A photograph of the tire’s static loaded test performed by UTTM Stiffness Tester (Testing Service
GmbH, Aachen, North Rhine-Westphalia, Germany), is presented in Figure 5a. Comparison of the
test data of load-tire vertical deformation, size of contact region as well as the actual contact area with
the relative numerically predicted results are shown in Figure 5b and Table 4. It can be seen that the
predicted results seem very close to the results of the lab experiments.
(a) (b)
Figure 5. Verification of simulation model against experimental data on tire static test. (a) Tire static
loaded test. (b) Load-tire vertical deformation comparison of numerically simulated results and
experiment measurements.
Table 4. Contact area comparison of the numerically simulated results and experiment measurements.
Tire Pressure
(kPa)
Applied Load
(N)
Experimentally Measured Data Numerically Simulated Results
Length (L)
(mm)
Width (W)
(mm)
Area
(cm
2
)
Length (L)
(mm)
Width (W)
(mm)
Area
(cm
2
)
200 2200 125.0 102.5 104.0 119.3 99.7 98.5
220 3200 147.6 106.1 135.0 142.1 103.6 128.6
Note: L and W is the relative maximum value of the length and width in the contact zone.
Figure 5.
Verification of simulation model against experimental data on tire static test. (
a
) Tire
static loaded test; (
b
) Load-tire vertical deformation comparison of numerically simulated results and
experiment measurements.
3. Simulation Analysis of Tire-Asphalt Pavement Frictional Contact
3.1. Simulation Conditions Design of the Tire-Asphalt Pavement Frictional Contact
It is well known that the braking force (coefficient) changes with variations in slip ratio. At the
early stage of the tire braking procedure, the adhesive force, F
φ
, is proportional to the slip ratio.
However, because the pavement braking force, F
b
, is restrained by the adhesive force, F
φ
,F
b
will stop
rising upon reaching the maximum F
φ
value, and the slip ratio will continue to increase. Therefore, it is
relevant to note that if pavement could provide tires with a greater adhesive force, F
φ
, tires will receive
a greater braking force, F
b
, from the pavement, facilitating the vehicle braking efficiency. Thus, this
study analyzes elasticity’s contribute to tire braking efficiency on pavement using various slip ratios.
The three slip ratios listed in Table 5were used to analyze the frictional contact of tire-pavement.
Table 5. Conditions of brake efficiency in different slip ratios.
Pavement Types Slip Ratio (%)
7 10 14
low-E low-SR med-SR high-SR
med-E low-SR med-SR high-SR
high-E low-SR med-SR high-SR
Note: In this table, E represents pavement Elasticity with or without crumb rubber addition, namely, in accordance
with the pavement type in Table 3. Besides, SR is the abbreviation of Slip Ratio.
3.2. Tread Deformation
Tire braking behavior has a distinct impact on tangential tire deformation. Therefore,
the tangential deformation was examined to investigate tire-pavement frictional behaviors.
Figure 6depicts tangential deformation of the tire tread along vehicle’s direction of motion. It can
be inferred from the nephogram that:
When the slip ratio is only 7%, the tread’s tangential deformation is insignificant. Nevertheless,
as the pavement’s elasticity is improved, the deformed area has become longer and wider, extending to
the marginal region of sidewall in the direction of the tire’s motion. These phenomena account for the
enlargement of the tire-pavement contact area; the effect tire adhesion on highly elastic pavement is a
superior braking agent in comparison to that of common pavement with no crumbed rubber additives.
Appl. Sci. 2017,7, 1123 11 of 16
Secondly, under each of the nine conditions, the direction of tread deformation is opposite to the
tire’s motion path. Under conditions of high-E, the tread deformation area is significantly larger in
comparison to conditions of low-E and med-E. This pattern is also found in the slip direction of the tire
head’s mesh. The above findings explain that while stiffness decreased and elasticity improvements
were made in the paving materials, the deformity and braking force applied to the tires increases.
Therefore, the tire-pavement contact area enlarges with elasticity. This trend indicates that appropriate
decreases in pavement stiffness could facilitate enough tire-pavement contact to enhance tire adhesion,
improving brake efficiency.
By examining the tread deformation along the direction of tire movement under 10% and 14% slip
ratio, we see that when the slip ratio is 14%, the tread deformation slightly decreases, indicating that
tire adhesion does not always improve with the increased slip ratio. This change agree with the law
that as the slip ratio is between 10% and 15%, the tire braking force coefficient will reach the maximum
value [18].
Appl. Sci. 2017, 7, 1123 11 of 16
Figure 6. Tangential deformation nephogram of tire tread under different slip ratios.
3.3. Pavement Braking Effect
Tire slip ratio is directly correlated to the tangential deformation found in the tire-pavement
contact zone. Therefore, the tangential displacement of the pavement surface, along the direction of
tire movement (Figure 7), is primarily used to investigate pavement deformation under various slip
ratios. Figure 8 illustrates the pavement’s tangential deformation response under three types of tire
slip ratios. The comparison shows that pavement tangential deformation varies most significantly
with the alternation of slip ratios. For example, consider a 7% slip ratio; the tangential deformation is
generally no more than 0.1mm, whereas the deformation could reach 1mm as the slip ratio reaches
10% or higher. The figure also depicts the impact of pavement modulus on tangential interaction,
which should not be ignored. It can be observed that in highly elastic pavement (high-E), the
tangential resistance to tire rolling is more significant than that of other pavements (low-E and med-
E) under the same slip ratio. Therefore, it can be concluded that changes in tire-pavement tangential
behavior caused by slight alterations in pavement resilience can be neglected due to their negligibility
in comparison to slip ratio.
med-E and low-SR med-E and med- SR med-E and high- SR
low-E and low-SR low-E and med- SR low-E and high- SR
high-E and low-SR high-E and med- SR high-E and high- SR
Figure 6. Tangential deformation nephogram of tire tread under different slip ratios.
