@article{vo_jamaleddin_gabr_borden_2024, title={Natural Frequency and Foundation Damping of Colocated and Hybrid Systems Sharing Wind Turbine Monopiles under Operational Conditions}, volume={24}, ISSN={["1943-5622"]}, url={https://doi.org/10.1061/IJGNAI.GMENG-8469}, DOI={10.1061/IJGNAI.GMENG-8469}, number={1}, journal={INTERNATIONAL JOURNAL OF GEOMECHANICS}, author={Vo, Long and Jamaleddin, Neda and Gabr, Mohammed and Borden, Roy}, year={2024}, month={Jan} } @article{jamaleddin_gabr_borden_argall_lasser_2024, title={Numerical study on micropile group behavior supporting fixed bottom marine hydrokinetic devices in sandy seabed}, volume={293}, ISSN={["1873-5258"]}, url={https://doi.org/10.1016/j.oceaneng.2023.116614}, DOI={10.1016/j.oceaneng.2023.116614}, abstractNote={This study aimed to investigate the behavior of micropile groups supporting fixed bottom marine hydrokinetic (MHK) devices in sandy seabed. A parametric study using PLAXIS 3D was conducted to examine the influence of key design parameters on the lateral load and moment capacity of the micropile group. The parameters considered were micropile diameter, spacing, micropile cap size, number of micropiles, micropile-soil interface properties, and sand packing state. Using the parametric study results, fitting regression techniques were employed to derive equations for predicting the MR (moment resistance in the absence of lateral load) and HR (Lateral resistance in the absence of moment loading), while meeting ultimate limit state (ULS). The equations were formulated based on soil relative density (DR), micropile group polar moment of inertia (J), and an interface reduction factor (Rint). A linear failure envelope is proposed in the Moment-Horizontal (M-H) load space by connecting MR and HR. The proposed framework was then applied to assess the load utilization ratio for various configurations, focusing on a load example of anchoring a 1 MW marine tidal turbine. The results of the study provide insights into the behavior and design of micropile groups supporting fixed bottom MHK devices in sandy seabed.}, journal={OCEAN ENGINEERING}, author={Jamaleddin, Neda and Gabr, Mohammed and Borden, Roy and Argall, Richard and Lasser, Donald}, year={2024}, month={Feb} } @article{tang_borden_gabr_2019, title={Model applicability for prediction of residual soil apparent cohesion}, volume={19}, ISSN={2214-3912}, url={http://dx.doi.org/10.1016/j.trgeo.2019.01.003}, DOI={10.1016/j.trgeo.2019.01.003}, abstractNote={The focus of this paper is on the measurement and prediction of unsaturated shear strength of residual soil as a function of matric suction by utilizing basic soil properties. A total of 19 unsaturated triaxial tests were performed on four groups of undisturbed residual soil specimens with different classifications and compositions. Six compacted specimens were tested and showed lower strength values than those of undisturbed specimens. The cohesion intercept due to matric suction was used to represent the strength contribution of the matric suction, thus accounting for the effect of confining pressure and effective cohesion. The feasibility of three existing models in predicting the apparent cohesion is investigated through comparing computed results to measured data from this paper and literature. A proposed regression equation, developed based on four data sets from the current research and six from the literature, shows an improved ability to predict measured apparent cohesion utilizing basic soil properties. The data set developed herein represent a significant addition to the literature on the unsaturated strength properties of natural residual soil, as sampled from the field.}, journal={Transportation Geotechnics}, publisher={Elsevier BV}, author={Tang, Chien-Ting and Borden, Roy H. and Gabr, Mohammed A.}, year={2019}, month={Jun}, pages={44–53} } @inproceedings{ahsanuzzaman_gabr_borden_2018, title={Effect of seawater on the mechanical properties of cement grout used for formation of micropiles in marine applications}, DOI={10.1061/9780784481592.039}, abstractNote={The deployment of ocean-based renewable energy generation devices, including those utilizing wind, waves, and tidal and ocean currents, requires the installation of cost-effective anchoring foundations. Micropiles provide a viable option for cost-effective subsea anchoring foundations. However, due to the lack of an acceptable approach for the subsea formation of micropiles in sandy soils, no cases that we are aware of have been presented in the literature. The research work reported in this article seeks to investigate the effect of seawater during mixing and curing on compressive strength (fc′) of cement grout for marine micropile anchor systems. Grout mixes are tested at three water-cement ratios (w/c) and in two different curing liquids. Specimens mixed with and cured in fresh water are designated by (ff), those mixed with and cured in seawater as (ss) and those mixed with fresh water and cured in seawater as (fs). A total of 162 cubes and 162 cylinders were cast and exposed to curing liquids for 7, 14, 28, and 90 days. The