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This case study focuses on an International Circuit project in China where unmanned automobiles are to be tested in the future. The subgrade undergoes extensive settlement because of the widely distributed lacustrine deposits with high void ratio and compressibility. Prestressed high-strength concrete (PHC) pile-supported earth platforms are used for ground improvement in this area, but their effectiveness has not yet been confirmed. Associated with this adoption, the negative skin friction (NSF) of the piles and the related neutral plane (NP) position is of importance. Although NSF has been examined in detail, the NP position has not, especially with regard to its time dependence. This paper reports the settlement of the pile-supported soft soil subgrade as obtained from long-term observations of full-scale tests. The NP position is determined according to the layered settlement of the soil and the pile settlement, both of which are obtained from long-term field observations. The results reveal that the NP position has a clear time dependence that develops in stages. The NP is initially elevated with time, and then it gradually approaches a constant value. The existing models fail to predict this time dependence of the NP position in the studied sites. A exponential model is used, the fitting parameters of which have practical implications. The adopted model works well with the studied sites, especially in terms of reflecting the time dependence of the NP position and distinguishing the different stages of its development. This paper enhances the understanding of the NP and provides a reference data set for related engineering practices. [ABSTRACT FROM AUTHOR]

China National Offshore Oil Corporation (CNOOC) currently is developing a mat-supported wellhead production platform concept as an alternative solution to conventional jacket platforms in shallow-water oil fields. The platform is towed to the site with the mat foundation elevated. The mat then is lowered and embedded in the seabed as the hull is jacked out of the water. Steel pipe piles subsequently are driven through the tubular legs of the platform. After grouting the connection, the pile foundations provide permanent support for the platform. The mat foundation therefore provides only temporary support to the platform. This paper presents a case study focusing on the installation behavior of the mat foundation in a soft soil site as part of the platform concept development and suitability evaluation. The study determined (1) the expected penetration depth under the platform's self-weight considering its irregular geometry and soft over stiff clay stratigraphy; (2) the target center of gravity to achieve even penetration and the potential for tilt development in the case of offset from the target position; (3) the effectiveness of using ballast tanks to correct the tilt; and (4) settlement after the installation due to dissipation of pore pressure and creep. Advanced large-deformation finite-element simulations featuring a strain softening soil model and analytical analyses were performed. A dedicated lab testing program geared was designed and executed to provide the necessary soil parameters for the analyses. This paper presents the techniques and considerations that were applied in this study and insights gained into the installation and subsequent postinstallation behavior of large-area mat foundations. [ABSTRACT FROM AUTHOR]

During its service life, railway ballast degrades. Individual grains are abraded, asperities may break off, and the assembly loses performance as the finer material created progressively fouls the assembly. The causes of this are the repeated cyclic loading from passing trains and the major damage caused to ballast by tamping operations to restore track geometry. Eventually the ballast bed requires complete replacement, and recovered trackbed material is disposed of as waste or downcycled. However, modern ballasts often are formed from stronger parent rocks than in the past, and a proportion may retain sufficient characteristics for reuse. This paper investigated the reuse of recovered life-expired ballast. A series of tests using fresh and reused ballast was carried out using the Southampton Railway Testing Facility (SRTF) and a large triaxial testing apparatus to compare performance. The properties of individual ballast grains were characterized in terms of their shape and petrographic make up. The results show that the type of recovered life-expired ballast used in this study has good performance and similar strength to fresh ballast despite having reduced surface roughness. The petrographic analysis showed that a majority of the recovered ballast was formed of granite, with a significant minority of basalt. These findings may be in contrast to those of some previous studies in which different life-expired rock sources were used, and highlights the importance of the source material. [ABSTRACT FROM AUTHOR]

Estimation of nonlinear pile settlement can be simplified using one-dimensional " t-z " curves that conveniently divide the soil into multiple horizontal "slices." This simplification reduces the continuum analysis to a two-point boundary-value problem of the Winkler type, which can be tackled by standard numerical procedures. Theoretical " t-z " curves can be established using the "shearing-of-concentric-cylinders" theory of Cooke and Randolph-Wroth, which involves two main elements: (1) a constitutive model cast in flexibility form, γ=γ(τ) ; and (2) an attenuation function of shear stress with radial distance from the pile, τ=τ(r). Soil settlement can then be determined by integrating shear strains over the radial coordinate, which often leads to closed-form solutions. Despite the simplicity and physical appeal of the method, only a few theoretical " t-z " curves are available in the literature. This paper introduces three novel attenuation functions for shear stresses, inspired by continuum solutions, which are employed in conjunction with eight soil constitutive models leading to a set of 32 " t-z " curves. Illustrative examples of pile settlement calculation in two soil types are presented to demonstrate application of the method. [ABSTRACT FROM AUTHOR]

Expansion and contraction of an integral abutment bridge cause an abutment to move toward and away from its backfill due to seasonal temperature changes, thus causing high horizontal earth pressures behind the abutment and backfill surface settlements. This paper presents the results of four model tests conducted to simulate both translational and rotational movements of abutments and investigate horizontal earth pressures behind the abutment and the backfill surface settlements. The test results showed that the translational movement of the abutment likely prevented soil ratcheting from occurring in the upper portion of the backfill due to stress adjustments in the backfill after simulated seasonal temperature changes (i.e., causing limited earth pressure increase behind the abutment). Furthermore, the existing methods used to predict the horizontal earth pressures behind the abutment overestimated the pressures at the bottom of the abutment if the translational movement of the abutment was permitted. In addition, the backfill surface settlement near the abutment, induced by the seasonal temperature changes, was a function of footing rigidity and the displacement magnitude of the abutment and continued even after 30 cycles of abutment movement. [ABSTRACT FROM AUTHOR]