Appl. Sci. 2017,7, 1123 12 of 16
3.3. Pavement Braking Effect
Tire slip ratio is directly correlated to the tangential deformation found in the tire-pavement
contact zone. Therefore, the tangential displacement of the pavement surface, along the direction of
tire movement (Figure 7), is primarily used to investigate pavement deformation under various slip
ratios. Figure 8illustrates the pavement’s tangential deformation response under three types of tire slip
ratios. The comparison shows that pavement tangential deformation varies most significantly with the
alternation of slip ratios. For example, consider a 7% slip ratio; the tangential deformation is generally
no more than 0.1mm, whereas the deformation could reach 1mm as the slip ratio reaches 10% or higher.
The figure also depicts the impact of pavement modulus on tangential interaction, which should not
be ignored. It can be observed that in highly elastic pavement (high-E), the tangential resistance to tire
rolling is more significant than that of other pavements (low-E and med-E) under the same slip ratio.
Therefore, it can be concluded that changes in tire-pavement tangential behavior caused by slight
alterations in pavement resilience can be neglected due to their negligibility in comparison to slip ratio.
Appl. Sci. 2017, 7, 1123 12 of 16
Figure 7. Vertical route of the tire movement.
Figure 8. Tangential deformation of pavement surface layer under different slip ratios of tires.
Figures 9 and 10 respectively present the correlation of contact area and pavement braking force
under different slip ratios. As the slip ratio increases from 7 to 10%, the contact area enlarged,
intensifying the tire-pavement friction, causing an upward trend in the braking force applied by the
pavement. When the slip ratio raised from 10 to 14%, the contact area began to reduce, accounting
for degradation of the tire adhesion effect. According to Figure 6d, the braking force also declined
along with increasing slip ratio. The two figures illustrate that tire-pavement contact area is related
to pavement braking force. In other words, tire adhesion has a substantial impact on the braking force
applied by asphalt pavements.
Figure 7. Vertical route of the tire movement.
Appl. Sci. 2017, 7, 1123 12 of 16
Figure 7. Vertical route of the tire movement.
Figure 8. Tangential deformation of pavement surface layer under different slip ratios of tires.
Figures 9 and 10 respectively present the correlation of contact area and pavement braking force
under different slip ratios. As the slip ratio increases from 7 to 10%, the contact area enlarged,
intensifying the tire-pavement friction, causing an upward trend in the braking force applied by the
pavement. When the slip ratio raised from 10 to 14%, the contact area began to reduce, accounting
for degradation of the tire adhesion effect. According to Figure 6d, the braking force also declined
along with increasing slip ratio. The two figures illustrate that tire-pavement contact area is related
to pavement braking force. In other words, tire adhesion has a substantial impact on the braking force
applied by asphalt pavements.
Figure 8. Tangential deformation of pavement surface layer under different slip ratios of tires.
Appl. Sci. 2017,7, 1123 13 of 16
Figures 9and 10 respectively present the correlation of contact area and pavement braking
force under different slip ratios. As the slip ratio increases from 7 to 10%, the contact area enlarged,
intensifying the tire-pavement friction, causing an upward trend in the braking force applied by the
pavement. When the slip ratio raised from 10 to 14%, the contact area began to reduce, accounting
for degradation of the tire adhesion effect. According to Figure 6, the braking force also declined
along with increasing slip ratio. The two figures illustrate that tire-pavement contact area is related to
pavement braking force. In other words, tire adhesion has a substantial impact on the braking force
applied by asphalt pavements.
Appl. Sci. 2017, 7, 1123 13 of 16
Figure 9. Tire-pavement contact area under different slip ratios.
Figure 10. Braking force of pavement under different slip ratios.
Figure 11 also shows that the braking force coefficient of pavement does not always enlarge with
increases in slip ratio; this coefficient will decrease after reaching its peak value. Using the tire
modeled in this research, it was found that pavement type has the most significant braking impact at
a slip ratio value near 10%. Furthermore, with reduction in contact area, the effect of pavement type
on braking diminished with slip ratios greater than 10%. However, it can be observed that for the
most elastic pavement (high-E), the corresponding braking force coefficient is greater than the other
two types of less elastic pavement. As the slip ratio was further improved, the braking effect of the
high elastic pavement began to degrade, nonetheless, this pavement’s braking effect is superior to
that of the other pavements. Therefore, it can be concluded that the enhancement of pavement
elasticity will give rise to the braking efficiency of the tires under different slip ratios.
Figure 11. Pavement braking force coefficient under different slip ratios.
Figure 9. Tire-pavement contact area under different slip ratios.
Appl. Sci. 2017, 7, 1123 13 of 16
Figure 9. Tire-pavement contact area under different slip ratios.
Figure 10. Braking force of pavement under different slip ratios.
Figure 11 also shows that the braking force coefficient of pavement does not always enlarge with
increases in slip ratio; this coefficient will decrease after reaching its peak value. Using the tire
modeled in this research, it was found that pavement type has the most significant braking impact at
a slip ratio value near 10%. Furthermore, with reduction in contact area, the effect of pavement type
on braking diminished with slip ratios greater than 10%. However, it can be observed that for the
most elastic pavement (high-E), the corresponding braking force coefficient is greater than the other
two types of less elastic pavement. As the slip ratio was further improved, the braking effect of the
high elastic pavement began to degrade, nonetheless, this pavement’s braking effect is superior to
that of the other pavements. Therefore, it can be concluded that the enhancement of pavement
elasticity will give rise to the braking efficiency of the tires under different slip ratios.