results showed an appreciable high and early fc′ gain of ss specimens compared to the baseline ff specimens. The rate of fc′ gain of ss specimens reduced slightly at low w/c ratio, but increased at higher w/c ratios (0.5 and 0.6). The reasons for such behavior are related to the accelerated rate of hydration of alite and belite due to the presence of chloride ions (Cl−) in seawater, and the transformation of ettringite (AFt) to monosulfate (AFm) or monochloroaluminate. Scanning electron microscopy (SEM) showed the formation of those crystals at discrete Cl− locations. The ff and fs specimens showed similar rate of fc′ gain (that was not affected by curing in seawater) due to the formation of impermeable layers of brucite [Mg (OH)2] and aragonite (CaCO3) beneath the surface of the fs specimens.}, number={296}, booktitle={Ifcee 2018: innovations in ground improvement for soils, pavements, and subgrades}, author={Ahsanuzzaman, M. and Gabr, Mohammed and Borden, R. H.}, year={2018}, pages={394–403} } @article{hamed mousavi_gabr_borden_2018, title={Resilient modulus prediction of soft low-plasticity Piedmont residual soil using dynamic cone penetrometer}, volume={10}, ISSN={1674-7755}, url={http://dx.doi.org/10.1016/j.jrmge.2017.10.007}, DOI={10.1016/j.jrmge.2017.10.007}, abstractNote={Dynamic cone penetrometer (DCP) has been used for decades to estimate the shear strength and stiffness properties of the subgrade soils. There are several empirical correlations in the literature to predict the resilient modulus values at only a specific stress state from DCP data, corresponding to the predefined thicknesses of pavement layers (a 50 mm asphalt wearing course, a 100 mm asphalt binder course and a 200 mm aggregate base course). In this study, field-measured DCP data were utilized to estimate the resilient modulus of low-plasticity subgrade Piedmont residual soil. Piedmont residual soils are in-place weathered soils from igneous and metamorphic rocks, as opposed to transported or compacted soils. Hence the existing empirical correlations might not be applicable for these soils. An experimental program was conducted incorporating field DCP and laboratory resilient modulus tests on "undisturbed" soil specimens. The DCP tests were carried out at various locations in four test sections to evaluate subgrade stiffness variation laterally and with depth. Laboratory resilient modulus test results were analyzed in the context of the mechanistic-empirical pavement design guide (MEPDG) recommended universal constitutive model. A new approach for predicting the resilient modulus from DCP by estimating MEPDG constitutive model coefficients (k1, k2 and k3) was developed through statistical analyses. The new model is capable of not only taking into account the in situ soil condition on the basis of field measurements, but also representing the resilient modulus at any stress state which addresses a limitation with existing empirical DCP models and its applicability for a specific case. Validation of the model is demonstrated by using data that were not used for model development, as well as data reported in the literature.}, number={2}, journal={Journal of Rock Mechanics and Geotechnical Engineering}, publisher={Elsevier BV}, author={Hamed Mousavi, S. and Gabr, Mohammed A. and Borden, Roy H.}, year={2018}, month={Apr}, pages={323–332} } @article{mousavi_gabr_borden_2017, title={Optimum location of geogrid reinforcement in unpaved road}, volume={54}, ISSN={0008-3674 1208-6010}, url={http://dx.doi.org/10.1139/cgj-2016-0562}, DOI={10.1139/cgj-2016-0562}, abstractNote={This study evaluated the optimum location of a reinforcement layer to maximize the efficiency of the reinforcement inclusion in an unpaved road section. The analyses are used to investigate the optimum location of the reinforcement layer within the aggregate base course (ABC) layer, and provide a possible reason for the improvement in performance. A series of three-dimensional finite element method analyses was performed, and the strain and stress response of a reinforced unpaved road section with two different ABC thicknesses was evaluated. The analyses were conducted under cyclic loading with three different radii of the circular loaded area. The embedded depth of reinforcement was varied within the ABC layer. Results indicate that regardless of ABC layer thickness, the surface deformation is minimized when the reinforcement is embedded at a depth equal to half of the radius of the loaded area (D = 0.5r). A higher tension force is mobilized in the reinforcement element when it is placed at D = 0.5r. It is also shown that the required thickness of ABC is reduced when the reinforcement layer is implemented at the depth at which the maximum vertical strain occurs. Depending on the thickness of the ABC layer, the finite element analysis results indicate that the reinforcement layer could be ineffectual if it is placed at the interface between the ABC and the subgrade layer as is traditionally the case.}, number={7}, journal={Canadian Geotechnical Journal}, publisher={Canadian Science Publishing}, author={Mousavi, S. Hamed and Gabr, Mohammed A. and Borden, Roy H.