Schmertmann's method is one of the traditional methods for estimating the settlement of axially loaded footings in sand using cone penetration test (CPT) data. The method was developed for footings on a single, uniform sand layer; it assumes a depth of influence below the footing base within which most of the soil deformations take place and an influence diagram to quantify the influence factor as a function of depth. However, the literature contains limited information on the strain influence diagrams for footings on layered sands, and, as a result, there is no way to accurately account for the effect of sand layering on footing settlement. In this paper, Schmertmann's approach for calculating the strain influence factor is modified to account for the effect of two sand layers with varying thickness and relative density. Penetration experiments were performed using a half-square model footing (width B=90 mm) placed on the surface of both single and two-layered (dense over medium-dense and medium-dense over dense), air-pluviated silica sand samples prepared inside a half-cylindrical calibration chamber designed for digital image correlation (DIC) analysis. The test results indicate that both the thickness and relative density of the top sand layer (the layer in contact with the footing base) affect the parameters of the strain influence diagram. For dense sand over medium-dense sand, the depth to the peak strain influence factor varies with the thickness of the dense layer; however, when the thickness of the dense layer is 1.5B or greater, the strain influence diagram is similar to that obtained for a single, uniform sand layer. In contrast, for medium-dense sand over dense sand, the peak value of the strain influence factor varies with the thickness of the medium-dense layer up to a value of 1B. Based on the results obtained in this study, new strain influence diagrams are proposed for settlement calculation of square footings on two-layered sand profiles. The proposed method for estimation of footing settlement in layered sand is validated against measured data obtained from a full-scale, instrumented footing load test reported in the literature. [ABSTRACT FROM AUTHOR]

In this paper, we present a probabilistic predictive procedure for a foundation's permanent average settlement on liquefiable soils improved with ground densification. The proposed procedure is based on 770 three-dimensional (3D), fully coupled, effective-stress, finite-element analyses designed through quasi-Monte Carlo sampling of key input parameters. The numerical models are themselves calibrated and validated with centrifuge model studies, and they consider realistic, nonlinear, 3D structures on shallow foundations, seismic soil–structure interaction, interlayering and layer cross interactions, ground densification properties and geometry, and ground motion characteristics. We use nonlinear regression with lasso-type regularization to estimate model coefficients. The primary predictors of a foundation's settlement are identified as the cumulative absolute velocity of the outcropping rock motion; total thickness of the soil deposit above bedrock and cumulative thickness of the critical liquefiable layer(s); the foundation's bearing pressure, size, and embedment depth; the structure's total height; the achieved density and size of ground improvement; and the thickness of the remaining undensified susceptible soils within the foundation's influence zone. In the end, the predictive model is shown to capture the trends in a limited number of centrifuge and field case histories collected from the literature. The insight from the numerical database and the first-of-its-kind predictive model aims to guide the design of liquefaction mitigation strategies that improve the performance of the soil–foundation–structure system holistically and reliably. [ABSTRACT FROM AUTHOR]

This paper presents an empirical methodology that allows calculation of ground displacements behind corners of retained cut excavations. The increased stiffness of a retaining wall at the corner of an excavation normally leads to a corresponding reduction in ground movements behind the retaining wall. These 'corner effects' derived from retained cut excavations can only be assessed at present by using three-dimensional numerical analysis or empirical methods. Significant cost and time can be taken carrying out three dimensional analysis, which, additionally, is not normally carried out at an early stage of the design of a project. Furthermore, numerical analysis must be undertaken by a competent person with appropriate training. An inappropriate analysis can yield to misleading and counterproductive results. This constitutes an expensive requirement on practitioners that often resort to more conservative designs which ignore corner effects. The methodology of adjusting calculated ground movements around corners of excavations described in this paper is simple to use and easy to program into software or spreadsheets. It can be used in conjunction with two-dimensional numerical analysis and also for calculating displacements in early stages of projects when numerical analysis has not yet been undertaken. This allows for more informed early discussion with third parties where approvals are sought on a given project. [ABSTRACT FROM AUTHOR]

Although there are many methods for assessing vertical stiffness of footings on the ground, simplified solutions to evaluate lateral, rotational, and torsional static stiffness are much more limited, particularly for nonhomogeneous profiles of shear modulus with depth. This paper addresses the topic by introducing a novel "work-equivalent" framework to develop new simplified design methods for estimating the stiffnesses of footings under multiple degrees-of-freedom loading for general nonhomogeneous soils. Furthermore, this framework provides a unified basis to analyze two existing design methods that have diverging results. 3D finite element analyses were carried out to investigate the soil–footing interaction for a range of continuously varying and multilayered nonhomogeneous soils, and to validate the new design approach. [ABSTRACT FROM AUTHOR]

This paper investigates the efficacy of recycled-plastic pins (RPPs) for controlling the ground settlement of soft foundation soil. Two field test sections (6×7.5 m) were constructed over soft soil; one was left unreinforced to use it as a control section, and the other section was reinforced with RPPs. A load transfer platform (LTP), composed of recycled crushed concrete aggregate (RCCA), sandwiched between two geogrid layers, was placed above the RPPs for transferring the load from the embankment onto the RPPs. Vertical pressures, settlements, and pore water pressures were monitored. After 260 days, a maximum settlement of 52 mm was observed for the control section, whereas for the reinforced section, it was 23 mm. Excess pore pressure dissipated faster in the control section. The measured data indicated that the RPPs supported a significant percentage of the embankment load. The in-situ measurements have proven the effectiveness of RPPs in combination with LTP in reducing settlement. The present method can be applied for any embankment construction over soft soil, bridge approaches, and widening of a highway where the foundation soil is unsuitable for regular construction. [ABSTRACT FROM AUTHOR]

The significant damage observed during recent earthquakes resulting from liquefaction of shallow saturated soil deposits beneath structures has illustrated the need for further research in the area of liquefaction-induced ground movement effects. This study used the shake table facility at the University of California, San Diego to evaluate the liquefaction-induced settlement of a shallow foundation founded on top of liquefiable ground conditions. To study the seismic performance of a shallow rigid foundation, two large-scale shake table tests were conducted using different input motions with varying peak accelerations. The experimental model comprised three soil layers and included a shallow foundation seated over an unsaturated crust layer underlain by saturated loose and dense layers. The model ground was based on similar subsurface ground conditions observed in recent earthquakes in New Zealand, Japan, and Turkey. The seismic response of the model foundation and the soil was captured through intensive instrumentation. The main purpose of this study was to better understand the contributing mechanisms in liquefaction-induced settlement of buildings during strong shaking. Results from this series of tests were used to explore different liquefaction mitigation countermeasures; this study served as a baseline for two follow-on shake table tests which are not discussed in this paper. Detailed discussions of the excess pore-water pressure generation and dissipation, and its effect on the contributing mechanisms of liquefaction-induced settlement are presented, along with the application of standardized cumulative absolute velocity as an intensity measure to estimate the amount of liquefaction-induced settlement. The flow velocity calculation due to hydraulic transient gradient indicated an upward flow in the loose layer, which explains the observed sand ejecta. Measured and estimated foundation settlements were compared using simplified procedures. The observed foundation settlement generally was higher than the estimated settlement. This series of large-scale shake table tests provides a unique benchmark for calibration of numerical models, and simplified procedures to reliably estimate liquefaction-induced building settlements. Future mitigation tests can be evaluated using the results of this baseline experimental study. [ABSTRACT FROM AUTHOR]

