To investigate the development of pore pressures in the air-confined system with a rise of groundwater under a geomembrane, a laboratory test was conducted. Then, a numerical model with the consideration of the water-gas-solid three-phase system was developed based on the hydro-mechanical coupling theory for unsaturated soils. The model was validated by the experimental result and then a numerical

Construction over soft soil is a challenge as the ground can be too soft to work on it. To overcome this, a working platform has to be formed before any soil improvement work can be carried out. One of such methods was proposed by Broms (1987) which uses geotextile and sand berms. In this paper, a modified Broms' method is proposed to use geotextile tubes to confine the sand berms. A new analytical

Geosynthetic reinforced soil embankment are extensively applied in the construction of high-speed railway and highway in mountainous regions but limited field monitoring is conducted on high and steep cases. Aiming to acquire better understanding, a 33-m-high single-tiered wrapped-facing geogrid reinforced soil embankment with the slope of 1 V:0.5H in China was monitored for 2 years during and after

In view of the deep dewatering of landfill sludge (LS) that had been buried for more than ten years in Shanghai, Fenton's reagent combined with a vacuum preloading method was proposed. First, a vacuum filtration test was carried out to study the optimal amount of Fenton's reagent for LS. Then, four filter membranes with different pore sizes were used for a vacuum preloading model box test to study

In the case of the rockfall hazards, multiple rockfall impacts usually occur. To improve the ductility and the multi-impact resistance ability of the rock-shed, geofoam is proposed to replace part of sand, forming a composite cushion. Two types of geofoam are selected in the paper, namely, expandable polyethylene (EPE) and expanded polystyrene (EPS). A systematic experimental study was conducted to

Construction of mechanically stabilized earth (MSE) walls in multi-tiered configurations is a promising solution for increasing the height of such walls. The good performance of this type of walls after recent major earthquakes was reported in a number of technical studies. In the present study, an experimental approach was adopted to compare the seismic performance of single-tiered and multi-tiered

The deformation performance and settlement failure mechanism of geosynthetics-reinforced soil (GRS) walls are the two key points of engineering design under the differential settlement. This paper presents model tests of deformation performance and failure mechanism of the GRS wall with and without lateral restriction under differential settlement conditions. The observation and measurement results

This paper presented a field study of the reinforced soil wall (RSW) with a geogrid wrap-around facing. In addition to the conventional monitoring content, the strain of the face-wrapping geogrid, which was neglected in most previous studies, was monitored during the construction process. The positional relationship between the maximum vertical earth pressure and horizontally laid geogrid strain was

The current study addresses the cracking and self-healing capacity of Geosynthetic clay liners (GCLs) subjected to drying and wetting in a divalent salt solution. Commercially available GCLs, initially saturated under a load of 3.92 kPa, were stepwise dried for different durations in an oven at 30 °C and rewetted afterwards in deionised water and divalent salt solutions (CaCl2) of different molarities

Turbidity curtains, also called as turbidity barriers and silt curtains, were designed to contain plumes of suspended solids in water bodies. The high concentration of suspended solids in the raw water impacts on the costs of its treatment. Water with higher turbidity requires more coagulants in water treatment and needs a sludge management. In order to reduce turbidity in the water intake, the present

The internal shear strength of a geosynthetic clay liner (GCL) within composite liner systems is crucial for the stability of landfills and should be carefully considered in the design. To explore the shear strength and failure mechanism of the extensively used needle-punched GCL, a series of displacement-controlled direct shear tests with five normal stress levels (250–1000 kPa) and eight displacement

In the recent past, the wraparound geosynthetic reinforcement technique has been recommended for constructing the geosynthetic-reinforced soil foundations. This paper presents the development of an analytical expression for estimating the ultimate bearing capacity of strip footing resting on soil bed reinforced with geosynthetic reinforcement having the wraparound ends. The wraparound ends of the geosynthetic

