Armin Stuedlein

Armin Stuedlein
Oregon State University | OSU · Department of Civil and Construction Engineering

Doctor of Philosophy

About

133
Publications
36,613
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
2,125
Citations

Publications

Publications (133)
Conference Paper
Soil liquefaction and resulting ground failure due to earthquakes presents a significant hazard to distributed infrastructure systems and structures around the world. Currently there is no consensus in liquefaction susceptibility or triggering models. The disagreements between models is a result of incomplete datasets and parameter spaces for model...
Conference Paper
Current best practices for the assessment of the cyclic response of plastic silts are centered on the careful sampling and cyclic testing of natural, intact specimens. Side-by-side evaluation of in-situ and laboratory element test responses are severely limited, despite the need to establish similarities and differences in their characteristics. In...
Article
The effect of strain history on monotonic and cyclic response of intact and reconstituted, low and high plasticity silt deposits have been investigated through a series of constant-volume, staged, stress- and strain-controlled cyclic direct simple shear tests. In many cases the specimens subjected to stress-controlled loading exhibited a progressiv...
Article
Liquefaction-induced reconsolidation settlements occur as excess pore pressures generated during shaking dissipate and can lead to significant damage to overlying infrastructure. Designing resilient infrastructure in areas affected by liquefaction requires methods to predict these settlements for different soil types and boundary conditions. Simpli...
Article
Full-text available
A homogeneous microfluidic chip was used to investigate the pore-scale characteristics during the process of microbially induced calcium carbonate precipitation (MICP). An image-processing scheme was developed to measure the projecting areas of the precipitated calcium carbonate. Calcium carbonate first precipitated on the bacterium side before spr...
Article
Full-text available
In a previous work, the first two authors proposed a data-driven method that can construct a site-specific multivariate probability density function model for soil properties using sparse, incomplete, and spatially variable site investigation data. The spatial variability was limited to the depth direction (horizontal variability was not considered...
Article
Full-text available
A thermodynamics-based constitutive model is developed for calcareous sand treated by microbially-induced calcite precipitation (MICP) to describe the effects of biocementation and its degradation by cyclic shearing within the framework of non-equilibrium thermodynamics. The elastic potential function implemented within the constitutive model leads...
Article
This study presents a novel test method to obtain dynamic properties of soil in-situ using controlled blasting. Experimental and calibration protocols have been developed to conduct such investigations for any soil at any depth to obtain the coupled response between nonlinear shear modulus and pore pressure generation in soil. Controlled blasting u...
Article
This technical note aims to investigate the effects of biotreatment on the response of a concrete model pile embedded in poorly graded sand through lateral loading tests. The bending moment profiles along pile length were obtained from strain gauges collected during the pile load tests. The pile deflection and soil resistance were derived from a be...
Article
Full-text available
The 2018 M w 7.1 Anchorage, Alaska, earthquake is one of the largest earthquakes to strike near a major US city since the 1994 Northridge earthquake. The significance of this event motivated reconnaissance efforts to thoroughly document damage to the built environment. This article presents the spatial variability of ground motion intensity and its...
Conference Paper
Experimental studies have demonstrated that the stiffness and bearing capacity of conventional stone columns can be significantly increased by using cement-coated aggregate. However, there are still uncertainties regarding the global performance, load transfer mechanisms, and design of cemented stone columns under various field conditions. Results...
Conference Paper
The p–y method for analysis of the lateral load transfer of deep foundations has been widely accepted in the geotechnical profession. However, the p–y models typically used are often based on one or several full-scale, instrumented loading tests in a specific soil deposit and may not be appropriate for other deposits that exhibit differences in soi...
Conference Paper
The performance of improved ground during earthquakes continues to receive high interest in the geotechnical earthquake engineering profession given the need to establish best design and construction practices associated with ground improvement technology. The M7.1 30 November 2018 Anchorage earthquake produced significant shaking intensity at the...
Article
Full-text available
Microbially induced carbonate precipitation (MICP) has been actively investigated as a promising method to improve soil properties. A burning issue impeding its wide application is the severe spatial inhomogeneity of the CaCO3 distribution. Inspiring by the temperature sensitivity of the bacteria activity, a temperature-controlled one-phase MICP me...
Article
Progressive and standing waves can produce instability of the seabed and seabed-supported marine structures. In this paper, the stress paths induced by standing waves were deduced to provide a theoretical basis for laboratory element tests to establish the cyclic behavior of marine sediments, which can serve to improve the understanding of seabed l...