Equations are derived to calculate one-dimensional (vertical) consolidation settlement in aquifers caused by groundwater extraction. The settlement equations capture the effect that the decline in pore-water pressure caused by groundwater extraction has on increased vertical effective stress. The settlement equations for single-layered confined or unconfined aquifers and multiple-layered aquifers are derived by linking the increase in vertical effective stress to the reduction of the void ratio using the reconstructed field consolidation curve of aquifer sediments. This paper's approach blends groundwater hydraulics with the classical theory of one-dimensional consolidation widely used in geotechnical engineering. Closed-form consolidation settlement equations are presented for single-layer, homogeneous, isotropic confined aquifers with steady-state or transient groundwater flow and for single-layer, homogeneous, isotropic, unconfined aquifers under steady-state flow. The consolidation equations for consolidated settlement in heterogeneous, anisotropic, single-layer or multilayer aquifers are expressed as the numerical integration of the vertical strain induced by groundwater pumping. The numerical-integration settlement equations require the implementation of a groundwater simulation model to calculate the pore pressure decline within aquifer layers, followed by the calculation of the increase in vertical effective stress and the reduction in pore volume. One numerical example confirms the accuracy of this paper's approach to aquifer consolidation by comparing with the solution obtained with the three-dimensional poroelastic theory. [ABSTRACT FROM AUTHOR]

This paper presents the practical elastic settlement formulae for the eccentrically loaded surface footings resting upon an elastic mass. The presented closed-form solutions can be readily implemented into the practice allowing efficient and accurate prediction of elastic settlement under the rectangular footing which is subjected to the biaxial bending. The presented solutions are determined by evaluating the integration of strain expressions based on the Boussinesq stress equations. The common assumption of linear contact pressure in footing-soil interface is adopted for the solutions. The presented formulae are validated to be used for the settlement under any point of linear full-contact loading and their applicability to the current design process is demonstrated. The solutions are also developed for the theoretical cases where the location of incompressible soil layer is infinitely deep. The simplified influence factors are presented graphically and the numerical examples are provided for their practical use. In this respect, the paper represents a significant step forward in understanding of elastic settlement, rotation, and differential elastic settlement under eccentrically loaded footings. [ABSTRACT FROM AUTHOR]

In this paper, the excavation-induced settlement determined by the KJHH model, a recently developed semiempirical model, is used to assess the serviceability reliability of adjacent buildings. The calculated settlement, considered as the load in the context of reliability analyses in this paper, is compared with a tolerable settlement, considered as the resistance herein. The reliability of the adjacent building against “damage” (defined herein as the violation of serviceability requirements such as having intolerable settlement) is first analyzed and the probability of exceedance (i.e., exceeding the tolerable settlement) is calculated. Furthermore, as the excavation proceeds, observed settlement at the current excavation stage is used to update the prediction of settlement at subsequent stages, and the probability of exceedance is updated accordingly. [ABSTRACT FROM AUTHOR]

This paper is the second of a two-part series describing an investigation of the mechanical behavior of rammed aggregate piers in supporting rigid square footings. In this paper, the performances of two pier-supported footings and three isolated piers during compressive load tests were simulated using an axisymmetric finite element model and compared to experimental data. A hardening-soil constitutive model with parameters estimated from in situ and laboratory tests was used to characterize the constitutive behaviors of the pier material and the matrix soil. Pier groups were modeled as unit cells with the tributary area determined from the center-to-center spacing. Cavity expansion modeling was used to simulate the pier installation process. Verifications of the numerical model were carried out by comparing the numerical results with the data obtained from full-scale, instrumented load tests. Interpretation of the numerical results focused on the load-deformation behavior, group effect, stress concentration ratio, and the development of stresses in the matrix soil. The distributions of vertical stress underneath the pier-supported footings are also characterized. [ABSTRACT FROM AUTHOR]

Deep excavations may cause settlement and damage to adjacent buildings, even if they are found on piles. The corresponding pile deformations are determined by axial and lateral effects. This paper describes an analytical model relating axial pile deformation to the vertical soil displacement resulting from the deep excavation and also suggests ways to determine the pile response to lateral displacements. The axial pile-soil interaction is clearly different for end-bearing and friction piles. Common generalizations that end-bearing piles settle the same as the soil settlement at the base level and friction piles with the ground surface settlement present lower and upper bounds, which are only valid for certain idealized cases. The settlement of piles with a large component of shaft friction is determined mainly by the actual load on the pile relative to the pile ultimate capacity. The lateral pile response is governed mainly by the relative stiffness of the pile to the soil. The proposed model was validated with measurements of the North South Line project in Amsterdam. [ABSTRACT FROM AUTHOR]

The effective mitigation of the liquefaction hazard requires an improved understanding of the consequences of liquefaction in terms of ground shaking, permanent displacement, and building performance. In this paper, results from centrifuge experiments of a shallow-founded structure on liquefiable sand are used to evaluate the predictive capabilities of a state-of-the-art numerical tool. Solid-fluid, fully-coupled 3D nonlinear numerical simulations were performed using the PDMY02 soil model implemented in a software modeling domain. The numerical model captured excess pore pressures and accelerations well in the free-field, but largely underestimated volumetric settlements due to loss of water during shaking. This was associated with the drastic increase in soil hydraulic conductivity when approaching liquefaction, which was not taken into account numerically, as well as the underestimation of soil volumetric compressibility. The contribution of volumetric strains to total building settlement was, however, relatively minor. Hence, by capturing the excess pore pressures and accelerations under the foundation, the model could capture deviatoric displacements and hence building's settlement and tilt response. The results of the experiments and numerical simulations are combined in this paper to provide guidance on the evaluation of building response on liquefiable ground. [ABSTRACT FROM AUTHOR]

The legal limitations on the amount of biodegradable municipal solid waste (MSW) disposed of to landfill have led to the development of a range of pretreatment processes known generically as mechanical biological treatment (MBT). This paper presents the results of a detailed study of the degradation and settlement characteristics of two such MBT waste residues. The effects of mechanical creep and biodegradation are quantified separately, and compared with each other and with those for raw (untreated) MSW. The effects of different degrees of treatment prior to landfilling are considered in the context of the relationship between biodegradation and settlement. The results are discussed with reference to uncoupled models for estimating consolidation, creep, and biodegradation-induced settlements in MBT wastes. The methods for determining appropriate parameter values and applying these models to practice are also suggested. [ABSTRACT FROM AUTHOR]

