Marcin Gajewski

Warsaw University of Technology / Road and Bridge Research Institute / · Strength of Materials and Theory of Elasticity & Plasticity/ Pavement Technology

A theoretical model for an elastic anisotropic composite of road mixtures reinforced with grids together with its isotropic approximation is proposed. In the considered models, some elements of the mechanics of fibrous composite materials and optimisation theory are used. A composite model is an energy model; that is, constitutive relationships res...

In this chapter, a state of the art on the basics of the fatigue phenomenon of engineering materials are presented, with special attention to asphalt materials and bituminous binders. Since engineering materials are exposed to complex mechanical and environmental loadings (e.g. temperature and humidity variationetc.) asphalt mixture fatigue tests h...

W budownictwie drogowym badanie FWD (Falling Weight Deflectometer) jest jednym ze sposobów oceny nośności podłoża (podbudowy drogi), nawierzchni przed remontem oraz wykonanej nawierzchni w ramach jej diagnostyki. Jest to badanie, które w stosunkowo prosty sposób można przeprowadzić, a potrzebny sprzęt w porównaniu np. z ugięciomierzem laserowym TSD...

This paper presents results of field tests performed in Poland within SPENS project. The test sections were built in Poland (October 2007). All of construction works as well as research tests were conducted in cooperation with the Swedish National Road and Transport Research Institute (VTI), STRABAG, TPA, Lafarge and ORLEN. The test section was div...

This paper presents the results of resilient moduli tests carried out on selected hydraulically bound mixtures (HBM). Both static and dynamic loading procedures were used. In total, thirteen hydraulically bound mixtures designed for construction of road base and subgrade improvement were tested. The mixtures were composed of crushed granite, dolomi...

Jedną z metod wzmacniania gruntu jest wzmacnianie podłoża gruntowego kolumnami sztywnymi typu RI (Rigid Inclusions). Używa się również kilka innych nazw – firmowych, w tym m.in. kolumny CMC (Controlled Modulus Columns) oraz kolumny CSC (Controlled Stiffness Columns). Wiele wdrożeń w Polsce pozwala na stwierdzenie, że metoda kolumn sztywnych ma swoj...

This paper presents the results of a research study and analysis conducted to determine the degree of anisotropy of asphalt concrete in terms of its initial elastic properties. The analysis of asphalt concrete was focused on determining the effective constrained stiffness modulus in three mutually perpendicular directions based on the finite elemen...

The paper presents the assessment of the properties of high modulus asphalt concrete in low service temperature range. Such an assessment is particularly important due to the climatic conditions of Poland and the problem of the occurrence of thermal cracking in recent years. The scope of laboratory tests included both resistance to low temperature...

The paper presents solutions for thermo-elasticity problems with an unsteady heat flow for various layered systems typical for Polish traffic categories KR4 and KR7. The tasks were solved assuming a plain strain case for material parameters, which in most cases were determined in a laboratory tests, under thermal type of loading, which simulates an...

The paper presents modeling of bridge elastomeric bearings using large deformation theory and hyperelastic constitutive relations. In this work, the simplest neo-Hookean model was compared with the Yeoh model. The parameters of the models were determined from the elastomer uniaxial tensile test and then verified with the results from experimental b...

In this paper, a three-dimensional model of nonlinear elastic material is proposed. The model is formulated in the framework of Green elasticity, which is based on the specific elastic energy potential. Equivalently, this model can be associated to the deformation theory of plasticity. The constitutive relationship, derived from the assumed specifi...

Concretes with dispersed reinforcement are increasingly used in structural engineering. The basic source of knowledge on their application and design are the Model-Code 2010 guidelines. These guidelines, however, apply mainly to steel rebar reinforcement and are not fully sufficient in the analysis of the load-bearing capacity of elements made of c...

Polymer-modified binders (PMB) have been known and used for many years to increase asphalt pavement durability. The most commonly used polymer is the SBS elastomer (styrene–butadienestyrene). Its content in the classic polymer-modified binder ranges from 2 to 4% m/m (by weight). In such a case, it fills up to 40% of the binder’s volume to form a po...

When designing embankments on a soft ground improved with columns (rigid inclusions) and with a geosynthetically reinforced load transfer platform (LTP), the methods of determining strains in reinforcement reduce the spatial problem to a two-dimensional one, and analytical calculations are carried out for reinforcement strips in the directions alon...

Steel prismatic elements of equal flanges double-tee section subject to major axis bending and compression, unrestrained in the out-of-plane direction between the supports, are vulnerable to buckling modes associated with minor axis flexural and torsional deformations. When end bending moments are acting alone on the quasi-straight member, the sens...