}, year={2017}, month={Jul}, pages={1047–1054} } @article{mousavi_gabr_borden_2016, title={Correlation of dynamic cone penetrometer index to proof roller test to assess subgrade soils stabilization criterion}, volume={12}, ISSN={1938-6362 1939-7879}, url={http://dx.doi.org/10.1080/19386362.2016.1272751}, DOI={10.1080/19386362.2016.1272751}, abstractNote={The proof roller test has been traditionally carried out as a technique for subgrade quality assessment in road construction and the induced pumping and permanent deformation are used as the basis for subgrade’s pass/fail criteria. The objective of the study presented herein is to assess the feasibility of using the dynamic cone penetrometer index, DCPI, to discern the need for undercut and the quality of subgrade. A series of 3D FEM analysis was performed to develop a subgrade stabilization recommendation chart, based on the predicted properties from DCPI and deformation response under cyclic proof roll loading. The ‘not passing’ criterion (will be referred to herein as ‘failure’ criterion) was determined as a 25 mm permanent deformation under proof roll test. It was determined that the failure deformation occurs at DCPI value of 38 mm/blow for single layer subgrade soil with the Mr/E50 of 6, ratio of resilient modulus to the secant modulus at 50% shear failure. These results are consistent with NCDOT 38 mm/blow undercut criteria. The numerical results indicated that the subgrade with 300 mm stiff layer (DCPI < 20 mm/blow) on top does not require any subgrade soil stabilization given the assumed properties of the underlying layers. On the other hand, the results indicated that subgrade stabilization is required where top 300 mm of the subgrade is a very soft soil layer (DCPI > 60 mm/blow), unless the sublayers underneath are composed of stiff soil (DCPI < 20 mm/blow).}, number={3}, journal={International Journal of Geotechnical Engineering}, publisher={Informa UK Limited}, author={Mousavi, S. Hamed and Gabr, Mohammed A. and Borden, Roy H.}, year={2016}, month={Dec}, pages={284–292} } @article{mousavi_gabr_borden_2017, title={Subgrade resilient modulus prediction using light-weight deflectometer data}, volume={54}, ISSN={0008-3674 1208-6010}, url={http://dx.doi.org/10.1139/cgj-2016-0062}, DOI={10.1139/cgj-2016-0062}, abstractNote={ Resilient modulus has been used for decades as an important parameter in pavement structure design. Resilient modulus, like other elasticity moduli, increases with increasing confining stress and decreases with increasing deviatoric stress. Several constitutive models have been proposed in the literature to calculate resilient modulus as a function of stress state. The most recent model, recommended by the Mechanistic–empirical pavement design guide (MEPDG) and used in this paper, calculates resilient modulus as a function of bulk stress, octahedral shear stress, and three fitting coefficients: k1, k2, and k3. Work in this paper presents a novel approach for predicting resilient modulus of subgrade soils at various stress levels based on light-weight deflectometer (LWD) data. The proposed model predicts the MEPDG resilient modulus model coefficients (k1, k2, and k3) directly from the ratio of applied stress to surface deflection measured during LWD testing. The proposed model eliminates uncertainties associated with needed input parameters for surface modulus (ELWD) calculation, such as the selection of an appropriate value of Poisson’s ratio for the soil layer and shape factor. The proposed model was validated with independent data from other studies reported in the literature. }, number={3}, journal={Canadian Geotechnical Journal}, publisher={Canadian Science Publishing}, author={Mousavi, S. Hamed and Gabr, Mohammed A. and Borden, Roy H.}, year={2017}, month={Mar}, pages={304–312} } @article{cowell_pyo_gabr_borden_kim_2014, title={Performance Assessment of Geosynthetics and Cement as Subgrade Stabilization Measures}, volume={37}, ISSN={0149-6115}, url={http://dx.doi.org/10.1520/GTJ20120206}, DOI={10.1520/gtj20120206}, abstractNote={Work in this paper presents the results of field testing on four instrumented roadway sections constructed on poor subgrade soils and stabilized with select fill, geosynthetics, or cement. Loading was applied using 1000 consecutive truck passes and profile surveying was performed to provide permanent deformation (rutting) data. Peak vertical stresses at the subgrade as well as moisture conditions were also monitored during testing. Results indicated that the deep undercut (31 in./790 mm) with select material backfill section produced the largest cumulative rut depths due to shallow incremental plastic strains induced during each axle pass. The use of a thin Aggregate Base Course (ABC) surface layer (3 in./75 mm) over the select material reduced the rate of rutting. The biaxial geogrid and the high strength geotextile showed a relatively equal performance in all aspects of the study. The cement stabilized section produced a slightly larger average rut depth than the geosynthetically-reinforced sections due to localized areas of pronounced cumulative rutting. However, there were several areas of the soil-cement test section that performed as well as the geosynthetically-reinforced sections.