Experiments were conducted to investigate how specimen preparation (crushing and sieving) affects the swell index (SI) of bentonite-polymer (B–P) composites and the relationship between SI and hydraulic conductivity of B–P GCLs. Seven B–P and one Na–B GCLs were used in this study. Tests were conducted using DI water and synthetic municipal solid waste incineration ash leachates. Specimens were prepared

Whether the so-called double porosity in soils with a loose and natural packing state is a concept with real-world implications is a fundamental yet controversial question in the study of cyclic undrained shear behaviour of fibre-reinforced silty sands. An attempt is made here to clarify the question by means of particle-level modelling combined with 41 undrained cyclic triaxial shear tests. The study

In composite liners made of geomembrane (GMB)-geosynthetics clay liners (GCLs), maintaining bentonite in the GCL in a suitably hydrated state is critical for their performance. Hydration of GCL from subsoil, following industry best practice, is time consuming and conditional on suitable water chemistry in subsoil. In addition, under thermal gradients, dehydration occurs, with moisture migrating downwards

The hydraulic conductivity of geosynthetic clay liners (GCLs) permeated with deionized water (S0) and NH4+ solutions, with concentrations of 100 mg/L (S100) and 1000 mg/L (S1000), was examined under six dry-wet cycles. The internal properties of virgin, desiccated, and healed GCLs were analyzed and quantified using X-ray computed tomography images. The hydraulic conductivity of the GCLs permeated with

The paper demonstrates deterministic and reliability-based assessment of strength limit states (tensile resistance and pullout) and the service limit state for soil failure for mechanically stabilized earth (MSE) walls constructed with polyester (PET) strap reinforcement. The general approach considers the accuracy of the load and resistance models that appear in each limit state equation plus uncertainty

Reinforced subgrade for railways (RSR) is a construction method in which reinforced subgrade is constructed first and a rigid facing wall later to minimize the residual settlement after the service of a roadbed. The RSR was designed and constructed at Osong railway test line in Korea. In this study, load sharing capacities from the reinforced subgrade to the rigid facing wall of it were evaluated through

Dynamic responses of the geosynthetic-encased stone column (GESC) supported embankment under traffic loads have become a hot topic. This study investigates the responses of GESC improved ground under vertical cyclic loading. A series of laboratory tests in a designed model test tank have been carried out with different loading parameters (varied loading amplitudes and frequencies), different column

The mechanical properties of geosynthetic reinforcements are known to be time-, environment- and stress-dependent. Characterization of these reinforcement properties is often assessed under controlled laboratory settings and extrapolated to the design life of geosynthetic-reinforced soil structures. However, despite the wide application of geosynthetic reinforcement in earth retaining structures, there

In this study, the contribution of single and multiple layers of geogrids to bearing capacity and stress behavior was determined by laboratory experiments. The effects of parameters such as the depth of the first geogrid, the vertical spacing between the geogrid layers and the number of geogrid layers on the bearing capacity and settlement behavior of soil and stress distribution on geogrid and pipe

Previous investigators have found increasing rates odf consolidation with increasing degrees of soft clay improvement using PVD only, Vacuum-PVD, Thermo-PVD and Thermo-Vacuum-PVD). This paper utilized scanning electron microscope (SEM) to evaluate and compare the microstructures of the clay specimens obtained from within the smear zone of both undisturbed and reconstituted samples in small consolidometer

The desiccation and subsequent hydraulic conductivity of both a standard (GCL_A) and polymer-enhanced (GCL_B) Na-bentonite GCL hydrated from a well-graded sandy subsoil under 20 kPa, then subjected to a thermal gradient, and finally rehydrated and permeated with distilled water or 0.325 mol/L Na+ synthetic brine are reported. With moderate temperature of 40 °C applied to the top of the liner, GCL_B

Geosynthetic-reinforced structures are required for constructing roads in the presence of trench voids. In this study, we propose a novel method with respect to the geosynthetic-reinforced cohesive subgrade spanning trench or column voids. Using this method, we can estimate the geosynthetics deformation w and strain ε by considering various load patterns, the upper interface friction of geosynthetics