An evaluation of scale effects, stress, waste segregation, and waste decomposition on the immediate compression behavior of municipal solid waste is presented. Laboratory experiments were conducted in 64-, 100-, and 305-mm-diameter compression cells. A field-scale experiment [Deer Track Bioreactor Experiment (DTBE)] was conducted on waste of the same composition and material properties. A methodology is presented for determining the end-of-immediate compression strain ( ɛEOI) that is applicable to both laboratory- and field-scale data. The compression ratio () was comparable between tests conducted in 100- and 305-mm compression cells. Compression tests in 305-mm cells conducted on six wastes (three size-differentiated fresh wastes and three decomposed wastes) yielded ranging from 0.22 to 0.28 in the stress range of 25-100 kPa. A similar (0.23) was determined for the DTBE (20-67 kPa). The variation in is related to the waste compressibility index (WCI), which is a function of waste dry weight water content, dry unit weight, and the percent contribution of biodegradable organic waste (paper/cardboard, food waste, yard waste). A compilation of laboratory data from this study and the literature yielded a predictive relationship for the and WCI. The can be estimated within ±0.087 for a given WCI using this relationship. [ABSTRACT FROM AUTHOR]

Piled raft foundations are often used when the supporting soil has adequate bearing capacity but the raft settlements exceed allowable values. In traditional practice, long piles with high load capacity are usually used that may lead to two structural problems: the structural collapse of the pile and large strains mobilized in the raft leading to an uneconomic design. This paper presents an experimental study of the effectiveness of using short piles either connected or unconnected to the raft (instead of long piles) on the behavior of an eccentrically loaded raft. The load configuration was designed to simulate rafts under vertical loads and overturning moment. Several arrangements of piles with different lengths and numbers along with the effect of the relative density of the soil and the load eccentricity were studied. Test results indicate that the inclusion of short piles adjacent to the raft edges not only significantly improves the raft bearing pressures but also leads to a reduction in raft settlements and tilts leading to an economical design of the raft. However, the efficiency of the short piles-raft system is dependent on the load eccentricity ratio and pile arrangement. Also, connecting short piles to the raft gives greater improvement in the raft behavior than unconnected piles. Based on test results, the effects of different parameters are presented and discussed. [ABSTRACT FROM AUTHOR]

This paper presents centrifuge data from model footing tests on dry sand, where a high resolution optical displacement measurement technique was employed to record subsurface soil displacements beneath the centerline of loaded strip footings. These measurements allow derivation of vertical strain profiles, which are then used to estimate operational soil stiffness values. The stiffness values, which were assessed assuming a dependence on cone penetration test tip resistance and initial vertical effective stress level, are shown to degrade rapidly with increasing strain level. Despite such nonlinearity, the experimental strain data can be represented using an updated form of the well known Schmertmann strain influence profile. Settlements calculated using this profile are shown to be in agreement with subsurface settlements when appropriate soil stiffness values are employed. [ABSTRACT FROM AUTHOR]

This paper presents a simplified model for evaluating damage potential of a building adjacent to a braced excavation. New developments include several component models for estimating the lateral ground movement profile, angular distortion and lateral strain in a building, and damage potential of a building adjacent to an excavation. These new developments along with an existing model for the vertical ground movement profile are integrated into the proposed simplified model. Case histories are used to verify the developed simplified model. Furthermore, the uncertainty in the developed model is quantified, which enables a probabilistic assessment of the excavation-induced building damage potential. An example probabilistic assessment of building damage potential is presented. [ABSTRACT FROM AUTHOR]

Current design guidelines for shallow foundations supporting building and bridge structures discourage footing rocking or sliding during seismic loading. Recent research indicates that footing rocking has the potential to reduce ductility demands on structures by dissipating earthquake energy at the footing-soil interface. Concerns over cyclic and permanent displacements of the foundation during rocking and sliding along with the dependence of foundation capacity on uncertain soil properties hinder the use of footing rocking in practice. This paper presents the findings of a series of centrifuge experiments conducted on shear wall-footing structures supported by dry dense to medium dense sand foundations that are subjected to lateral cyclic loading. Two key parameters, static vertical factor of safety (FSV), and the applied normalized moment-to-shear ratio (M/(H·L)) at the footing-soil interface, along with other parameters, were varied systematically and the effects of these parameters on footing-soil system behavior are presented. As expected, the ratio of moment to the horizontal load affects the relative magnitude of rotational and sliding displacement of the footing. Results also show that, for a particular FSV, footings with a large moment to shear ratio dissipate considerably more energy through rocking and suffer less permanent settlement than footings with a low moment to shear ratio. The ratio of actual footing area (A) to the area required to support the vertical and shear loads (Ac), called the critical contact area ratio (A/Ac), is used to correlate results from tests with different moment to shear ratio. It is found that footings with similar A/Ac display similar relationships between cyclic moment-rotation and cumulative settlement, irrespective of the moment-to-shear ratio. It is suggested that shallow foundations with a sufficiently large A/Ac suffer small permanent settlements and have a well defined moment capacity; hence they may be used as effective energy dissipation devices that limit loads transmitted to the superstructure. [ABSTRACT FROM AUTHOR]

A maximum likelihood framework for the probabilistic assessment of cyclically induced reconsolidation settlements of saturated cohesionless soil sites is described. For this purpose, over 200 case history sites were carefully studied. After screening for data quality and completeness, the resulting database is composed of 49 high-quality, cyclically induced ground settlement case histories from seven different earthquakes. For these case history sites, settlement predictions by currently available methods of Tokimatsu and Seed (1984), Ishihara and Yoshimine (1992), Shamoto et al. (1998), and Wu and Seed (2004) are presented comparatively, along with the predictions of the proposed probabilistic model. As an integral part of the proposed model, the volumetric strain correlation presented in the companion paper is used. The accuracy of the mean predictions as well as their uncertainty is assessed by both linear regression and maximum likelihood methodologies. The analyses results revealed that (1) the predictions of Shamoto et al. and Tokimatsu and Seed are smaller than the actual settlements and need to be calibrated by a factor of 1.93 and 1.45, respectively; and (2) Ishihara and Yoshimine, and Wu and Seed predictions are higher than the actual settlements and need to be calibrated by a factor of 0.90 and 0.98, respectively. The Wu and Seed procedure produced the most unbiased estimates of mean settlements [i.e., their calibration coefficient (0.98) is the closest to unity], but the uncertainty (scatter) of their predictions remains high as revealed by the second to last smaller R2 value, or relatively higher standard deviation (σ[variant_greek_epsilon]) of the model error. In addition to superior model predictions, the main advantage of the proposed methodology is the probabilistic nature of the calibration scheme, which enables incorporation of the model uncertainty into mean settlement predictions. To illustrate the potential use of the proposed model, the probability of cyclically induced reconsolidation settlement of a site after a scenario earthquake to be less than a threshold settlement level is assessed. [ABSTRACT FROM AUTHOR]