Article
This study presents the use of controlled blasting for the determination of the in-situ dynamic response of a sand deposit at a depth of 25 m under effective overburden stresses of approximately 250 kPa. The experiments were performed to establish the suitability of blasting as a seismic energy source for the quantification and evaluation of dynami...
Article
This study presents the use of controlled blasting as a source of seismic energy to obtain the coupled, dynamic, linear-elastic to nonlinear-inelastic response of a plastic silt deposit. Characterization of blast-induced ground motions indicate that the shear strain and corresponding residual excess pore pressures (EPPs) are associated with low fre...
Article
Driven timber displacement piles are being increasingly used to densify and reinforce soils against earthquake-induced ground deformations. However, the role of timber piles to reinforce the soils and redistribute cyclic stresses to timber piles has not been established, despite their excellent flexural properties. This study presents a series of d...
Article
Lightweight expanded clay aggregate (LECA) is a geomaterial that is low in density, porous, and has an enamel surface. A series of unconfined compression and resonant column tests were performed to understand the dynamic performance of LECA. Testing results show that the uncemented LECA is poorly graded but possesses a stable internal structure. Th...
Article
This study presents a comprehensive investigation into the monotonic, cyclic, and postcyclic response of a medium stiff, plastic, lightly-overconsolidated, alluvial clayey silt deposit. The laboratory investigation is performed on natural, intact, and reconstituted specimens derived from high-quality samples to establish the role of the stress hist...
Article
Observations of the performance of coastal and marine structures in weather events that produce standing and/or progressive waves have pointed to liquefaction of the seabed as a contributing cause of damage. The cyclic response of marine sediments under wave loading can serve to improve the understanding of seabed liquefaction triggering and its co...
Article
Full-text available
The particle breakage and compressibility behavior of sands treated with microbially induced carbonate precipitation (MICP) has been investigated using oedometric compression tests. The acid washing technique was used to obtain the calcium carbonate (CaCO3) content and facilitate quantification of particle breakage by measurement of the particle si...
Article
Changes in soil fabric following liquefaction have been studied using various in-situ methods, and often return inconclusive or conflicting observations. The time-rate variation of stiffness, when observed, is usually not evaluated over significant periods of time, limiting investigations about aging in post-liquefaction regain of stiffness. Even m...
Article
Full-text available
The empirical approach adapting the Stress History and Normalized Soil Engineering Properties (SHANSEP) concept relates the average overconsolidation ratio (OCR) of plastic soils to the average pile side adhesion normalized to the effective overburden stress. Additional pile case histories were identified and used to expand an existing database and...
Article
This technical paper investigates the bearing performance of precast concrete piles embedded within calcareous sands with biogrouting at the pile toe. Loading tests of biogrout-improved and unimproved concrete model piles were conducted to evaluate the performance of biogrout to enhance the toe bearing capacity of precast concrete piles. The total...
Article
Full-text available
Grain crushing is commonly encountered in deep foundation engineering, high rockfill dam engineering, railway engineering, mining engineering, coastal engineering, petroleum engineering, and other geoscience application. Grain crushing is affected by fundamental soil characteristics, such as their mineral strength, grain size and distribution, grai...
Conference Paper
The moment magnitude (Mw) 7.1 Anchorage, Alaska, earthquake on November 30, 2018 is one of the largest earthquakes to strike near a major U.S. city since the 1994 Northridge earthquake. No fatalities were reported, but the earthquake caused widespread power outages, structural damage to residential buildings, damage to roadways and railways, and gr...
Article
Full-text available
Microbial-induced calcium carbonate precipitation (MICP) represents a promising approach to improve the geotechnical engineering properties of soils through the precipitation of calcium carbonate (CaCO3) at soil particle contacts and soil particle surfaces. An extensive experimental study was undertaken to investigate the influence of initial relat...
Conference Paper
Full-text available
Assessment of earthquake-induced liquefaction is an important topic in geotechnical engineering due to the significant potential for damage to infrastructure. Assessments of liquefaction triggering and estimation of post-liquefaction deformations is commonly done using empirical models, which often assume laterally homogeneous soil layers. Numerica...
Article
Full-text available
Recent studies have shown that the sample path smoothness in soil spatial variability can have a significant effect on the failure probability of geotechnical problems. The purpose of the current study is to propose a procedure that can identify the sample path smoothness based on site investigation data. It is shown that two factors determine whet...
Article
Full-text available
Calcareous sands are known as problematic soils in nature and challenge geotechnical engineers in many practical projects. Microbially-induced calcite precipitation (MICP) is an innovative soil improvement technique that uses biomineralisation processes to induce cementation in-situ. The work described in this paper investigates the strength, defor...