Figure 11. Pavement braking force coefficient under different slip ratios.
Figure 10. Braking force of pavement under different slip ratios.
Figure 11 also shows that the braking force coefficient of pavement does not always enlarge with
increases in slip ratio; this coefficient will decrease after reaching its peak value. Using the tire modeled
in this research, it was found that pavement type has the most significant braking impact at a slip ratio
value near 10%. Furthermore, with reduction in contact area, the effect of pavement type on braking
diminished with slip ratios greater than 10%. However, it can be observed that for the most elastic
pavement (high-E), the corresponding braking force coefficient is greater than the other two types of
less elastic pavement. As the slip ratio was further improved, the braking effect of the high elastic
pavement began to degrade, nonetheless, this pavement’s braking effect is superior to that of the other
pavements. Therefore, it can be concluded that the enhancement of pavement elasticity will give rise
to the braking efficiency of the tires under different slip ratios.
Appl. Sci. 2017,7, 1123 14 of 16
Appl. Sci. 2017, 7, 1123 13 of 16
Figure 9. Tire-pavement contact area under different slip ratios.
Figure 10. Braking force of pavement under different slip ratios.
Figure 11 also shows that the braking force coefficient of pavement does not always enlarge with
increases in slip ratio; this coefficient will decrease after reaching its peak value. Using the tire
modeled in this research, it was found that pavement type has the most significant braking impact at
a slip ratio value near 10%. Furthermore, with reduction in contact area, the effect of pavement type
on braking diminished with slip ratios greater than 10%. However, it can be observed that for the
most elastic pavement (high-E), the corresponding braking force coefficient is greater than the other
two types of less elastic pavement. As the slip ratio was further improved, the braking effect of the
high elastic pavement began to degrade, nonetheless, this pavement’s braking effect is superior to
that of the other pavements. Therefore, it can be concluded that the enhancement of pavement
elasticity will give rise to the braking efficiency of the tires under different slip ratios.
Figure 11. Pavement braking force coefficient under different slip ratios.
Figure 11. Pavement braking force coefficient under different slip ratios.
4. Conclusions and Discussion
To increase brake efficiency and enhance driving safety, the 3D dynamic frictional contact model
was created to conduct a reliable analysis of tire-pavement friction. Through this method, the following
conclusions were determined.
First: increasing pavement elasticity could enlarge the tire-pavement actual contact area, providing
tires with stronger grip.
Second: slip ratio has the most significant impact on frictional behaviors during tire-pavement
contact. However, under the same slip ratio, high elasticity significantly interferes with tire rolling in
comparison to pavements of ordinary elasticity.
Third: the braking force coefficient can be slightly raised by the distinct improvement of pavement
elasticity. However, braking distance is sensitive to tiny variations in this coefficient, allowing
anti-skidding improvements to be made in asphalt by remarkably increasing the pavement’s elasticity.
Pavement skid resistance, coupled with vehicle, tire and pavement surface layer, is a problem
that includes factors such as aggregate hardness, pavement surface texture and stiffening of paving
materials. Moreover, analyzed from the aspect of the tire, this issue also investigated the effect of
tire inflation pressure; tread pattern and the physical and mechanical properties of tread rubber
materials. In addition, investigated from the angle of tire-pavement coupling, it is a systemic problem
that incorporates tire slip ratio, tire-pavement contact behavior, and even the appropriate friction
law. Conventional methods focus upon macro and micro texture effects on the frictional properties
of the tire, to decrease the skid resistance of asphalt pavement. Investigating the changes in skid
resistance caused by altering the recoverable resilient deformation property of pavement is a new
approach to increasing driver safety. This method can be used to facilitate tire grip and enhance
braking performance. This paper investigates pavement skid resistance from the aspect of paving
materials’ moduli; tire-pavement friction coupled with pavement texture, heat transfer by coupled
frictional behaviors, stiffness modulus, and water film effects will be discussed in future research.
Acknowledgments:
This work is financially supported by the 2014 Chongqing Higher Education Institution’s
Excellent Achievements Program (Major Project) (Theme: Warm mix, semi-flexible compound pavement
Technology (KJZH14104)), 2015 Chongqing Higher Education Institution’s scientific and technological research
program (Theme: Research on the skid Resistance Performance of CRM asphalt pavement based on the
tire-pavement kinetic friction test system (KJ1500508)), and the 2016 National Natural Science Foundation of China
(Tire braking-oriented anti-skid mechanism and estimating model of friction coefficient of asphalt pavement,
No. 51608085).
Author Contributions:
Miao Yu was in charge of the whole research program; Guoxiong Wu built the trial
protocol; Lingyun Kong and Yu Tang performed the experiments and data analysis. All authors discussed and
contributed to the preparation and revision of the manuscript.
Conflicts of Interest: The authors declare no conflict of interest.
Appl. Sci. 2017,7, 1123 15 of 16
References
1. Henry, J.J. Evaluation of Pavement Friction Characteristics (A Synthesis of Highway Practice); NCHRP Synthesis
No. 291; National Cooperative Highway Research Program; Transportation Research Board: Washington,
DC, USA, 2000.
2.
Horne, W.B.; Dreher, R.C. Phenomena of Pneumatic Tire Hydroplaning; NASA TN D-2056; National Aeronautics
and Space Administration: Washington, DC, USA, 1963.
3.
Martin, C.S. Hydrodynamics of Tire Hydroplaning; Final Rep. Project B-608; Georgia Institute of Technology:
Atlanta, GA, USA, 1966.