}, number={3}, journal={Geotechnical Testing Journal}, publisher={ASTM International}, author={Cowell, Tim and Pyo, Sangchul and Gabr, Mohammed A. and Borden, Roy H. and Kim, K. J.}, year={2014}, month={Mar}, pages={20120206} } @article{kim_borden_2014, title={Volume-Change Behavior of a Compacted Low-Plasticity Clay From Double-Odometer Tests}, volume={37}, ISSN={["1945-7545"]}, DOI={10.1520/gtj20120047}, abstractNote={Abstract The compressibility of compacted soils is not only a function of soil type and density but also stress state, which is influenced by the existing matric suction and can be described using the fundamentals of unsaturated soil mechanics. This paper presents data from double-odometer tests on low-plasticity clay that demonstrates the effects of dry density and water content on volume-change behavior. Using the data set developed, the drained constrained modulus is determined using the stress–strain relations obtained from conventional odometer tests on soaked specimens, as well as specimens at their molding moisture content. The change of modulus with respect to degree of saturation is discussed and placed in context with the model used in the Guide for Mechanistic-Empirical Design of New and Rehabilitated Pavement Structures [ARA, ERES Consultants Division, 2004, “Guide for Mechanistic-Empirical Design of New and Rehabilitated Pavement Structures,” Final Report NCHRP Project 1-37A, Transportation Research Board of the National Academies, Washington, D.C.]. A procedure for predicting the undrained modulus from the constitutive relation for drained loading and the predicted excess pore pressure caused by loading based on a modification of Hilf’s equation [Hilf, J. W., 1948, “Estimating Construction Pore Pressures in Rolled Earth Dams,” Proceedings of the 2nd International Conference on Soil Mechanics and Foundation Engineering, Vol. 3, International Society for Soil Mechanics and Foundation Engineering (ISSMGE), London, pp. 234–240] is also presented and discussed.}, number={3}, journal={GEOTECHNICAL TESTING JOURNAL}, author={Kim, Wan Soo and Borden, Roy H.}, year={2014}, month={May} } @article{gabr_borden_denton_smith_2013, title={An Insertion Rate Model for Pile Installation in Sand by Jetting}, volume={37}, ISSN={0149-6115}, url={http://dx.doi.org/10.1520/GTJ20120191}, DOI={10.1520/gtj20120191}, abstractNote={The use of jetting is an approach to aid the installation of piles, especially in areas that have hard but relatively shallow subsurface soil layers. Jetting piles for a portion of their installation depth minimize their exposure to excessive driving stress and provide energy savings and noise reduction. However, the literature offers little information regarding the appropriate selection of jetting parameters, such as flow rate and jet velocity, which are needed to produce the desired installation times as a function of soil strength. This paper presents a model for estimating pile jetting parameters based on the results from laboratory and field testing. The model is based on an idealization of the applied shear stress that is produced by the jet as well as the soil resistance to pile insertion. The model is applied to 19 field installations where the jetted depths of the piles range from 10–34 ft. The field data yield ratios of 6–20 for the jet flow rate (Qw) to the rate of the pile volume insertion in terms of time (Qp), with the lower ratios associated with higher jet velocities. The proposed model yields an estimated Qw/Qp that is within +/− 20 % of the measured values.}, number={1}, journal={Geotechnical Testing Journal}, publisher={ASTM International}, author={Gabr, M. A. and Borden, Roy H. and Denton, R. L. and Smith, Alex W.}, year={2013}, month={Oct}, pages={20120191} } @article{kim_borden_2013, title={Numerical Simulation of MSE Wall Behavior Induced by Surface-Water Infiltration}, volume={139}, ISSN={["1943-5606"]}, DOI={10.1061/(asce)gt.1943-5606.0000927}, abstractNote={AbstractA series of numerical simulations, including transient seepage analyses and stress deformation analyses, was performed to predict the behavior of a mechanically stabilized earth (MSE) wall subjected to surface-water infiltration. In this research, two mechanisms to cause the deformation because of wetting were considered: (1) the deformation induced by shear strength decreases and (2) the volumetric deformation (swell or collapse) because of wetting. The effects of low as-compacted water content and a low-quality compaction zone behind the wall face on the wall behavior were investigated. As result of the simulations, the wall deformations (face deflections and reinforced-soil settlements) and reinforcement tensions (maximum tensions) are presented at the end of construction and after periods of surface-water infiltration.}, number={12}, journal={JOURNAL OF GEOTECHNICAL AND GEOENVIRONMENTAL ENGINEERING}, author={Kim, Wan Soo and Borden, Roy H.