The main goal of introducing the MSCR test was to estimate the rheological properties of pen grade and modified binders using the same measure. The conditions for this test were chosen at random (the length of creep and recovery period, the stress levels, as well as the test temperature). In most applications, the test temperature value was equal t...

The distribution of the equivalent load in the analysis of the reinforcement of an embankment load transfer platform on a soft soil reinforced with columns has an impact on the behaviour of the membrane modelling this reinforcement. Depending on the calculation model, triangular, uniform and inverse triangular distributions are commonly used. The p...

The formulations of tasks modelling embankments on soft soil, improved with columns and with reinforced load transfer platform (LTP), differ significantly. One of these differences is the distribution of equivalent load modelling part of the load carried by the LTP reinforcement and soft soil. This article analyses the influence of the nature of th...

The paper deals with determination of flexural resistance buckling curves for welded I-section steel members made of high strength steel (S 690). In the paper the previously proposed BF analytical model is used for approximation of FEM results obtained using moderately large deformation shell theory and ABAQUS/Standard software. Final formulation o...

This chapter is a development of the considerations presented in previous Author's works, where the estimation of the approximate method for strains and forces evaluation from the membrane effect in reinforcement of embankments on columns was presented. In above mentioned Author's work accuracy of the proposed approximate method was verified in ref...

The chapter presents results of modelling of compressed perforated thin-walled bars of very low slenderness, especially final element method analysis on influence of imperfections is conducted. The displacement type of boundary conditions are used (the compressive force is interpreted as the resultant reaction force for the applied displacement typ...

The monograph Mechanics of Materials and Structures is the IX volume of the series Theoretical Foundations of Civil Engineering and the third edited in English. The monograph consists of eleven chapters, which are predominately extended versions of the selected papers presented at the XXVIII Russian-Polish-Slovak Seminar. Several issues concerning...

This article presents the results of a systematic comparison of predictions of the thin-walled beam theory and shell theory in the context of bending of elastic thin-walled beams with an open or closed cross-section. The results for shell theory were obtained using FEM and the ABAQUS/Standard program. The bending task of the thin-walled beam was de...

This article presents a method of approximate finding of forces and strains resulting from the so-called membrane effect in the reinforcement of the transmission layer of embankments located on a soft soil improved by columns (rigid inclusions). The model task needed to determine the characteristic values in geosynthetic reinforcement supported on...

The main goal of the analysis presented in the following chapter is an estimation of the analytical solutions, resulting from classical theory of thin walled bars with open cross-sections, in view of solutions obtained with application of the finite element method (FEM). The mentioned estimation was done on the basis of the one span steel beam with...

The critical moment analytical expressions used in engineering design are based on the thin-walled beam model of warping torsion and the linear eigenvalue analysis (LEA) while the analytical formulation of the buckling curve equation follows the Ayrton-Perry model with the Maquoi-Rondal initial imperfection parameter. Using the equivalent geometric...

H-section beam-columns under compression and bending moment about their stronger principal axis are generally sensitive to flexural-torsional buckling when insufficiently restrained against lateral-torsional deformations. Depending upon the section inertia properties about principal axes and the proportion between the compressive axial force and th...

A novel analytical model is proposed for establishing design criteria based on the decomposition of the in-plane deformation and out-of-plane stability states. First part of this study considered the in-plane buckling resistance of beam-columns. This study uses the results from Gizejowski et al. [Buckling resistance of steel I-section beam-columns:...

Buckling resistance predictions resulting from flexural and flexural-torsional buckling of double tee section members subjected to compression and bending are considered. A novel analytical model is developed for establishing design criteria based on decomposition of the member buckling behaviour into in-plane and out-of-plane resistance. The forme...

Pręt cienkościenny traci zdolność przenoszenia zwiększającego się obciążenia ze względu na utratę stateczności lokalnej lub globalnej. Utracie stateczności towarzyszy powstawanie dużych deformacji zwykle przy małych odkształceniach sprężystych. W miarę narastania de-formacji mogą się również pojawić odkształcenia plastyczne. W przypadku ściskania c...

Rozdział ten stanowi kontynuację prezentacji zagadnień związanych ze statecznością cienkościennych elementów poddanych ściskaniu zamieszczonych w Rozdziale XII niniejszej monografii [2]. W odróżnieniu od rozwiązań tam przedstawionych, w tym rozdziale uwzględniono właściwości plastyczne stali [6, 10, 15, 17, 20, 32], z której wykonane są cienkościen...