4.
Eshel, A.A. Study of Tires on a Wet Runway; Rep. No. RR67-24; Ampex Corp.: Redwood City, CA, USA, 1967.
5.
Tsakonas, S.; Henry, C.J.; Jacobs, W.R. Hydrodynamics of Aircraft Tire Hydroplaning; NASA CR-1125; National
Aeronautics and Space Administration: Washington, DC, USA, 1968.
6.
Horne, W.B.; Yager, T.J.; Ivey, D.L. Recent Studies to Investigate Effects of Tire Footprint Aspect Ratio on Dynamic
Hydroplaning Speed; Pottinger, M.G., Yager, T.J., Eds.; The Tire Pavement Interface, ASTM STP 929; ASTM:
Philadelphia, PA, USA, 1986; pp. 26–46.
7.
Ong, G.P.; Fwa, T.F. Wet-pavement hydroplaning risk and skid resistance: Modeling. J. Transp. Eng.
2007
,
133, 590–598. [CrossRef]
8.
Fwa, T.F.; Ong, G.P. Wet-pavement hydroplaning risk and skid resistance: Analysis. J. Transp. Eng.
2008
,134,
182–190. [CrossRef]
9.
Ong, G.P.; Fwa, T.F. Modeling skid resistance of commercial trucks on highways. J. Transp. Eng.
2010
,136,
510–517. [CrossRef]
10. Fwa, T.F.; Pasindu, H.R.; Ong, G.P. Critical rut depth for pavement maintenance based on vehicle skidding
and hydroplaning consideration. J. Transp. Eng. 2012,138, 423–429. [CrossRef]
11.
Grosch, K.A. The relation between the friction and viscoelastic properties of rubber. Proc. R. Soc. Lond. Ser. A
1962,274, 21–39. [CrossRef]
12.
Srirangam, S.K.; Anupam, K.; Scarpas, A.; Kösters, A. Influence of tire temperature increase on friction
measurements-I: Laboratory tests and finite element modeling aspects. In Proceedings of the Transportation
Research Board Annual Meeting, Washington, DC, USA, 13–17 January 2013.
13.
Anupam, K.; Srirangam, S.K.; Scarpas, A.; Kasbergen, C. Influence of temperature on the tire-pavement
friction-II: Analyses. In Proceedings of the Transportation Research Board Annual Meeting, Washington, DC,
USA, 13–17 January 2013.
14.
Forster, S.W. Pavement Microtexture and Its Relation to Skid Resistance; 151B164; Transportation Research
Record; Transportation Research Board: Washington, DC, USA, 1990.
15.
Sengoz, B.; Onsori, A.; Topal, A. Effect of aggregate shape on the surface properties of flexible pavement.
KSCE J. Civ. Eng. 2014,18, 1364–1371. [CrossRef]
16.
Kane, M.; Rado, Z.; Timmons, A. Exploring the texture–friction relationship: From texture empirical
decomposition to pavement friction. Int. J. Pavement Eng. 2015,16, 919–928. [CrossRef]
17.
Srirangam, S.K.; Anupam, K.; Scarpas, A.; Kasbergen, C. Development of a thermomechanical tyre–pavement
interaction model. Int. J. Pavement Eng. 2015,16, 721–729. [CrossRef]
18.
Wang, C.T.; Yao, Z.Q.; Chen, M. Vehicle Tribology; Shanghai Jiaotong University Press: Shanghai, China, 2002;
pp. 400–423.
19. Zhuang, J. Vehicle-Terramechanics; China Machine Press: Beijing, China, 1986.
20. Wang, L.X.; Wang, H.Y. Vehicle Dynamics; National Defence Industry Press: Beijing, China, 2008.
21.
You, Z.; Adhikari, S.; Kutay, M.E. Dynamic modulus simulation of the asphalt concrete using the X-ray
computed tomography images. Mater. Struct. 2009,42, 617–630. [CrossRef]
22. Goh, S.W.; You, Z.; Williams, R.C.; Li, X. Preliminary dynamic modulus criteria of HMA for field rutting of
asphalt pavements: Michigan’s experience. J. Transp. Eng. 2011,137, 37–45. [CrossRef]
23.
Wang, H.; Al-Qadi, I.L.; Stanciulescu, I. Effect of surface friction on tire-pavement contact stress during
vehicle maneuvering. J. Eng. Mech. 2014,140, 04014001. [CrossRef]
24.
Zhou, C. Study on Application Technology of Rubber Particle Asphalt Mixture in Ice and Snow Region.
Ph.D. Thesis, Harbin University of Industry, Harbin, China, 2006.
25.
Wang, X. The Apply Technology of the Crumb Rubber in the Asphalt and Mixture; China Communications Press:
Beijing, China, 2008; pp. 167–197.
Appl. Sci. 2017,7, 1123 16 of 16
26.
Yao, L. Research on Key Technology of Granulated Crumb Rubber Anti-ice Asphalt Pavement. Ph.D. Thesis,
Chang’an Universtity, Xi’an, China, 2012.
27.
Yu, M.; Wu, G. Research on the mix design of dry process crumb rubber modified asphalt mixture.
J. Build. Mater. 2014,17, 100–105.
28.
Yu, M.; Wu, G.; Zhou, J.; Easa, S. Proposed compaction procedure for dry process crumb rubber modified
asphalt mixtures using air void content and expansion ratio. J. Test. Eval. 2014,42, 328–338. [CrossRef]
29.
Yu, M. Study on the Dry Process Crumb Rubber Modified Anti-Skid Layer Based on the Tire-Road Coupling.