Most of the existing methods for estimating settlements of footings in sand have been developed for either isolated square footings or for strip footings. The literature contains limited information on settlement analysis of rectangular footings, and, as a result, there is no way to accurately account for the effect of the footing length-to-width ratio on settlement. Additionally, no practical method exists for considering the interaction between neighboring footings in settlement estimates. In this paper, we use Schmertmann’s framework to propose a method of settlement estimation that takes full account of both the footing length-to-width ratio and the proximity of neighboring footings. Three-dimensional nonlinear finite element analyses were performed for various multiple footing configurations. Plate load tests were performed in sands using both a single plate and two plates separated by various distances. The numerical and experimental results indicate that the shape of the footing (expressed through its length-to-width ratio) and the proximity of neighboring footings affect two parameters of the strain influence diagram (which is the basis for the settlement estimation method): the depth to the peak influence factor Izp and the depth of the strain influence zone. We propose new strain influence diagrams for estimation of settlement under these more general conditions. [ABSTRACT FROM AUTHOR]

Accurate prediction of ground-surface settlement adjacent to an excavation is often difficult to achieve without using accurate representation of small-strain nonlinearity in a soil model within finite-element analyses. In this paper a simplified semiempirical model is proposed for predicting maximum wall deflection, maximum surface settlement, and surface-settlement profile due to excavations in soft to medium clays. A large number of artificial data are generated through finite-element analyses using a well-calibrated, small-strain soil model. These data, consisting of wall displacements and ground-surface settlements in simulated excavations in soft to medium clays, provide the basis for developing the proposed semiempirical model. The proposed model is verified using case histories not used in the development of the model. The study shows that the developed model can accurately predict maximum wall deflection and ground-surface settlement caused by braced excavations in soft to medium clays. [ABSTRACT FROM AUTHOR]

Assessment of earthquake-induced liquefaction is an important topic in geotechnical engineering due to the significant potential for damage to infrastructure. Some of the most significant infrastructure damage occurs due to differential settlement of the ground, including due to liquefaction. Postliquefaction deformations commonly are assessed using one-dimensional empirical models, which inherently assume laterally homogeneous soil layers. Numerical models offer the potential to examine the effects of ground motion variability and spatially variable soil properties on liquefaction-induced deformations. This study explored the postliquefaction reconsolidation settlement for a site in Hollywood, South Carolina, which was characterized using a three-dimensional (3D) geostatistical model and simulated using the numerical platform FLAC and constitutive model PM4Sand. The effects of ground motion characteristics on mean and maximum differential settlements were investigated. The physical mechanisms associated with postliquefaction responses such as excess pore pressures, shear strains, and volumetric strains also were examined. The efficacy of uniform models assuming representative percentile soil properties to represent the stochastic mean settlement was investigated. The inherent inability of uniform models to capture differential settlements and therefore the need for using stochastic models is discussed. [ABSTRACT FROM AUTHOR]

The inclusion of granular columns in soft clay deposits leads to improvements in bearing capacity and overall stiffness, along with a reduction in consolidation settlement. Many laboratory investigations have focused on aspects of bearing capacity, but published data on settlement performance are limited. This paper reports on some interesting findings obtained from a laboratory model study with respect to these issues. In this investigation, 300 mm diameter by 400 mm long samples of soft kaolin clay were reinforced with single or multiple granular columns of various lengths using the displacement and replacement installation methods. The experimental findings revealed that, for the same area replacement ratio, limited settlement reduction was achieved for single long floating columns and end-bearing column groups. Marginal improvements in settlement performance were also achieved for columns installed by the displacement method. No settlement reduction was achieved for short single floating columns, whereas short floating granular column groups produced increased settlements. These observations were verified using contact pressure measurements between the footing and column/surrounding clay. [ABSTRACT FROM AUTHOR]

The effective design of earthquake-resistant structures and liquefaction mitigation techniques requires an improved understanding of the development and consequences of liquefaction. In this paper, the results from centrifuge experiments of structures with shallow foundations on liquefiable sand were used to evaluate the predictive capabilities of a state-of-the-practice numerical tool. Fully-coupled numerical simulations with the UBCSAND model implemented in FLAC-2D captured building settlements measured in these experiments reasonably well for one scaled input motion, mostly within factors of 0.7 and 1.8. The soil model captured the overall contribution of deviatoric displacement mechanisms and localized volumetric strains during partially drained cyclic loading. The primary limitation of the model became evident for slower rates of earthquake energy buildup, when the extent of soil softening and building displacement was overestimated by up to a factor of 4. The observations from recent case histories, the results of the experiments, and the insights gained from the numerical analyses are combined to provide guidance on the evaluation of building response on liquefiable sand and the performance of liquefaction remediation strategies. [ABSTRACT FROM AUTHOR]

Underground tunneling, besides raising geotechnical challenges, can often modify the hydrological regime around an excavated area. This fact entails not only the modification of superficial aquifers but also the appearance of subsidence phenomena as a consequence of the decrease in pore pressure. In the end, this may jeopardize the structural integrity of the construction, leading to delays and undesirable secondary effects. This paper documents the problems arising from the construction of a railway tunnel for a high-speed train in the province of Orense in the northwest of Spain. The tunnel was excavated through a highly weathered granitic massif using conventional methods. The drawdown in the water table caused by the tunnel advance was analyzed and monitored. The initial lowering of the water level was followed by a period of soil subsidence with deflections reaching up to 104 mm. These differential settlements happened along a 150-m strip on both sides of the tunnel axes, which affected urbanized areas. The topographic downfall was located ahead of the perforation head; however, it occurred after the lowering of the water table as an immediate consequence. [ABSTRACT FROM AUTHOR]