W tym rozdziale podamy przykłady zastosowania pakietu MATLAB, a właściwie dołączonego do niego programu Partial Differential Equation Toolbox (PDE) z 1996 r. [24] oraz programu SYSTUS-SYSWELD [20-22] z 2000 roku. Stosujemy wyniki naszych prac [5,6,7,11,12] publikowanych w materiałach konferencyjnych. Należy zaznaczyć, że obecnie program PDE jest ni...

Uwzględnienie przenikania ciepła przez przegrody jest istotnym zagadnieniem w projektowaniu budowli [3-7,9,10,14,17,18,22,24,30]. Podstawowe przypadki ustalonego i nieustalonego przepływu ciepła przez jednorodne izotropowe przegrody mają rozwiązania analityczne [18,21,28]. W sytuacji natomiast materiałów niejednorodnych i złożonych warunków brzegow...

W rozdziale tym rozpatrujemy przykład testowy metody elementów skończonych (MES) zaproponowany w naszym artykule [2], w którym analizujemy drgania własne kamertonu,. Kamerton jest przyrządem służącym do ustalania wzorcowego stroju instrumentów. Wykonany jest on w formie stalowych widełek, patrz rys.1.1, wprawianych w wibrację przez uderzenie i wyda...

Kompozyty włókniste Materiały kompozytowe powstałe przez zbrojenie włóknami izotropowej matrycy są obecnie powszechnie stosowane w technice [3]. Typowymi kompozytami włóknistymi są materiały o osnowie polimerowej. Funkcję osnowy pełnią zwykle żywice syntetyczne (np. żywice epoksydowe lub poliestrowe), włókna zaś są najczęściej szklane, węglowe, bor...

W klasie anizotropowych relacji konstytutywnych materiałów nieliniowo-sprężystych teorii małych odkształceń (TMO), bardzo ważnym typem ich symetrii względem transformacji ortogonalnych jest transwersalna izotropia (TRI), por. [3,6] i literaturę tam cytowaną. Spośród pięciu podgrup symetrii transwersalnej izotropii, teoretycznie możliwych w zagadnie...

Zagadnienie brzegowe liniowej teorii sprężystości materiałów anizotropowych sprowa-dza się w sformułowaniu przemieszczeniowym do rozwiązania układu eliptycznych równań różniczkowych cząstkowych z warunkami brzegowymi Dirichleta lub Neumanna [9]. Metodami analitycznymi nie uzyskamy rozwiązania powyższego zagadnienia dla szerokiej klasy zadań, dlateg...

Zagadnienia związane z modelowaniem konstytutywnym hipersprężystych materiałów anizotropowych są ostatnio coraz częściej rozpatrywane, np. w mechanice kompozytów o elastomerowych matrycach, biomechanice miękkich tkanek oraz teorii sprężysto-plastyczności dowolnych deformacji, por. [4,6,7]. Sformułowanie modeli materiałów anizotropowych, z zastosowa...

Zagadnienie wyznaczenia trajektorii wartości własnych płaskich pól tensorowych drugiego rzędu ma podstawowe znaczenie w analizie pracy konstrukcji tarczowych i płyto-wych. W celu racjonalnego kształtowania albo zbrojenia konstrukcji w tarczach wyznacza się np. trajektorie naprężeń głównych zaś w płytach trajektorie momentów głównych. Znalezienie wa...

W symulacjach numerycznych MES uwzględniających duże deformacje sprężysto-plastyczne bardzo istotne jest wybranie do analizy danego zadania właściwego modelu mate-riału i określenie parametrów tego modelu. W programach MES wykorzystywanych do anali-zy elementów konstrukcji, standardowo dostępnych jest wiele modeli konstytutywnych (por. np.[1]. Stos...

Hipersprężystość materiałów izotropowych, uzupełniona o prawo kontaktu deformujących się ciał, jest obecnie teorią dość dobrze ugruntowaną teoretycznie. Odpowiednie sformułowanie wariacyjne tego zadania nie jest zagadnieniem wypukłym, co prowadzi do możliwości wieloznacznych rozwiązań. W pewnych szczególnych przypadkach istnieją dowody o istnieniu...

Kompozyty włókniste Materiały kompozytowe powstałe przez zbrojenie włóknami izotropowej matrycy są obecnie powszechnie stosowane w technice [3]. Typowymi kompozytami włóknistymi są materiały o osnowie polimerowej. Funkcję osnowy pełnią zwykle żywice syntetyczne (np. żywice epoksydowe lub poliestrowe), włókna zaś są najczęściej szklane, węglowe, bor...

The paper presents an analysis of a flexible road pavement with a concrete pipeline running along the road axis, just under the pavement. The subgrade of such a pavement cannot be regarded as homogenous and the design cannot be limited to merely the selection of a catalogue pavement structure or to the direct application of the mechanistic-empirica...