Ph.D. Thesis, Chongqing Jiaotong Universtity, Chongqing, China, 2014.
30.
Kogbara, R.B.; Masad, E.A.; Kassem, E.; Scarpas, A.T.; Anupam, K. A state-of-the-art review of parameters
influencing measurement and modeling of skid resistance of asphalt pavements. Constr. Build. Mater.
2017
,
133, 330–339. [CrossRef]
31.
Najafi, S.; Flintsch, G.W.; Medina, A. Linking roadway crashes and tire-pavement friction: A case study.
Int. J. Pavement Eng. 2017,18, 119–127. [CrossRef]
32.
Koishi, M.; Kabe, K.; Shiratori, M. Tire cornering simulation using explicit finite element analysis code.
J. Appl. Polym. Sci. 2000,78, 1566–1572. [CrossRef]
33. Zhu, Y.; Liu, F.; Huang, X.; Li, L. Constitutive model of rubber materials. Rubber Ind. 2006,53, 119–125.
34.
Wang, Y.; Li, X.; Huang, Y. Selection for constitutive model in rubber calculation. The chemical industry and
engineering society of China. In Proceedings of the 4th Seminar China Rubber Products, Zhuzhou, Hunan,
China, 17 November 2007; pp. 443–449.
35.
Liu, Y.; You, Z.P.; Yao, H. An idealized discrete element model for pavement-wheel interaction. J. Mar.
Sci. Technol. 2015,23, 339–343.
36.
Judge, A.W. Automobile engines. In Theory, Design, Construction, Operation, Testing and Maintenance; Hervey
Press: Hervey, Australia, 2008.
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2017 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access
article distributed under the terms and conditions of the Creative Commons Attribution
(CC BY) license (http://creativecommons.org/licenses/by/4.0/).
... With repeated traffic loads, pavement aggregate angles and surface microtextures are repeatedly abraded to present a smoother surface; therefore, the skid resistances of different pavements will exhibit different degrees of attenuation. However, pavement aggregate grain size is a critical factor affecting pavement macrotexture [24][25][26]. Consequently, attention must be paid to the effect of aggregate grain size on pavement skid resistance. To analyse the contact interaction between a tyre and aggregates of different grain sizes in this study, hemispherical shells were used to simulate abraded coarse aggregates, as shown in Figure 3. [24][25][26]. ...
... Consequently, attention must be paid to the effect of aggregate grain size on pavement skid resistance. To analyse the contact interaction between a tyre and aggregates of different grain sizes in this study, hemispherical shells were used to simulate abraded coarse aggregates, as shown in Figure 3. [24][25][26]. Consequently, attention must be paid to the effect of aggregate grain size o ment skid resistance. To analyse the contact interaction between a tyre and aggre different grain sizes in this study, hemispherical shells were used to simulate a coarse aggregates, as shown in Figure 3. ...
... At the same time, the workload and cost of testing for tyre materials are relatively large. Therefore, the mechanical parameters of these materials in Yu et al. [25] are used, as shown in Tables 1 and 2. This study focused on the contact interaction between the rubber tread material and the different grain size aggregates when the tyre is running in the longitudinal direction; ignoring the transverse tyre tread pattern had little effect on the analysis results. Meanwhile, to save computational time, the tyre modelling ignored the transverse tyre tread pattern and retained only the two longitudinal grooves. ...
Article
Full-text available
This study considered the effect of pavement aggregate grain size on tyre–pavement contact interaction during the late stages of pavement skid resistance. First, hemispherical shells 7, 9, and 13 mm in diameter were used to simulate coarse pavement aggregates. Subsequently, a three-dimensional finite element tyre–pavement contact model developed using ABAQUS was employed to analyse the contact interaction between each simplified pavement type and the tyre under steady–state rolling and braking conditions. Finally, the concept of occlusal depth was proposed and applied to characterise pavement skid resistance. The results showed that under steady–state rolling conditions, the peak contact stress of the simplified pavement increased with the pavement mean texture depth, whereas the contact area decreased. Under steady–state braking conditions, the effect of the contact interaction between the tyre and simplified pavement aggregates was ranked in order of superiority as aggregate grain sizes of 9, 7, and 13 mm, indicating that aggregate grain size did not exhibit any correlation with tyre–pavement contact interaction. Additionally, the squares of linear correlation coefficients between the pavement cumulative occlusal depth and horizontal braking force reached 0.921, 0.941, 0.889, and 0.894 for vehicle speeds of 30, 60, 90, and 120 km/h, respectively, indicating that they could be used to assess pavement skid resistance.
... Pavement structure modeling requires the discretization of both surface and bulk, which is more complex if surface roughness is accounted in its actual form and not simplified. Furthermore, asphalt pavement is characterized as well by a viscoelastic rheology and even though it is mostly considered rigid in comparison to the tire, an adequate material constitutive law also for the pavement can be taken into account in pursuit of a more realistic modeling approach [12]. ...
... The sliding response was analyzed through the calculation of a friction coefficient as the ratio between the resultant applied tangential and normal loads. Research performed by [12] focused on the influence of different elastic properties (recoverable resilient deformation) of various pavement structures on the braking performance by setting up a 3D tire-pavement interaction model. They investigated the influence of different system variables such as tread deformation at the contacting interface, actual contact area and the braking force applied within the dynamic friction contact analysis, concluding that pavement elasticity and deformation influence the real contact area. ...