Construction of this 67 m high RSS was completed in December 2006. After seven years in-service, a tension crack was observed at the top of the slope. In March 2015 this RSS structure catastrophically collapsed. This RSS structure collapsed in a compound failure mode; as the failure plane passed beneath, partially behind, and partially through the reinforced soil mass. The failure plane beneath the

Aqueous diffusion of trichloroethylene (TCE) and tetrachloroethylene (PCE) is examined for high density polyethylene (HDPE), linear low density polyethylene (LLDPE), polyurethane/urea, and two polyethylene (PE) geomembranes coextruded with ethylene vinyl alcohol (EVOH). Additionally, the diffusion of benzene, toluene, ethylbenzene, and xylenes through polyurethane/urea geomembrane is examined. Permeation

The self-healing of a GCL with artificial defects (circular holes and rectangular slits, both with and without the carrier geotextile preserved below the holes) upon hydration on a Godfrey silty sand (GSS) subgrade with wfdn = 5, 10 and 16% under 2–100 kPa is examined. Circular holes with the carrier geotextile missing below holes with diameters up to 25.4 mm self-healed on the wfdn = 5% and 10% GSS

Landfills are sequentially filled by solid waste lifts, thus normal stress on the liner interface changes in different shear stages, which may affect selection of interface strength in landfill slope stability analysis. Shear tests were conducted at the liner interfaces of geomembrane/geotextile (GM/GT) and geomembrane/geocomposite/sand (GM/GC/Sand), and the normal stress changed in different shear

The basic pore unit model is extended to predict the strained pore size characteristics of woven slit-film geotextiles subjected to unequal biaxial tensile strains. The strained per cent open area (POA) and analytical pore size are expressed as functions of the weft strain and the warp strain to weft strain ratio. The influence of the biaxial tensile strain on pore size characteristics is evaluated

This study investigates the influence of clogging substances on pore characteristics and permeability of geotextile envelopes that were used for 3, 7 and 15 years in irrigated farmlands in Xinjiang region, which is arid and suffers from the soil salinity problem. Results show that the macropores (above 125 μm) of envelopes are evidently clogged, whereas the smaller pores less than 100 μm are still

Plate loading tests were conducted to investigate the effect of a bottom boundary condition on the pressure-settlement behavior of a footing on sand with a limited thickness involving geosynthetics. Seven boundary materials including geosynthetics were used to create different boundary conditions at the bottom of the sand. Interface direct shear tests were conducted first to determine the interface

The equivalent strength and stiffness of geosynthetic-encased soil are two important parameters for analysis of cellular geosynthetic-reinforced foundations and earth structures. However, limited analytical approaches exist for the estimation of these parameters, and this limitation hinders their applications in geotechnical engineering practice. In this study, an analytical method is proposed for

A modified osmotic suction control technique for monitoring apparent transient weight changes was successfully adapted to the wetting and drying paths of geosynthetic clay liners (GCLs). Reasonable control was possible, enabling suction equilibrium to be achieved without disruption to the test. The results provide unique insight into the time-dependent changes in water retention properties and the

Vertical stiffness and shear strength of ballasts are significantly degraded when contaminated with sands. There is a lack of solutions/studies related to strengthening ballast against sand contamination. Addressing this limitation, a comprehensive laboratory investigation was made on effectiveness of geogrid reinforcement for improvement of mechanical properties of sand-contaminated ballast. To this

Flexible, sand-filled, geotextile bags (geobags) have been used in both India and Bangladesh along the banks of the Brahmaputra for protection against riverbank erosion. Geotextile containers have been researched extensively for their use in coastal structures; however, there is a gap in knowledge of the application of smaller geobags used in riverbank protection structures. In 2018, flume experiments

This study proposes a procedure for predicting the required tensile strength of geosynthetics for three-dimensional (3D) geosynthetic-reinforced soil structures (GRSSs) comprised of cohesive backfills subjected to earthquake loadings. This procedure is undertaken using the kinematic approach of limit analysis together with a pseudo-dynamic approach. The influence of cracks is incorporated into the