The fatigue life of an asphalt mix is defined as the number of load repetitions at which the crack initiation phase ends and macro cracks start to grow (crack propagation/failure phase). The problem is how to determine in an objective way this number of repetitions. Three different definitions for the fatigue life were applied and compared to each...

In this paper, we analyse various minimization algorithms applied to the problem of determining elasto-plastic material parameters using an inverse analysis and digital image correlation (DIC) system. As the DIC system, ARAMIS is used, while for the finite element solution of boundary value problems, Abaqus software is applied. Different minimizati...

This paper discusses different aspects of analytical and numerical modelling of the buckling resistance of welded I-section columns subjected to axial compression. The section considered is of class 1 that implies no local buckling affecting the column performance. The proposed analytical formulation of the buckling resistance is based on the so-ca...

Laterally and torsionally unrestrained steel I-section beams are susceptible to torsional deformations between supports; therefore, according to Part 1-1 of Eurocode 3, they need to be designed to resist lateral-torsional buckling. Eurocode’s steelwork design criteria require safety checking based on two stability interaction formulae utilizing the...

This paper analyzes the influence of geometrical and material imperfections on the buckling resistance of welded I-section columns subjected to axial compression through numerical and analytical models. The paper is divided into two parts. The first part recalls a FEM parametric study of members under compression taking into account different slend...

The capability of material for energy dissipation is determined through analysis of the complex stiffness moduli. The imaginary part of complex stiffness modulus is proportional to energy dissipation per volume material unit. This estimation is justified when material works in its linearity range (the Boltzman principle is satisfied). In case when...

The paper deals with finite element modelling of the test carried out on plate samples made of asphalt mixture and reinforced with glass grid. The apparatus constructed for testing of plate samples in the large scale is modelled in detail as a contact problem. All materials are assumed to be linearly elastic and isotropic, and stiffness modulus of...

The paper presents comprehensive results of the performance and non-standard rheological tests of chosen paving-grade bitumens modified by adding natural asphalt. It has been demonstrated that standard performance tests give the same classification rating to bitumens that have considerably different rheological properties. In such situations it is...

In the presented paper the local instabilities occurring in compression test of perforated thin-walled bars of low slenderness are observed using digital image correlation system ARAMIS. The tested samples slenderness is so low, that from theoretical point of view we are dealing with compression tests of some perforated shells. The samples are made...

This paper analyzes the influence of geometrical and material imperfections on the buckling resistance of welded I-section columns subjected to axial compression through numerical and analytical models. The paper is divided into two parts. The first part recalls a FEM parametric study of members under compression taking into account different slend...

The paper contains a review of hydraulically bound layers fatigue resistance criteria that are commonly applied in designing the road pavement structures. The effect of the mechanical parameters applied in the respective criteria on the obtained fatigue resistances is analysed with their different nature underscored. Most of the fatigue criteria de...

The paper presents an analysis of a flexible road pavement with a concrete pipeline running along the road axis, just under the pavement. The subgrade of such a pavement cannot be regarded as homogenous and the design cannot be limited to merely the selection of a catalogue pavement structure or to the direct application of the mechanistic-empirica...

Wydanie drugie monografii: https://www.researchgate.net/publication/273734184_Hyperelasto-plasticity_Hipersprezystoplastycznosc Poprawione i uzupełnione.

The paper deals with the processing of the data of the four point bending tests carried out for determination of material properties. The tests are interpreted throughout the Bernoulli’s beam theory with neglecting dynamical influences at the start of the test. Presented interpretation is done mainly for problems dealing with determination of visco...

Present Eurocode's approach to design of steel I-section beams is based on the analytical resistance evaluation yielding from the interaction resistance criteria established for beam-columns that cover two design situations: a) the flexural in-plane failure (second order biaxial bending and compression), and b) the flexural-torsional out-of-plane f...

This paper attempts to verify the Eurocode's buckling resistance criteria in case of rolled I- and H-sections in monoaxial bending about their major axis using finite element simulations and two imperfection modelling techniques, namely a) using the equivalent geometric imperfection concept in which the effect of material and geometrical imperfecti...

W pracy przedstawiono zagadnienie wpływu imperfekcji materiałowych i geometrycznych na techniczne zwichrzenie stalowych belek walcowanych i spawanych poddanych jednokierunkowemu zginaniu względem osi większej bezwładności przekroju y-y. Obliczenia metodą elementów skończonych przeprowadzono w odniesieniu do belek walcowanych na gorąco wykonanych z...