Article
Increased seismic flexural demands on drilled shaft foundations have led to significant increases in the amount of steel reinforcement, leading to a greater number and/or larger sized steel bars and increased possibility of anomalies within drilled shafts due to reduced apertures between the reinforcement for concrete passage. High-strength steel r...
Article
Full-text available
Microbially induced calcite precipitation (MICP) has attracted significant attention as a promising in situ ground reinforcement method, particularly for the improvement of existing structure foundations. Prior to its widespread application, further study is required to answer questions that seek to improve understanding of the fundamental mechanis...
Article
Recent 1-g shake table experiments have shown that the relatively new X-shaped cast-in-place piles can improve the seismic response of slopes susceptible to lateral-spreading as compared to conventional bored piles when mitigated using the pile-pinning method. This paper presents three-dimensional (3D) nonlinear dynamic numerical simulations of gro...
Article
Full-text available
The crushing behavior of carbonate sand, due to its porous and fragile structure, exerts a significant influence on the construction of coastal engineering. The collapse of porous material usually produces elastic wave dissipation and force drop in stress-strain curves. To study the acoustic and mechanical characteristics of carbonate sand crushing...
Article
Full-text available
The strength properties of basalt fiber-reinforced biocemented (BFRB) sand specimens with various calcite contents and fiber contents are investigated through a series of unconfined compressive and splitting tensile tests. Reverse injection is introduced to improve the uniformity of the calcium carbonate precipitation. The test results show that bo...
Article
Crushing of grains can greatly influence the strength, dilatancy, and stress-strain relationship of rockfill materials. The critical state line (CSL) in the void ratio versus mean effective stress plane was extended to the breakage critical state plane (BCSP). A state void-ratio-pressure index that incorporated the effect of grain crushing was prop...
Article
Several approaches have been developed to estimate the bearing capacity of aggregate pier reinforced clay, but these models exhibit large prediction bias and uncertainty. This study uses newly-developed footing loading test data to investigate the relationship between the bearing capacity and the area replacement and slenderness ratios. The bearing...
Article
Expanded polystyrene composite soil (EPSCS) has been used extensively in various engineering applications. However, the dynamic characteristics of EPSCS are not well understood. In order to understand the dynamic performance of EPSCS, a series of unconfined compression and resonant column tests were carried out to investigate its stiffness and damp...
Article
Full-text available
Deep foundations may be subjected to combined torsional and lateral loads. However, there are few full-scale observations to inform a complete understanding of the possible foundation response. This paper describes the generation and transfer of lateral loads that developed within drilled shaft foundations subjected to quasi-static and cyclic torsi...
Article
Full-text available
The effect of particle shape on the strength, dilatancy, and stress-dilatancy relationship was systematically investigated through a series of drained triaxial compression tests on sands mixed with angular and rounded glass beads of different proportions (0%, 25%, 50%, 75%, and 100%). A distinct overall regularity parameter was used to define the p...
Article
The effect of particle shape on the strength, dilatancy, and stress-dilatancy relationship was systematically investigated through a series of drained triaxial compression tests on sands mixed with angular and rounded glass beads of different proportions (0%, 25%, 50%, 75%, and 100%). A distinct overall regularity parameter was used to define the p...
Article
Deep foundations may need to resist torsional loads, resulting from wind loading on traffic sign and signal pole structures, or seismic loading on curved or skewed bridges. Although design methods for deep foundations at the ultimate limit states are readily available, no significant effort exists to quantify the accuracy of existing load transfer-...
Conference Paper
Full-text available
Deep foundations supporting skewed bridges and flyovers may need to resist torsional loads induced by seismic loading. To facilitate the serviceability and ultimate limit state design of a geometrically-variable deep foundation subjected to torsion in multi-layered soils, a software package, TorPILE, is developed using a finite difference model (FD...
Conference Paper
Significant densification can be achieved using driven displacement piles, which act to mitigate liquefaction through both densification and reinforcement. Recent research on driven displacement piles was used as a basis to offer an alternative to earthquake drains for the mitigation of liquefaction of a 4-story structure along coastal South Caroli...
Article
The prediction of liquefaction-induced damage to structures can be aided in part by an understanding of the magnitude of inherent spatial variability of the underlying liquefaction-susceptible soils. However, little is known about the role of clean sand and overburden stress correction of the cone penetration resistance on the magnitudes of the ran...
Article
Full-text available
Polyurethane foam adhesive (PFA), a product resulting from exothermic chemical polymerization reactions between the diisocyanate functional group and polyol monomers, can form a closed cellular structure with high strength and stiffness. In the current study, the effectiveness of PFA in improving the strength and ductility of a well-graded gravelly...