}, year={2013}, month={Dec}, pages={2110–2124} } @article{cote_robinson_gabr_borden_2013, title={Performance-Cost Analysis of Stabilized Undercut Subgrades}, volume={139}, ISSN={["0733-9364"]}, DOI={10.1061/(asce)co.1943-7862.0000572}, abstractNote={AbstractAn approach for comparatively evaluating the performance cost of undercut subgrade stabilization measures is presented. The performance-cost analysis coupled results from laboratory cyclic load testing with material prices and estimated cost factors for stabilization alternatives. The study utilized data from 22 simulated undercut sections with different stabilization configurations over a soft subgrade with a California bearing ratio of approximately 2.0%. The computed cost factors are normalized with respect to the rut-depth magnitude and subgrade strength. Sections with lime-stabilized subgrade were the most economical with respect to initial and postrut repair cycles. Unreinforced aggregate based course (ABC) sections between 356 and 508 mm (14 and 20 in.) in thickness were economical during initial cycles. Sections with geosynthetic reinforcement showed that once enough rut depth is induced to mobilize the strength of the reinforcement, economical performance was comparable with other stabili...}, number={2}, journal={JOURNAL OF CONSTRUCTION ENGINEERING AND MANAGEMENT-ASCE}, publisher={American Society of Civil Engineers (ASCE)}, author={Cote, Benjamin and Robinson, Brent and Gabr, M. A. and Borden, Roy H.}, year={2013}, month={Feb}, pages={121–127} } @article{park_gabr_robinson_borden_2012, title={Subgrade Undercut Criteria Based on Modeling of Rutting and Pumping Response}, volume={138}, ISSN={1090-0241 1943-5606}, url={http://dx.doi.org/10.1061/(ASCE)GT.1943-5606.0000695}, DOI={10.1061/(asce)gt.1943-5606.0000695}, abstractNote={AbstractThe stability of subgrade soils is a major concern during roadway construction with inappropriately soft layers often undercut and replaced by competent or stabilized materials. Systematic undercut criteria are established using numerical modeling with varying the strength and stiffness parameters of the subgrade and representing the mechanistic behavior as an elastic-perfectly plastic medium. Two modes of domain configurations were considered: the plane strain and axisymmetric conditions. The plane strain mode is assumed to simulate proof roller loading with four parallel tires and mainly provides information about excessive pumping response as materials at deeper layers are affected. The axisymmetric mode provides information related to excessive rutting and is used to simulate the effect of single or dual tires representing construction traffic, rather than a series of closely spaced axle loads. Undercut criteria are proposed for meeting a deformation limit state of 25 mm for both pumping and r...}, number={10}, journal={Journal of Geotechnical and Geoenvironmental Engineering}, publisher={American Society of Civil Engineers (ASCE)}, author={Park, Young Jin and Gabr, Mohammed A. and Robinson, Brent R. and Borden, Roy H.}, year={2012}, month={Oct}, pages={1175–1184} } @article{kim_borden_2011, title={Influence of soil type and stress state on predicting shear strength of unsaturated soils using the soil-water characteristic curve}, volume={48}, ISSN={["1208-6010"]}, DOI={10.1139/t11-082}, abstractNote={ Comprehensive studies on the prediction of unsaturated shear strength were performed using three commonly used empirical procedures: Fredlund et al. approach (published in 1996), Vanapalli et al. approach (published in 1996), and Khalili and Khabbaz method (published in 1998). Shear strength data published in the literature for 15 soils were examined using these procedures. Comparisons between measured and predicted values of unsaturated shear strength are presented for different soil types. The effect of stress state on the prediction of shear strength is also discussed. }, number={12}, journal={CANADIAN GEOTECHNICAL JOURNAL}, author={Kim, Wan Soo and Borden, Roy H.}, year={2011}, month={Dec}, pages={1886–1900} } @article{suits_sheahan_cote_robinson_pyo_park_gabr_borden_2010, title={Laboratory Performance Comparison of Stabilized Undercut Subgrade Under Cyclic Loading}, volume={33}, DOI={10.1520/gtj102935}, abstractNote={Abstract This study evaluated the performance of undercut subgrade stabilization measures during construction traffic loading prior to final paving. Twenty-two simulated undercut sections with different stabilization configurations over a typically undercut Coastal Plain clay subgrade were built in a large-scale test pit. The subgrade was placed at a California Bearing Ratio of ∼2–3 % and stabilized with granular layers, granular layers reinforced with geosynthetics, and lime. Granular layers consisted of either aggregate base course (ABC), sandy select fill, or a multi-layer system with both soil types. The four geosynthetics tested were a woven reinforcement geotextile, a woven separation geotextile, and two biaxial polypropylene geogrids. The soft nature of the subgrade and its consequences on the ability to compact the ABC layer show the importance of carefully analyzing the results when viewed on a comparative basis. Cyclic plate loading simulating construction traffic showed that thicker granular layers produced less surface displacement, barring subgrade strength differences from remolding effects. Tests with lime stabilized subgrade showed the least magnitude of deformation over initial and post-rut repair cycles. ABC tests with geotextile showed improvement over unreinforced sections but only when placed at depths approximately equal to the loading plate diameter and after initial displacements mobilized the geosynthetic strength.