Preprint
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Pavement surface textures obtained by a photogrammetry-based method for data acquisition and analysis are employed to investigate if related roughness descriptors are comparable to the frictional performance evaluated by finite element analysis. Pavement surface profiles are obtained from 3D digital surface models created with Close-Range Orthogonal Photogrammetry. To characterize the roughness features of analyzed profiles, selected texture parameters were calculated from the profile's geometry. The parameters values were compared to the frictional performance obtained by numerical simulations. Contact simulations are performed according to a dedicated finite element scheme where surface roughness is directly embedded into a special class of interface finite elements. Simulations were performed for different case scenarios and the obtained results showed a notable trend between roughness descriptors and friction performance, indicating a promising potential for this numerical method to be consistently employed to predict the frictional properties of actual pavement surface profiles.
... Skid resistance refers to the force that prevents tires from sliding on pavement surfaces by creating an opposing force at the tire-pavement contact area. This aspect is crucial for traffic safety, as it plays a vital role in vehicle control and reduces stopping distances during emergency braking scenarios [1][2][3]. The pavement skid resistance is a multifaceted phenomenon driven by two key components: adhesion and hysteresis. ...
... Based on the analysis, the combined formula derived from the texture and angularity provided the model prediction for SN according to Equation (1): SN = −0.001282t 2 + 0.5594t + 0.0000406a 2 − 0.2491a + 380.9195 (1) where "SN" represents the skid number before polishing, "t" represents the average texture index before polishing, and "a" denotes the average angularity index before polishing. Table 3 presents the actual and predicted SNs based on the provided model. ...
Article
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Skid resistance is a critical aspect for traffic safety since it significantly influences vehicle control and minimizes the distance required for emergency braking. The surface characteristics of pavements play a pivotal role in determining skid resistance. To achieve the optimal skid resistance performance, the pavement must sustain a specific level of friction. Thus, it is advantageous to apply surface treatments in areas that require enhanced friction. This study investigate the impact of factors such as the aggregate source, size, morphological properties, and abrasion levels on the skid resistance and frictional characteristics of a high-friction surface treatment (HFST). A complete investigation was conducted on HFST samples by analyzing the aggregate morphology using the Aggregate Image Measurement System and performing Micro-Deval abrasion testing. The skid resistance was evaluated with the British Pendulum Tester (BPT). The findings revealed that different aggregates and sizes exhibited varying behaviors post-polishing. Notably, fine-sized aggregates demonstrated higher British pendulum number (BPN) values, which indicate superior frictional performance. Models that predicted skid numbers based on the average texture and angularity indices initially demonstrated the balanced influences of both morphological properties before polishing. However, after polishing, the surface texture emerged as the primary determinant of the skid resistance, which overshadowed the angularity’s impact.
... Numerical modelling, specifically FE modelling, has been recognized for its successful modelling of complex problems such as tire pavement interaction. Modelling tires for the FE simulations has evolved through four stages: static load, uniformly moving load step, 2D tire model [1], and 3D tire model [2]. However, the first three models inadequately capture the intricate tire structure and non-linear tire pavement interactions. ...
Conference Paper
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This study presents finite element (FE) modelling of tire pavement interaction based on a micromechanical pavement surface. The FE model of the pavement surface is created using CT scan images of an actual pavement specimen to accurately represent the micromechanical surface morphology of the pavement. The micromechanical FE model of the pavement consists of aggregate, binder, and air voids. Using the micromechanical pavement model, tire pavement interaction simulations are performed using ABAQUS by setting binder and rubber as viscoelastic materials and aggregate as an elastic material. Moreover, the FE model includes layers of asphalt, base course, and subgrade to mimic a real pavement. The interaction between tire and the pavement surface is modelled via the surface-to-surface contact.
... Pavement structure is known for its inhomogeneity and rough surface. However, many studies (Sarkar 2016, Wollny et al. 2016, Wang et al. 2017, Yu et al. 2017, Hernandez and Al-Qadi 2017a, Marais and Venter 2018, Jayme and Al-Qadi 2021, Király et al. 2022, Zhang et al. 2023) approximated the pavement model as a homogeneous flat surface layer, disregarding pavement surface characteristics, inhomogeneity and viscoelasticity. On the other hand, some models (Zhu et al. 2017, Yu et al. 2022, Zheng et al. 2022, Liu et al. 2023) presented pavements as rough surfaces but neglected the proper representation of pavement microtexture and inhomogeneity. ...
Article
This work presents a finite element model of the thermo-mechanical behaviour of tyre–pavement interaction, focusing on the effects of temperature variations in the UAE on skid resistance under various tyre operating conditions. The pavement is modelled as multiple layers to account for the stiffness contribution of each layer. The top asphalt layer is modelled at a microscale level to consider its various constituents such as air voids, aggregates and binder. Moreover, the model accounts for the viscoelastic properties of tyre and pavement, considering their dependence on time and temperature. The finite element simulations of a rolling tyre over the pavement have been carried out under different tyre operating conditions and various temperature cases reflecting the winter, spring, and summer seasons in the UAE. The simulation results show that the maximum level of skid resistance occurs during the winter season and thereafter drops by a significant amount during the summer. This research provides good insights about the seasonal variation of skid resistance in the UAE, which enhances road safety.
... Numerical modelling, specifically FE modelling, has been recognized for its successful modelling of complex problems such as tire pavement interaction. Modelling tires for the FE simulations has evolved through four stages: static load, uniformly moving load step, 2D tire model [1], and 3D tire model [2]. However, the first three models inadequately capture the intricate tire structure and non-linear tire pavement interactions. ...
... (1) Fundamentals of TDFA operation As shown in Fig. 5, the tire-road dynamic friction test system (TDFA) mainly consists of a hydraulic energy supply system, a power transfer system, a sensing system, and the supporting analysis software FICAC [29]. ...