Celem tego rozdziału jest ilustracja zagadnienia wyznaczenia trajektorii naprężeń i odkształceń głównych w zagadnieniach płaskich liniowej teorii sprężystości materiałów anizotropowych. W punkcie 2 krótko przypominamy podstawowe wiadomości i równania konieczne do sformułowania zagadnień brzegowych teorii sprężystości w przypadku tarcz płaskiego sta...

The authors focused on buckling resistance assessment of steel-I-section perfect beam-columns of the cross-section class 1 and 2, not susceptible to LT-buckling and subjected to compression and one directional bending about the section principal axes y–y or z–z. These assumptions lead to the case of elements considered as only sensitive to the flex...

Welding is the most important joining technique and offers the advantage of customizable plate thicknesses. On the other hand, welding causes residual stresses and deformations influencing the load carrying capacity. Their consideration in the design requires simple and fast models. Though welding simulation has contributed to accurately access to...

The paper presents the results of rheological testing performed with the use of DMA (Dynamic Mechanical Analyser) rheometer on specimens made of natural rubber (NR) and synthetic rubber (CR) elastomeric materials typically used for production of bridge bearings. The experiments provided the values of complex stiffness modulus and phase shift angles...

In the paper two classes of poly-convex stored energy functions for transversally isotropic hyper-elastic materials have been proposed. Within these classes, a simplified model of hyper-elastic materials with an isotropic matrix reinforced with fibre family was derived and implemented in finite element software ABAQUS/Standard. The two numerical ex...

[Inżynieria i Budownictwo 1 (2017) 13-17] Przedstawiono zagadnienia sprężystej i sprężysto-plastycznej niestateczności ogólnej belek stalowych poddanych jednokierunkowemu zginaniu w płaszczyźnie większej bezwładności przekroju. Wskazano na potrzebę uogólnienia podejścia eurokodowego oraz zaproponowano metodę weryfikacji zwichrzenia belek stalowych...

Abstract Transportation noise has a growing detrimental impact on the environment, humans health and living conditions. In addition to noise mitigation by erection of the expensive noise barriers, tire/pavement noise can be reduced “in source” by construction of special asphalt pavements. While that solution is commonly known in regions with modera...

Evaluation of the lateral-torsional buckling resistance of bisymmetrical I-section beams using finite element method was widely discussed in the paper. Numerous FEM simulations with regard to the stability behavior of steel structural elements subjected to bending about the major principal axis were performed. The use of different finite element mo...

Assessment of the flexural buckling resistance of bisymmetrical I-section beam-columns using FEM is widely discussed in the paper with regard to their imperfect model. The concept of equivalent geometric imperfections is applied in compliance with the so-called Eurocode’s general method. Various imperfection profiles are considered. The global effe...

The main objective of this study is to estimate the accuracy of the method for the determination of material parameters based on laboratory data from a single experiment conducted on a sample working in a nonuniform stress state, registered by the digital image correlation system (DIC). The idea of the method is based on the inverse analysis, in wh...

Elastic properties of rubber-like materials with limiting extensibility can be characterized by means of strain energy function and locking condition. One can show that the Gent’s model cannot be used for relatively large stretches and provides poor approximation of experimental data. The basic aim of the present paper is to propose a generalizatio...

In this paper, a simple method is proposed to estimate capacity of multilayered road structure including the degradation of the elastic and plastic properties of the constituent materials. In the study boundary value problem modeling interaction of wheels with road surface layer in the frame of large deformation theory for elastic-plastic materials...

Present approach to design of steel I-section beam-columns distinguish two design situations of elements subjected to two directional bending about their principal major axis and compression in which they are sensitive to: a) the flexural failure (second order spatial bending and compression) or b) the flexural-torsional failure (second order spati...

The subject of this paper is the structural analysis of a concrete airfield pavement with doweled joints after curling focusing on the doweled joints behaviour. The paper presents some examples of such pavement structures and dowel bar installation. Attention is paid to the effects of curling of slabs due to the temperature gradient across the slab...

The fatigue property of an asphalt mix is an important issue in pavement design. This property is often determined with the aid of a four-point bending (4PB) test in controlled deflection mode. The fatigue property is related to the decrease in the calculated complex stiffness modulus, however, due to the non- homogenous stress and strain field in...

Przedstawiono metody symulacji statecznościowego zachowania się zginanych elementów konstrukcji stalowych z wykorzystaniem modelowania skończenie-elementowego. Rozważania dotyczą belek nieidealnych, wykonanych z walcowanych kształtowników szerokostopowych HEB i wąskostopowych IPE, o wstępnym wygięciu odpowiadającym pierwszej formie zwichrzenia. Ide...