}, number={6}, journal={Geotechnical Testing Journal}, publisher={ASTM International}, author={Suits, L. D. and Sheahan, T. C. and Cote, Benjamin and Robinson, Brent and Pyo, Sangchul and Park, Young Jin and Gabr, Mohammed and Borden, Roy}, year={2010}, pages={102935} } @article{park_gabr_borden_2010, title={Discussion of "p-y Criterion for Rock Mass" by Robert Liang, Ke Yang, and Jamal Nusairat}, volume={136}, ISSN={["1943-5606"]}, DOI={10.1061/(asce)gt.1943-5606.0000171}, number={1}, journal={JOURNAL OF GEOTECHNICAL AND GEOENVIRONMENTAL ENGINEERING}, publisher={American Society of Civil Engineers (ASCE)}, author={Park, Y. J. and Gabr, M. A. and Borden, R. H.}, year={2010}, month={Jan}, pages={272–274} } @article{ahn_cote_robinson_gabr_borden_2009, title={Inverse Analysis of Plate Load Tests to Assess Subgrade Resilient Modulus}, volume={2101}, ISSN={["2169-4052"]}, DOI={10.3141/2101-13}, abstractNote={ Cyclic plate load testing is commonly used to investigate subgrade response under repetitive loads. Two frameworks for performing inverse analysis are described for backcalculating resilient moduli on the basis of measured key outputs. In the first approach, an elastic modulus is back-calculated in each selected domain; in the second, selected parameters in the resilient modulus model are estimated. The axisymmetric finite element model analysis results suggest that the second approach is more robust because it allows the modulus to be distributed in the selected domain. A series of sensitivity analyses was conducted with the second approach to illustrate how the assumed properties or model geometry affects the backcalculated parameters. Discrepancies between the back-calculated parameters and their known values were observed when the distance to the boundary–-that is, the radial distance from centerline to sidewall–-was not properly assigned. When backcalculating only selected parameters in the resilient modulus equation, it is necessary to assign the other parameters carefully (i.e., from laboratory tests or references). An example analysis shows the application of the proposed approach to an actual plate load test. }, number={2101}, journal={TRANSPORTATION RESEARCH RECORD}, publisher={Transportation Research Board}, author={Ahn, Jaehun and Cote, Benjamin M. and Robinson, Brent and Gabr, Mohammed A. and Borden, Roy H.}, year={2009}, pages={110–117} } @inproceedings{gabr_borden_smith_denton_eggleston_broome_2008, title={Sustainability In coastal construction: Characterization and ecological impact of jetting-induced disturbance zones}, booktitle={New Horizons in Geotechnical and Geoenvironmental Engineering, Tanta University, Egypt, September 2008}, author={Gabr, M. A. and Borden, R. H. and Smith, A. W. and Denton, R. L. and Eggleston, D. B. and Broome, S. W.}, year={2008} } @article{cho_gabr_clark_borden_2007, title={Field P-y curves in weathered rock}, volume={44}, ISSN={["0008-3674"]}, DOI={10.1139/t07-026}, abstractNote={In weathered and decomposed rock profiles, the lack of an acceptable analysis procedure for estimating lateral load–displacement response of drilled shafts is compounded by the unavailability of weathered material properties, including the material's lateral subgrade reaction modulus. Such deficiency often leads to the overdesign of the drilled shaft foundation. Six field tests were conducted on drilled shafts to investigate the shape and magnitude of P–y curves in weathered rock material at three locations in North Carolina. The tested shafts were instrumented using dial gages, strain gages, and continuous vertical inclinometers. The measured load versus deflection data are used to study the stiffness response of weathered rock. Measured lateral responses are compared with the results estimated based on a "weak rock" model and a stiff clay model. The comparison shows that Reese's weak rock model overestimated the resistances of the tested shafts while the stiff clay model consistently underestimated the measured shaft resistances. The measured and computed results are analyzed and discussed.Key words: drilled shaft, weathered rock P–y curve, subgrade modulus, ultimate resistances in weathered rock, verification tests.}, number={7}, journal={CANADIAN GEOTECHNICAL JOURNAL}, publisher={Canadian Science Publishing}, author={Cho, Kook Hwan and Gabr, Mohammed A. and Clark, Shane and Borden, Roy H.