... The simulation model of the dynamic friction due to tire-pavement contact was created in a three-step process. Specifically, a 3D model was built, then the steady state of the kinetic contact was analyzed in ABAQUS/Standard solver based upon static contact [63]. Considering the steady-state rolling analysis of a tire of ABAQUS 6.10 Example Problem Manual [64], three steps were used to create the 3D models of grooving radial tires: (1) simplification before modeling, (2) importing a 2D tire cross-sectional model into ABAQUS, and (3) 3D model generation of pneumatic tire [60]. ...
Article
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A new proposal has been applied using Bridge Information Modeling associated to Terrestrial Laser Scanning TLS and photogrammetry to obtain the digital model of an existing bridge. For the laser scanning process. Thus, it was also possible to identify the pathologies and damages in the concrete of the bridge. Furthermore, it was shown how geo-information with remote sensing using the station Trimble SX 10 can be applied in area of bridge projects with less time and lower cost, in relationship to a conventional survey Asbuilt with manual survey in field. One of the innovations of this paper was to obtain the digital model of the bridge by integration of TLS and photogrammetry to obtain the 3D digital model. The new methodology consisted of acquisition of the bridge scenes through points previously implanted, making the polygonal contour of the entire bridge. Furthermore, the execution of the field survey from georeferenced points to capture the scenes during the sweep with TLS facilitated the refinement and, consequently, it was possible to obtain the digital model with the concrete damage. It was also possible to perform a complex nonlinear analysis with Finite Element with the digital model of the bridge. Therefore, it was applied a reverse analysis of the strength of the structure using the Concrete Damage Plasticity Model using ABAQUS software. Two numerical analyses were performed on the bridge; one considering only the static behavior of the bridge and another considering the dynamic behavior. In the static analysis, the behavior of the dapped-end beam of the bridge, was investigated. On the other hand, in the dynamic evaluation, the natural frequency and damping ratio for bridges with Dapped-end beams was obtained in ABAQUS through Rayleigh damping and compared with the technical literature, which presented satisfactory results.
Article
The present paper examines the mechanical characteristics at the boundary of the distribution of rubber matrix and metal and fabric fibrous materials as a distinct area in the crack braking mechanism, and their impact on the durability of pneumatic tires in the event of damage accumulation during operation. Experimental studies were conducted on the delamination of the components of the tire material composition in samples obtained from diverse locations of the car tire. The strength of the rubber matrix fibers of the metal cord was determined, which makes it possible to assess the overall strength of the tire material as a composition of reinforcing elements and the matrix during the accumulation of damage created artificially during operation. The method of experimental research is reasonably stable. The nature and behavior of the sample rupture during the tests were evaluated.
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"Filling in gradation" method has been adopted in the skeleton interlocking dense gradation design with "equi-volume replacement" method as the guiding idea for solving the problem of inadequacy of conventional gradation design methodology's direct application in the design of dry process crumb rubber modified asphalt mixture. The research on the mix design system for dry process crumb rubber modified asphalt mixture was carried out adopting the method of replacement of equi-volume aggregates with quantified crumb rubbers. The results demonstrate that the gradation has the most predominant effect on the mass loss in Cantabro test compared with the asphalt aggregate ratio, and the crumb rubber content affects least in the three factors. The results indicate that with the skeleton interlocking dense gradation and no more than 50% of the coarse rubber, the asphalt aggregate ratio increased by 0.3% on top of the original gradation, the good performance of the dry process crumb rubber modified asphalt mixture with 5.0% rubber content by the aggregate in volume can be achieved in Cantabro test. In addition, the dynamic stability can be improved distinctly when the rubber content accounts for 3.0% in volume, but then reduced with the continuous increase of rubber content.
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Previous National Aeronautics and Space Administration (NASA) Langley aircraft tire friction performance investigations indicated the primary parameter influencing dynamic tire hydroplaning was inflation pressure. Some recent studies of several tractor-trailer accidents on flooded highway surfaces, however, suggest that in addition to inflation pressure, truck tire foot-print aspect ratio (tread contact area width to length) may significantly effect dynamic hydroplaning speed. Results from these initial tests using a worn truck tire, an ASTM Specification Standard Tire for Pavement Skid Resistance Tests (E 501) and Specification for Smooth Tread Standard Tire for Special-Purpose Pavement Skid Resistance Tests (E 524) tires are discussed in this paper.
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In order to design a longer-lasting pavement, it is important for pavement designers to understand the mechanism of the vehicular loading. The main objective of this paper is to present an idealized discrete element modeling of pavement wheel interaction for better understanding traffic loading conditions. The idealized model consists of three parts: a smooth surface, a wheel, and a mass. The smooth surface simulates the pavement surface, while the wheel and mass represent a vehicle wheel and its corresponding mass, respectively. The mechanical behaviors at the interaction surface are simulated through an elastic contact model, a slip model, and a viscous contact damping model. Discrete Element simulation was performed through loading the wheel with a vertical force and a torsion moment at its center. As a result, the wheel was rotated and moved forward to simulate a vehicle rolling on the pavement surface. Through analyzing the simulation results, it was found that findings of this research were comparable with theoretical solutions and those of the finite element modeling in a previous study.