Skirted gravity base foundations and suction caisson foundations are considered as viable alternatives to monopile foundations for offshore wind turbines. While recent work has focused on the monotonic moment-rotation response for shallow foundations, the cyclic response and the accumulation of rotation over the life of the turbine must also be addressed. This paper presents cyclic loading tests where approximately 10,000 cycles, with different loading characteristics, were applied to a model shallow foundation (a caisson) in loose sand. On the basis of these tests, a framework for assessing the accumulated angular rotation because of cycling was developed. The settlement and cyclic stiffness response of the caisson were also assessed. It was found, not unexpectedly, that the accumulated settlement of the caisson increased with the number of cycles and cyclic amplitude. It was also found that a cyclic loading regime intermediate between one-way and full two-way cycling produced the largest rotations. The cyclic stiffness was relatively unaffected by the number of cycles. Using an appropriate scaling technique, the proposed framework was used to predict the long-term accumulated angular rotation, for an example, the field-scale monocaisson structure. [ABSTRACT FROM AUTHOR]

In geotechnical engineering, recycled tires are used in lightweight fills, backfill materials, highway embankments, soil reinforcement, and soil-retaining walls. The rubber-soil mixture can exhibit a greater capacity for energy absorbency than soil alone under cyclic loading and tends to decrease the stress and shocks transferred into the ground. The shear strength and energy absorbance of the rubber-soil mixture is highly dependent on the size of the rubber fragments and the proportion in the soil. In this paper, soil surface settlement, pipe deflection, and pressure distributed over a pipe placed in a trench and subject to cyclic loading were investigated as a function of chipped and shredded rubber used as backfill. The observed responses show that the shredded rubber-soil mixture used over the pipe is more effective in reducing these three parameters when covered by a soil cap, than when using the same soil alone for the whole of the fill. Also, using the rubber-soil mixture in the whole of backfill without a soil cap delivers a negative influence on the responses. Overall, shredded rubber has a better performance in regards to the pipe responses than the chipped rubber. By using a soil cap over the rubber-soil mixture, the reduction in the subsequent soil settlement and plastic pipe deflection, attenuation of the pipe's accumulating strains, and finally protection of the buried pipe from fatigue are achievable. [ABSTRACT FROM AUTHOR]

Buildings founded in proximity to shallow tunnels under construction may be damaged by the ground displacements induced by tunneling. This is a matter of concern for design, and a variety of protective interventions are currently adopted to prevent such damages. Among these, rows of piles or jet-grouting columns are widely diffused. In this paper, the effectiveness of a simple row of piles is computed by means of three-dimensional (3D) finite-element (FE) analyses, thus allowing the investigation of the relationship between performance and some simple geometrical parameters, such as the spacing among the piles. The results of centrifuge tests are reported and used as a benchmark. The potential damage has been quantified in this work, taking into account both the settlement profile and the horizontal strain induced at the ground surface by tunneling. It is shown that although the settlement reduction is significant only for very small spacing (s=2-3 pile diameters), even largely spaced piles (s=5-6 pile diameters) are useful to prevent damage to buildings because of the significant reduction of the average horizontal strain. [ABSTRACT FROM AUTHOR]

When designing embankments over soft soils, geotechnical engineers face many challenges. These include potential bearing failure, intolerable settlement, and global or local instability. Pile-supported embankments have been emerged as an effective alternative successfully adopted worldwide to solve these problems. This paper focuses on three cases in which pile-supported embankments were used for constructing highways in the eastern coastal region of China. Each case provides a description of the soil profile, construction procedure, and field monitoring of the settlements, earth pressures, and pore-water pressures. Field monitored data from contact pressures acting on the piles and the soils, to the settlements of the piles and the soils are reported and discussed. The development of the earth pressures both on the piles and the soils shows that there was a significant soil arching in the embankment, and the measured earth pressures acting on the piles are much higher than that acting on the soils between the piles. The measured differential settlements between the piles and the soils are small. The pore-water pressures are not significant compared to the embankment loads. Most pore-water pressure dissipated after the complete of filling. The measurements have proven the effectiveness of this technique in reducing total and differential settlements. Finally, the available design standards and approaches are verified by three cases. [ABSTRACT FROM AUTHOR]

The estimation of the capacity and settlement of landfills is critical to successful site operation and future development of a landfill. This paper reports the results of a study on biodegradation behavior and the compression of municipal solid wastes. An experimental apparatus was developed which had a temperature-control system, a leachate recycling system, a loading system, and a gas and liquid collection system. Experiments were performed both with and without optimal biodegradation for comparative purposes. Test results indicated that settlement resulting from creep was relatively insignificant when the biodegradation process was inhibited. Compression due to decomposition under optimal biodegradation conditions was found to be much larger than compression associated with creep. The biodegradation process was significantly influenced by the operational temperature. A one-dimensional model is proposed for calculating settlement and estimating the capacity of the landfill under relatively optimal biodegradation conditions. The model was developed to accommodate the calculation of settlement in landfills when a multistep filling procedure was used. The calculation method is relatively simple and convenient for design purposes. Simulations of the physical processes showed that enhancing solid waste biodegradation during the filling stage can considerably increase the capacity of the landfill and reduce postclosure settlements. [ABSTRACT FROM AUTHOR]

In 2001, the Utah Department of Transportation completed a 4-year $1.4 billion I-15 reconstruction project in Salt Lake City, Utah. This project included widespread use of expanded polystyrene geofoam as lightweight embankment at important utility crossings and where close proximity to existing buildings necessitated minimizing consolidation settlement. This paper presents construction and long-term monitoring results for some of these embankments with numerical modeling of the field measurements. Fast Lagrangian Analysis of Continua, a finite-difference program, was used to estimate the complex stress distribution and the displacements (i.e., strain) that developed in select geofoam embankments. The writers used a bilinear elastic model to produce reasonable estimates of gap closure, block seating, and the subsequent elastic compression of the geofoam embankment at higher stress levels. Such estimations are important for modeling and designing geofoam embankments and potential connections with other systems. The calculation of the complex stress distribution and displacements that develops in a geofoam embankment has application to settlement, lateral earth pressure against retaining and buried walls, slope stability, and seismic design of geofoam embankments. [ABSTRACT FROM AUTHOR]