}, year={2007}, month={Jul}, pages={753–764} } @inproceedings{gabr_borden_smith_denton_eggleston_broome_2006, title={Characterization of jetting-induced disturbance zones}, booktitle={3rd Annual GEO3 T2 conference & expo 2006, Charlotte, April, 2006}, publisher={Raleigh, NC: NC Department of Transportation}, author={Gabr, M. A. and Borden, R. H. and Smith, A. W. and Denton, R. L. and Eggleston, D. B. and Broome, S. W.}, year={2006} } @article{lee_rust_hamouda_kim_borden_2005, title={Fatigue cracking resistance of fiber-reinforced asphalt concrete}, volume={75}, ISSN={["0040-5175"]}, DOI={10.1177/004051750507500206}, abstractNote={ The influence of fibers on the fatigue cracking resistance of asphalt concrete is investigated using fracture energy. Nylon, a popular facing yarn of carpets, is used for the actual recycled carpet fibers in asphalt pavement. The experimental program is designed with two phases: the single fiber pull-out test and the indirect tension strength test. Through pull-out tests of 15-denier single nylon fibers, the critical fiber embedded length is determined to be 9.2 mm. As for indirect tension strength tests, samples of asphalt concrete mixed with nylon fibers of two lengths, 6 and 12 mm, based on results of the pull-out tests (critical embedded length) and three volume fractions, 0.25, 0.5, and 1%, are prepared and tested. Asphalt concrete samples fabricated with fibers of 1% and 12 mm results in 85% higher fracture energy than non-reinforced specimens, showing improved fatigue cracking resistance. Although an optimized asphalt mix design with fibers has not been developed for this study, the increased fracture energy represents a potential for improving asphalt fatigue life, which may be facilitated through the use of recycled carpet fibers. }, number={2}, journal={TEXTILE RESEARCH JOURNAL}, author={Lee, SJ and Rust, JP and Hamouda, H and Kim, YR and Borden, RH}, year={2005}, month={Feb}, pages={123–128} } @article{cho_clark_keaney_gabr_borden_2001, title={Laterally Loaded Drilled Shafts Embedded in Soft Rock}, volume={1772}, ISBN={0309072360}, DOI={10.3141/1772-01}, abstractNote={ The current design criterion for laterally loaded drilled shafts embedded in weathered Piedmont rock profiles requires a challenging effort on the part of the engineer. A substantial cost saving could be realized, while maintaining an acceptable and safe performance, if a rational method were developed for the analysis and design of drilled shafts in such a profile. In a current research project, the primary objective is to develop and validate a procedure for design and analysis of laterally loaded drilled shafts embedded in the Piedmont weathered rock profiles. A major component of this research is a field-testing program. Presented are the results of the first in a series of several lateral load tests performed on two drilled shafts 0.762 m (30 in.) in diameter embedded in Piedmont weathered rock. These shafts were instrumented with inclinometers and strain gauges. Field data obtained from the instrumented shafts were used to develop P-y curves. Field testing also encompassed the use of a borehole dilatometer to establish correlations between the rock strength and deformation parameters and potential P-y curves. A comparison is made between backcalculated P-y curves, P-y curves predicted by using Reese’s method, and P-y curves from the rock dilatometer. Loaddeformation results are presented and discussed for all methods used. }, number={1772}, journal={Transportation Research Record: Journal of the Transportation Research Board}, publisher={Transportation Research Board}, author={Cho, Kook and Clark, Shane and Keaney, Brian and Gabr, Mohammed and Borden, Roy}, year={2001}, month={Jan}, pages={3–11} } @article{wang_borden_1998, title={Deformation characteristics of Piedmont residual soils - Closure}, volume={124}, DOI={10.1061/(ASCE)1090-0241(1998)124:6(556)}, number={6}, journal={Journal of Geotechnical and Geoenvironmental Engineering}, author={Wang, C. C. E. and Borden, R. H.}, year={1998}, pages={556–557} } @article{borden_shao_gupta_1998, title={Dynamic properties of Piedmont residual soil - Closure}, volume={124}, DOI={10.1061/(ASCE)1090-0241(1998)124:6(554)}, number={6}, journal={Journal of Geotechnical and Geoenvironmental Engineering}, author={Borden, R. H. and Shao, L. S. and Gupta, A.}, year={1998}, pages={554–555} } @inproceedings{borden_1997, title={An argument in favor of specifications containing grouted soil strength tests at multiple strain rates}, booktitle={Grouting: Compaction, remediation and testing: Proceedings of sessions sponsored by the Grouting Committee of the Geo-Institute of the American Society of Civil Engineers in conjuction with the Geo-Logan '97 Conference, Logan, Utah, July 16-18, 1997 (Geotechnical special publication; no. 66)}, publisher={New York: American Society of Civil Engineers}, author={Borden, R. H.}, year={1997}, pages={173–187} } @inproceedings{borden_1997, title={Compaction grouting}, booktitle={Ground improvement, ground reinforcement, ground treatment: Developments 1987-1997; Proceedings of sessions sponsored by the Committee on Soil Improvement and Geosynthetics of the Geo-Institute of the American Society of Civil Engineers in conjunction with Geo-Logan '97, Logan, Utah, July 17-19, 1997}, publisher={New York: American Society of Civil Engineers}, author={Borden, R. H.