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The dry process for crumb rubber modified (CRM) asphalt mixtures is characterized by a simple construction process that results in greater environmental benefits than the wet process does. However, the difficulties of compaction in the dry process often lead to unstable pavement performance; therefore, its application is highly restricted. This research aims to investigate the compaction procedure for dry process CRM asphalt mixtures using air void content and expansion ratio as the principal indices for evaluation. To evaluate the key factors affecting compaction, a series of CRM mixtures were prepared and compacted at four different crumb rubber contents by total aggregate volume of 3.0 %, 5.5 %, 8.0 %, and 10 %. First, with the air void ratio as the target indicator, the crumb rubber content, compaction temperature, and compaction method were evaluated to determine the appropriate compaction procedure. Second, the variations in height and expansion ratio of the CRM asphalt mixture specimens with different crumb rubber contents were analyzed in order to calculate the expansion ratio. The results indicated that generally the height and expansion ratio increase as the crumb rubber content of the CRM asphalt mixtures increases. Furthermore, it was found that when the crumb rubber addition was 5.5 % of the bulk volume of minerals, the volume stability of the mixture was improved, and this value is recommended for dry process CRM asphalt mixtures.
Book
Description STP 929 contains eleven papers, which will help the reader solve transportation problems in ways that should prove cost effective. Three sections cover: the traction connection; interfacial stresses, motions, and wear; and pavement generated vibration and noise.
Article
This paper presents the findings of a study conducted to investigate the quantitative role played by small-scale surface texture (microtexture) in determining the skid resistance of a pavement. Specific objectives were to understand better the microtexture's influence on skid resistance and to determine if optimal dimensions of microtexture exist that should be sought when designing a pavement or selecting aggregate materials. Measurements of microtexture profiles were obtained on a series of pavement cores using a noncontact image analysis system in the laboratory. Correlations were determined between these measurements and British Portable Tester numbers (BPNs), obtained on the same cores. (BPNs are friction measurements believed to be closely related to microtexture.) Finally, the microtexture measurements were combined with estimated tire-contact area measurements (representing macrotexture) and the results correlated with skid resistance measurements taken on the same pavements. Correlation coefficients of up to 0.70 were attained. Examination of the data indicates that some improvement in this correlation may be possible. It is concluded that pavement microtexture can be characterized by one profile parameter. Additionally, pavement macrotexture can be characterized by estimating the percent contact a vehicle tire would have on the pavement surface in question.
Article
A state-of-the-art review of key parameters that influence measurement and modeling of skid resistance of asphalt pavements is provided. Tire-pavement interaction/friction is discussed and the current harmonization method of friction measurements questioned. The latest developments on pavement surface texture measurement and characterization are highlighted. A critical review of aggregate properties affecting friction, the frictional properties of asphalt mixtures and the influence of environmental factors on skid resistance is presented. An overview of modeling efforts entailing different aspects of tire-pavement friction is also presented. The frictional performance of asphalt pavements largely depends on the type and quality of coarse aggregates used. The different hot mix asphalt (HMA) classifications generally have similar microtextures. Their frictional performance follows the same order as their macrotextures. There is need for experimentally-validated skid resistance prediction models, especially for warm surfaces. Such models should account for tire and pavement surface texture characteristics, and the influence of environmental factors. Some other research needs are also identified.
Article
Tire–pavement friction is a factor that can affect the rate of vehicle crashes. Several studies have suggested that reduced friction during wet weather conditions, due to water on the pavement surface reducing the contact area between the tire and the pavement, increases vehicle crashes. This study evaluates the effect of friction on both wet- and dry-condition crashes. The data for the study were provided by the New Jersey Department of Transportation. Regression analysis was performed to verify the effect of friction on the rate of wet- and dry-condition vehicle crashes for various types of urban roads. It was found that friction is not only associated with the rate of wet-condition vehicle crashes, but it also impacts the rate of dry-condition vehicle crashes. The analysis also suggested that the developed regression models could be used to define the friction demand for different road categories.
Article
Accurate modeling of tire-pavement contact behavior plays an important role in the analysis of pavement performance and vehicle stability control. A three-dimensional (3D) tire-pavement interaction model was developed using the FEM to analyze the forces and contact stresses generated during vehicle maneuvering (free rolling, braking/acceleration, and cornering). A pneumatic radial-ply tire structure with rubber and reinforcement was simulated. The steady-state, tire-rolling process was simulated using an Arbitrary Lagrangian Eulerian (ALE) formulation. An improved friction model that considers the effect of sliding speed on friction coefficients was implemented to analyze the effects of pavement surface friction on contact stresses, friction forces, and cornering forces. The results showed that the magnitudes and nonuniformity of contact stresses are affected by vehicle-maneuvering conditions. As the pavement surface friction increases, the tangential tire-pavement contact stresses at various rolling conditions (free rolling, braking/ acceleration, and cornering) and the vertical contact stresses at the cornering condition increase. It is reasonable to use the constant friction coefficient when predicting tire-pavement contact stresses at the free-rolling condition or at the cornering condition with small slip angles. However, it is important to use the sliding-velocity-dependent friction model when predicting the friction force at tire braking. (C) 2014 American Society of Civil Engineers.
Article
This paper investigates the pavement friction–texture relationship, using a decomposition method of the pavement texture that is part of a new signal processing technique called ‘Hilbert–Huang transform’ to develop a texture parameters–friction relation. This method allows the empirical decomposition of the texture profile to a set of basic profiles in a limited number, called ‘intrinsic mode functions’ or IMFs. From the obtained IMFs, a set of four new functions called ‘base intrinsic mode functions’ or BIMFs, are introduced and are characterised from the density and sharpness of the peaks contained in the individual BIMFs. Then these two parameters are correlated with the pavement friction using different combinations. This procedure is applied to a set of texture and friction data measured through test roads in France. The textures and frictions are measured using, respectively, the Circular Texture Meter and the Dynamic Friction Tester in France and also on a number of test sites in the USA. The obtained results show a good correlation between some of the BIMF parameters (density and sharpness) and friction.