This paper proposes a method to predict the lateral earth pressures on nonyielding retaining walls with geofoam inclusions. The previous study of the lateral stress-strain relation of the backfill was extended, and the solution was derived by the iterative method. The proposed solution could be applied without the known value of the compression of the geofoam inclusions. Model tests for nonyielding

This technical paper presents a unique comparison of geomembrane factory and field welded thermal seams for a large off-stream water reservoir project. The results of the comparison show that factory welded seams exhibit higher seam peel and shear strengths at yield, less variability, and more consistency than field welded thermal seams. In particular, the results show that factory seams are about

In this study, an experimental investigation has been conducted on a circular footing model subjected to eccentric load resting on the geonet-reinforced sand. To this end, five series of tests were carried out in order to evaluate the effect of reinforcement dimension and eccentricity on the bearing capacity, settlement, and rotation of the footing. Results show that the bearing capacity ratio (BCR)

This research evaluates the shear strength properties of unreinforced and geogrid-reinforced ladle furnace slag (LFS), electric arc furnace slag (EAFS) and a blend comprising 50% LFS and 50% EAFS (LFS50+EAFS50) using the large direct shear testing apparatus (DST). The large DST results of unreinforced steel slags indicated that LFS had the lowest shear stress ratio at the peak shear strength among

A simplified equation, which allows for the calculation of the tension force using the actual tube height and pumping pressure with the flexibility to use a coefficient of lateral pressure (K), is proposed and validated theoretically by comparing the proposed method with two well-known methods in the literature, and experimentally, by conducting several half cross-section tests. The half cross-section

This paper proposes using geofoam blocks to improve the safety of buried steel pipelines under permanent ground deformation due to strike-slip fault rupture. Since these geofoam blocks are deformable, they can compress during fault rupture and thus reduce the pressure imposed on the pipeline by the surrounding soil. This means that the pipe can sustain a higher level of tectonic deformations. For the

Rail tracks continue to deform due to degradation of ballast under the application of heavy train traffic. The resulting track deformations often lead to drainage impairment as well as loss of resiliency. For track replenishment, deep screening of ballast is usually adopted by Indian Railway (IR) either after 10 years or passage of 500 MGT traffic, whichever is earlier. To study the effectiveness of

This paper presents a study on stochastic evaluation of leakages through holes in wrinkle networks of composite liners. The statistical parameters of wrinkles are used as indexes to describe the spatial distributions of wrinkles in a wrinkle network and the wrinkle density is modeled as a random field in the proposed approach, which allows the construction of a database about how wrinkles may be distributed

This study proposes an analytical method for the calculation of the safety factor against lateral spreading in embankments, both for cases with and without basal reinforcement. Hence, a new limit equilibrium approach is presented based on the lower bound plasticity theorem, which allows the computation of the required distribution of stresses along presumed slip surfaces at the limit state. Comparing

Reliably estimating soil vertical compression under vacuum loading is still challenging for geotechnical engineers. In this paper, the soil vertical compression within the prefabricated vertical drain (PVD)-improved zone under vacuum pressure was investigated based on the theoretical analysis, reported laboratory tests and the case histories. A theoretical equation was developed to evaluate the effect

A scaled plane-strain shaking table test was conducted in this study to investigate the seismic performance of a Geosynthetic Reinforced Soil-Integrated Bridge System (GRS-IBS) with a full-length bridge beam resting on two GRS abutments at opposite ends subjected to earthquake motions in the longitudinal direction. This study examined the effects of different combinations of reinforcement stiffness

Deep cement mixed (DCM) soil columns have been widely utilized to improve soft soil to support embankments or seawalls. However, the influence of the time-dependent behavior of the soft soil on the performance of DCM column-supported embankments is not well understood. In this study, the finite element (FE) model was established to investigate the creep effects on settlements and load transfer mechanisms