Tapered piles in comparison to cylindrical piles can be beneficial in terms of the load capacity. In this paper, estimation of the load capacity for tapered piles using cone penetration test (CPT) resistance was investigated. Fourteen calibration chamber load tests using different pile types and six CPTs were conducted under various soil conditions. From the calibration chamber test results, the total, base, and shaft load capacities were analyzed in terms of soil conditions and taper angle. To evaluate CPT-based load capacity of tapered piles, normalized base and shaft resistances were obtained from normalized unit load-settlement curves. Based on the normalized base and shaft resistances, design equations that can be used to evaluate the base and shaft resistances of tapered piles were proposed. The proposed method is valid for sands of medium to dense conditions, while it may result in unconservative predictions for loose sands. To check the accuracy of the proposed method, field load tests using both cylindrical and tapered piles were conducted and compared with the predictions using the proposed method. A simplified approach using an equivalent cylindrical pile was also investigated and compared. [ABSTRACT FROM AUTHOR]

A probabilistic analysis of a shallow circular tunnel driven by a pressurized shield in a frictional and/or cohesive soil is presented. Both the ultimate limit state (ULS) and serviceability limit state (SLS) are considered in the analysis. Two deterministic models based on numerical simulations are used. The first one computes the tunnel collapse pressure and the second one calculates the maximal settlement due to the applied face pressure. The response surface methodology is utilized for the assessment of the Hasofer-Lind reliability index for both limit states. Only the soil shear strength parameters are considered as random variables while studying the ULS. However, for the SLS, both the shear strength parameters and Young’s modulus of the soil are considered as random variables. For ULS, the assumption of uncorrelated variables was found conservative in comparison to the one of negatively correlated parameters. For both ULS and SLS, the assumption of nonnormal distribution for the random variables has almost no effect on the reliability index for the practical range of values of the applied pressure. Finally, it was found that the system reliability depends on both limit states. Notice however that the contribution of ULS to the system reliability was not significant. Thus, SLS can be used alone for the assessment of the tunnel reliability. [ABSTRACT FROM AUTHOR]

Traditionally, analyses developed for circular piles have also been used for rectangular piles by replacing in calculations the rectangular pile with a circular pile of equivalent area. In this paper, we present a settlement analysis that applies to piles with either rectangular or circular cross sections installed in multilayered soil deposits. The analysis follows from the solution of the differential equations governing the displacements of the pile-soil system obtained using variational principles. The input parameters needed for the analysis are the pile geometry and the elastic constants of the soil and pile. Pile displacements and vertical soil displacements calculated using this analysis match well those from finite-element analysis. A parametric study highlights some important insights for rectangular and circular piles in multilayered soil. A user-friendly spreadsheet program (ALPAXL) was developed to facilitate the use of the analysis. Examples illustrate the use of the analysis in design. [ABSTRACT FROM AUTHOR]

This paper describes the development and application of design charts for piled embankment designs. It outlines the computational approach adopted, the geotechnical profiles used, and the application of the design procedure using the charts. The soil profile used for the charts is representative of a Malaysian soft clay profile, involving a more or less normally consolidated soil, with a strength and stiffness that varies linearly with depth. Such a profile is typical of the ground conditions in a variety of countries in the Southeast Asian region. The design charts address the issues of pile capacity, settlement due to embankment load, settlement due to a temporary piling construction platform, and lateral response of piles near the edge of the embankment. The charts consider variations in ground conditions, embankment height, pile length, and pile spacing. An illustrative example is given to demonstrate the use of the charts. [ABSTRACT FROM AUTHOR]

This paper examines immediate and time-dependent compression of tire derived aggregate (TDA) and TDA-soil composites. To accommodate large particle sizes, modified experimental devices were developed and used to test tire chips and tire shreds. Immediate compression of TDA, which results almost entirely from the reduction of pore volume, increases with TDA content and tire particle size. The secant constrained modulus (Msec) of TDA defined over the stress range of 0–50 kPa varied from a low of 255 kPa (100% tire shreds) to a high of 1,320 kPa (50% tire chips). A characteristic relationship between strain and time exists for TDA and TDA composites under one-dimensional confined compression. Time-dependent deformation is well described by the modified secondary compression index (Cα[variant_greek_epsilon]), which ranged from 0.0010 (50% tire chips) to 0.0074 (100% tire chips). Time-dependent deformation was inversely proportional to sand content, with the most significant changes resulting from the addition of 15% sand. Both applied stress and tire particle size appear to have a negligible effect on time-dependent compression of TDA. Based on the findings of this study it is recommended that practitioners assess time-dependent settlement when designing a TDA structure and if necessary incorporate design features to accommodate these settlements. [ABSTRACT FROM AUTHOR]

Constructing concrete-faced rockfill dams (CFRDs) with weak rocks has great advantages as a result of the use of local materials, cost-effectiveness, extensive adaptability, simple construction, and short construction period. However, the behaviors of CFRDs constructed with weak rocks are not well-understood. This paper reports the physical, mechanical, and hydraulic properties of weak rockfill during placement and compaction in three dam projects in China. These properties were obtained from laboratory and field tests. Important considerations, such as the control of crushing and crusting and the increase of the permeability of weak rocks, are discussed. Numerical studies on the settlements and slope stability of the dams were conducted and their results were compared with the field measurements. This study provides the opportunities for further understanding the behaviors of CFRDs with weak rocks. [ABSTRACT FROM AUTHOR]

The potential effects of soil liquefaction at level ground sites should be evaluated through examining soil element responses of the individual soil layers and system responses of the soil deposits they form. The cyclic responses and postliquefaction volumetric strain of uniform clean sand, sandy gravel, nonplastic silty sand, and nonplastic silt at the element level can be captured in a unified manner using relative density or the state parameter. The depositional environment should be characterized because geologic details, such as soil fabric, which can be discerned through detailed logging of high-quality continuous sampling, are important in evaluating liquefaction effects. Effective stress analysis enables soil system responses that govern the effects of liquefaction, including the formation of ejecta, to be investigated. A calibrated cone penetration test (CPT) procedure employing the liquefaction ejecta demand parameter captures key aspects of system response and provides an estimate of ejecta-induced building settlement. A probabilistic CPT-based procedure for estimating postliquefaction ground settlement is developed using laboratory and field case history databases. Correlations are developed to estimate Dr or ψo to enable use of the laboratory-based volumetric strain models. Adjustment factors enable the procedure to capture field observations of postliquefaction ground settlement. The proposed ground settlement procedure is combined with shear and ejecta-induced settlement procedures to estimate liquefaction-induced building settlement. [ABSTRACT FROM AUTHOR]