Article
Coral reefs and other calcareous deposits may experience various types of significant dynamic loading, such as those from waves and earthquakes. When submerged and subjected to earthquake loading, the potential for liquefaction of calcareous deposits may cause a loss of human life and property; however, few studies have evaluated the liquefaction p...
Article
The three-dimensional (3D) stress-strain response of uniform sands has been the focus of extensive laboratory investigations, resulting in well-established understanding of their 3D stress-strain-strength behavior. However, the applicability of stress-dilatancy theories and 3D stiffness, strength, and volumetric responses have not been sufficiently...
Article
The inherent spatial variability of natural soil deposits should be considered to obtain realistic probabilistically-based estimates of the time for soil consolidation. Although a variety of commercial software packages for solving consolidation analyses within numerical framework exist, they cannot incorporate spatial variability in a robust manne...
Article
Increasing awareness of the role of spatial variability in the assessment of liquefaction susceptibility has driven the need to characterize the vertical and horizontal spatial variability of liquefiable soils. Specifically, the variability of the standard penetration tests and cone penetration tests (CPTs) and the fines content are needed to evalu...
Article
Full-text available
The paper explores the possibility of estimating the horizontal scale of fluctuation (δ h) with limited CPTs. The following conditions are desirable: (a) the CPT depth is large; (b) there are more than two CPTs; (c) the CPT separation distances are distinct and preferably less than 2 × δ h; and (d) the Whittle-Matérn auto-correlation model is adopt...
Article
Steel casing is commonly used in drilled shaft construction to maintain the integrity of the borehole during drilling; however, little guidance regarding the effect of the casing on axial load transfer exists in the literature. To address this aspect of drilled shaft design and construction, this paper presents a study of axial load transfer of dri...
Article
Full-scale, controlled blasting field tests on driven displacement pile-improved ground were conducted to study the response of densified and reinforced ground to blast-induced excess pore pressures. In order to make appropriate comparisons to the baseline response of the native, unimproved ground, explosive charges sufficient to induce liquefactio...
Conference Paper
Increased understanding of the role of spatial variability of soils has spurred significant developments in the field of geotechnical engineering. Among these developments, recognition of the importance of lower bound capacity in reliability-based design appears to hold significant promise in improving the accuracy of probabilistic design procedure...
Conference Paper
Full-text available
The adoption of reliability-based design requires the selection of continuous probability distributions that adequately represent the uncertainty associated with a given random variable. Goodness-of-fit tests provide guidance towards selecting a distribution type; however, this approach does not give special consideration to the critical or control...
Conference Paper
Although soil is not deposited as a result of random processes, it is often convenient to treat the inherent variability within a given soil unit as a random field. Some reliability-based design codes require the adjustment of resistance factors within the LRFD framework based on site variability; however, there is a general lack of familiarity wit...
Conference Paper
Although our understanding of ground movements on structural damage has improved, the effect of inherent spatial variability of soil on the static and liquefaction-induced differential settlements of structures remains a challenge to the profession. Following a review of pertinent definitions and previous observations on structure performance in re...
Article
Full-text available
The use of augered cast-in-place (ACIP) piles for transportation infrastructure requires an appropriate reliability-based design (RBD) procedure. In an effort to improve the accuracy of an existing design model and calibrate appropriate resistance factors, this study presents a significantly revised RBD methodology for estimating the shaft and toe...
Article
Full-text available
This study proposes a reliability-based design procedure to evaluate the allowable load for augered cast-in-place (ACIP) piles installed in predominately granular soils based on a prescribed level of reliability at the serviceability limit state. The ultimate limit state (ULS) ACIP pile-specific design model proposed in the companion paper is incor...
Article
Full-text available
: Drilled shaft foundations commonly experience torsional loads, in addition to axial and lateral loading. Such cases include loads on mast arm traffic sign and signal poles, or seismically induced inertial loading of foundations supporting skewed or curved bridges. Despite the prevalence of drilled shafts, the understanding of the actual resistanc...
Article
In this study, resistance factors for the wave equation analysis of piles (WEAP) and a commonly used static analysis (SA) method are calibrated for use with piles driven in the Puget Sound Lowlands. Resistance factors are calibrated using a database of dynamic pile load test data with 95 piles monitored at the end-of-drive (EOD) condition and 94 pi...
Article
The installation sequence and spacing of displacement piles can influence the driving resistance (i.e., blow count) and associated capacity, however, engineers can rarely account for this effect in a direct manner. Increasing the availability of high-quality measurements of the effects of driving sequence and spacing to designers could help improve...