}, year={1997}, pages={34–45} } @inproceedings{borden_ivanetich_1997, title={Influence of fines content on the behavior of compaction grout}, booktitle={Grouting: Compaction, remediation and testing: Proceedings of sessions sponsored by the Grouting Committee of the Geo-Institute of the American Society of Civil Engineers in conjuction with the Geo-Logan '97 Conference, Logan, Utah, July 16-18, 1997 (Geotechnical special publication; no. 66)}, publisher={New York: American Society of Civil Engineers}, author={Borden, R. H. and Ivanetich, K. B.}, year={1997}, pages={62–75} } @article{malone_stjohn_barlaz_borden_1997, title={Potential toxicity and aerobic biodegradability of sodium silicate chemical grout leachate}, volume={16}, ISSN={["1552-8618"]}, DOI={10.1897/1551-5028(1997)016<0442:PTAABO>2.3.CO;2}, abstractNote={Environmental Toxicology and ChemistryVolume 16, Issue 3 p. 442-446 Environmental Chemistry Potential toxicity and aerobic biodegradability of sodium silicate chemical grout leachate J. Michael Malone, J. Michael Malone Department of Civil Engineering, North Carolina State University, Raleigh, North Carolina 27695–7908, USASearch for more papers by this authorTodd W. St. John, Todd W. St. John Department of Civil Engineering, North Carolina State University, Raleigh, North Carolina 27695–7908, USASearch for more papers by this authorMorton A. Barlaz, Corresponding Author Morton A. Barlaz Department of Civil Engineering, North Carolina State University, Raleigh, North Carolina 27695–7908, USADepartment of Civil Engineering, North Carolina State University, Raleigh, North Carolina 27695–7908, USASearch for more papers by this authorRoy H. Borden, Roy H. Borden Department of Civil Engineering, North Carolina State University, Raleigh, North Carolina 27695–7908, USASearch for more papers by this author J. Michael Malone, J. Michael Malone Department of Civil Engineering, North Carolina State University, Raleigh, North Carolina 27695–7908, USASearch for more papers by this authorTodd W. St. John, Todd W. St. John Department of Civil Engineering, North Carolina State University, Raleigh, North Carolina 27695–7908, USASearch for more papers by this authorMorton A. Barlaz, Corresponding Author Morton A. Barlaz Department of Civil Engineering, North Carolina State University, Raleigh, North Carolina 27695–7908, USADepartment of Civil Engineering, North Carolina State University, Raleigh, North Carolina 27695–7908, USASearch for more papers by this authorRoy H. Borden, Roy H. Borden Department of Civil Engineering, North Carolina State University, Raleigh, North Carolina 27695–7908, USASearch for more papers by this author First published: 26 October 2009 https://doi.org/10.1002/etc.5620160308Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Abstract Large quantities of organic reagents are used in sodium silicate grouts for the stabilization of granular soils prior to construction projects. However, the fate and effects of these reagents in the subsurface are unknown. In this study, leachate from sodium silicate grouted soil specimens was tested for acute toxicity using Daphnia magna and Vibrio fisheri (Microtox®) assays. Additionally, a soil biometer test was used to measure the aerobic biodegradability of the grout leachate. Median lethal concentrations (LC50s) ranged from 1,220 to 3,260 mg/L as total organic carbon (TOC) for the D. magna test and from 4,500 to 22,180 mg/L as TOC for the Microtox test. More than 80% of the organics contained in the grout leachate were biologically converted to carbon dioxide in less than 30 d. The grout was found to be far less toxic than other common organic chemicals such as phenol. Volume16, Issue3March 1997Pages 442-446 RelatedInformation}, number={3}, journal={ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY}, author={Malone, JM and StJohn, TW and Barlaz, MA and Borden, RH}, year={1997}, month={Mar}, pages={442–446} } @book{borden_geng_1997, title={Three dimensional slope stability analysis and support strategies for conical excavations: Final report to Carolina Power and Light}, publisher={Carolina Power and Light}, author={Borden, R. H. and Geng, C.}, year={1997} } @inproceedings{gabr_borden_1989, title={Influence of sloping surface on lateral load-deflection response of rigid piers}, ISBN={9789061918905}, booktitle={Proceedings of the twelfth international conference on soil mechanics and foundation engineering, Rio de Janeiro/13-18 August 1989}, publisher={Brookfield, VT: A.A. Balkema}, author={Gabr, M. A. and Borden, R. H.}, year={1989} } @inproceedings{gabr_borden_1988, title={Analysis of load deflection response of laterally loaded piers using DMT}, ISBN={9789061918011}, booktitle={Penetration testing, 1988 :proceedings of the First International Symposium on Penetration Testing, ISOPT-1, Orlando, 20-24 March 1988}, publisher={Brookfield, VT: A.A. Balkema}, author={Gabr, M. A. and Borden, R. H.}, year={1988} }