Ground movements caused by deep excavations may potentially lead to building damages in urban cities where the majority of buildings are frame structures. A new damage chart, with two key parameters of the differential settlement and frame dimensions, has been proposed. The chart has been validated against published data, and field measurements have been obtained during the construction of mass rapid transit (North East Line) in Singapore. The proposed chart can be used as an alternative or a supplement to other similar charts. Although the measurement of the frame dimensions is straight forward, the accuracy of the chart highly depends on the predicted building settlement, which still remains a challenge. [ABSTRACT FROM AUTHOR]

A method is presented for estimating the maximum bending moment for continuous (or rigidly jointed) pipelines affected by tunnel-induced ground movement. The estimation can be made based on the knowledge of tunnel and pipeline geometries, the stiffness of soil and pipeline, and tunnel-induced ground deformation at the pipeline level. The method takes account of soil nonlinearity by an equivalent linear approach, in which the stiffness of the soil is evaluated based on an average deviatoric strain developed along the pipeline. The approach is conservative and promises that the bending moment is not underestimated. The validity of the method as an upper bound approximation is evaluated against centrifuge test results. [ABSTRACT FROM AUTHOR]

The exact analytical solutions for the one-dimensional transient consolidation settlement of clay under triangular loadings of pore-water pressure are presented. Using these solutions, two new methods, a “diagnostic curve” method and a “peak derivative” method are developed for a simultaneous estimation of the coefficient of consolidation and final consolidation settlement. The diagnostic curve method uses a master diagnostic curve for matching and the peak derivative method requires locating the peak of a unimodal curve. The proposed methods require only a few but adequate observations of settlements. The peak derivative method has a high diagnostic property for identifying a nonideal condition. [ABSTRACT FROM AUTHOR]

In this research, a numerical investigation was conducted to study the effects of backfill constitutive behavior on the vertical and horizontal deformations of geosynthetic-reinforced soil (GRS) piers under static axial loads. A finite-difference program was used to model full-scale GRS piers. The backfill soil was simulated using three constitutive models: the elastic-perfectly-plastic Mohr-Coulomb model, the plastic-hardening model, and the plastic-hardening model combined with strain-softening behavior. The results showed that the deformation response of GRS piers under service loads is satisfactorily predicted by the plastic-hardening model. At ultimate failure loads, however, only the model accounting for the plastic-hardening and the strain-softening behaviors was judged to reasonably capture the behavior of GRS piers. The relative displacement of soil and geotextile at the soil–geotextile interface was also investigated. The results showed that under working conditions with small applied load, there is no sliding between the soil and geotextile; however, as the load increases, sliding is first initiated at the corners of the pier and progressively mobilized toward the center of the pier. A parametric study on the effects of soil–geotextile interface properties on the deformation behavior of GRS piers under axial loading was also conducted using the validated plastic-hardening model combined with strain-softening behavior. It was found that increasing the interface friction angle decreases the settlement of GRS piers when the axial strain is greater than 2% for piers with a concrete masonry unit (CMU) facing and 4% for piers without CMU facing. The results suggest that when calibrating the interface friction angle (or cohesion), the postyielding response of GRS pier should be used. [ABSTRACT FROM AUTHOR]

A substantial body of laboratory and field observations on compression and consolidation of soft clay and silt deposits as well as organic soils, suggest a soil behavior according to Hypothesis A and the Cα=Cc law of compressibility. Yet the isotaches compression concept and isotaches consolidation models have been used to predict and promote Hypothesis B and also create confusion regarding the Cα=Cc law of compressibility. There is a lack of observed evidence supporting Hypothesis B as it was originally defined. The isotaches compression concept consists of expressing secondary compression observed for 20-mm thick laboratory specimens in terms of vertical strain versus effective vertical stress, for a series of vertical strain rates. The isotaches consolidation models, without justification, then either explicitly or implicitly use secondary compression observed for laboratory specimens during primary consolidation of field layers. These Hypothesis B-based settlement analyses are expected to significantly overestimate end-of-primary (EOP) settlement for field construction on soft ground. [ABSTRACT FROM AUTHOR]

The conventional practice of calculating consolidation settlement in one-dimensional conditions involves dividing soft ground into multiple layers to enable an accurate estimation. However, the effect of layering on consolidation settlement has not been clearly verified. The authors propose an analytical solution to the case where the ground is divided infinitely for normally consolidated soils. The effect of error caused by layering in conventional practice is presented as well. Based on the suggested analytical solution, it is found that the conventional settlement calculation method always underestimates consolidation settlement. In addition, a representative depth for the conventional method in which the soft ground is not divided is suggested for calculating the same consolidation settlement as that obtained by the analytical solution. [ABSTRACT FROM AUTHOR]

Compressibility of recycled materials including bottom ash (BA), foundry slag (FSG), foundry sand (FSD), recycled asphalt pavement (RAP), recycled pavement material (RPM), recycled concrete aggregate (RCA), and recycled asphalt shingle (RAS) mixed with glacial outwash sand (GOS) was evaluated using one-dimensional (1D) compression tests. Results showed that except RCA, compressibility of all the compacted recycled materials is higher than that of the compacted GOS. Different compression mechanisms were attributed to each recycled material depending on the type, composition, and morphological characteristics of the particles. Bituminous recycled materials including RAP, RPM, and RAS-GOS mixtures exhibited relatively higher compressibility compared with nonbituminous recycled materials. At a constant vertical effective stress (σʹv), compression of the recycled materials increased over time with strain rates that are higher for bituminous recycled materials compared to nonbituminous recycled materials. The vertical strain rates (έv) of all the recycled materials log-linearly increased with increasing σʹv. The slope of the log έv - log σʹv curves, termed stress coefficient of compression, is independent of the elapsed time after loading. The stress coefficient of compression indicates degree of stress dependency for compression and is different for each recycled material. Secondary compression ratio is a power function of σʹv indicating that an embankment constructed with recycled materials settles at different rates along the embankment height. Temperature rises increased compressibility of the compacted RAP and RAS-GOS mixtures. On the other hand, thermal preloading significantly reduced the compressibility of the compacted RAP and RAS-GOS mixtures. Construction of embankments containing bituminous materials such as RAP, RPM, or RAS is recommended during summer to induce thermal preloading and reduce long-term settlement. Long-term settlements of typical highway embankments constructed with the recycled materials used in this study were below the allowable limit. [ABSTRACT FROM AUTHOR]