This study focuses on the stability of stone column-supported and geosynthetic-reinforced embankments on soft soil. An upper-bound limit state plasticity failure discretization scheme (known as discontinuity layout optimization (DLO)), which determines the embankment stability without pre-assuming a slip surface, is used. The relationships between the stability of stone column-supported and geosynthetic-reinforced

This paper presents a series of model tests on geosynthetic-reinforced soil (GRS) foundations across a normal fault. The aim was to evaluate the performance of reinforced foundations as a mitigation measure for surface faulting hazards. Experimental tests modeled a 3-m thick foundation in prototype subjected to a fault displacement up to 90 cm. Test variables included the number of reinforcement layers

To understand the structural behavior of geogrid reinforced soil retaining walls (GRSW) with a deformation buffer zone (DBZ) under static loads, the model tests and the numerical simulations were conducted to obtain the wall face horizontal displacement, vertical and horizontal soil pressures, and geogrid strains. Results showed that compared with the common GRSW, the horizontal displacement of GRSW

The paper proposes a new approach to use measured data of the constant strain rate test (CRST) for analysis of consolidation by prefabricated vertical drains (PVDs). Each PVD has an influence zone that idealised as a unit cell. Consolidation behaviour of a unit cell is studied with an axisymmetric finite element (FE) model based on Biot's theory. From a CRST data, ASTM-D4186 or the back-analysis method

The hydraulic and swelling properties of a polymerized bentonite (PB), and the self-healing capacity of a geosynthetic clay liner (GCL) using the PB as the core material (PB-GCL) were investigated experimentally. Five different test liquids included of deionized water, NaCl solutions (0.1 M and 0.6 M) and CaCl2 solutions (0.1 M and 0.6 M) were used in this study. The PB exhibited a higher free swelling

This paper reports full scale experiments, under simulated heavy traffic, of geocell and EPS (expanded polystyrene) geofoam block inclusions to mitigate the pressure on, and deformation of, shallow buried, high density polyethylene (HDPE) flexible pipes while limiting surface settlement of the backfilled trench. Geocell of two pocket sizes and EPS of different widths and thickness are used. Soil surface

The seismic internal stability of reinforced, convex embankments that are three-dimensional in nature is analyzed. A limit equilibrium based three-dimensional rotational failure mechanism is adopted to calculate the required reinforcement strength to maintain the stability of convex embankments. The results are presented in the form of stability charts and the effects of various parameters on the three-dimensional

This research was conducted to investigate the shear strength at the interface between polymer concrete and asphalt concrete with geotextile as reinforcement at the interface of these two types of concrete. The samples were tested for the parameters of different surface conditions [rough and smooth], curing types [room and thermal curing], temperature effect and the impact of geotextile as reinforcement

For over fifty years, geosynthetics have been used for land reclamation of degraded areas. Several years ago for this purpose innovative geotextiles formed from meandrically arranged thick ropes were invented. The geotextiles were used for reclamation of abandoned lignite open-mine in Germany and disused gravel pit in Poland. The geotextiles were installed in abandoned mines. In next years positive

The paper examines the effects of settlement-induced downdrag on geosynthetic liner systems for a waste containment facility with steep side slopes for different design scenarios, and conducts the stability analysis of the waste mass during waste filling operations. Without the presence of a reinforcing layer above a geomembrane (GMB) liner, the liner experiences unacceptable tensile strains under

Clogging effect surrounding prefabricated vertical drains (PVDs) is a typical problem when vacuum preloading is applied to a dredged fill foundation. A large-scale model test was designed to clarify the cause and mechanism of the clogging effect, and the basic physical and mechanical parameters of the soil in the clogging zone were tracked during the test. The results demonstrated that a clogging zone

Although natural fibers can improve the strength behavior of frozen-thawed soil, the reinforcing mechanism is still not fully understood. To investigate the effects of freeze-thaw cycles on the strength of natural fiber-reinforced soil, unconfined compression tests, single-fiber pull-out tests and scanning electron microscopy (SEM) tests under 0, 3, 5, 10, 15, and 20 freeze-thaw cycles were conducted