To investigate the effect of the vertical effective and initial static shear stresses on cyclic resistance under cyclic loading with principal stress rotation, a series of cyclic direct simple shear tests were conducted on loose and dense Nakdong River sands. The results revealed that the increasing vertical effective stress (σ′v0) often decreased the cyclic resistance, and the decrease was more evident

Many railway embankments sustained extensive damage due to the tsunami triggered by the 2011 off the Pacific Coast of Tohoku Earthquake, and the operations of several railway lines were suspended for an extended period of time. Numerous studies have been conducted on enhancing the earthquake resistance of embankments, and this has led to the wide application of geosynthetic-reinforced soil (GRS) structures

Side post-grouting bored-pile foundations are widely used in geotechnical engineering. However, few studies have focused on analyzing the shear behaviour of soil and concrete while considering the grouting process. A total of 48 groups of self-developed, large-scale direct shear experiments were conducted to investigate the shear behaviour of sand-concrete interface with side-grouting, focusing on

A new strength estimation equation for cement-treated clay is proposed for marine clay with wide ranges of sand and initial water contents. The proposed equation can determine the strength of cement-treated soil by using two parameters, the ratio of the cement content to the mass of fine particles in the soil and the volumetric solid ratio excluding sand, where sand is defined as particles greater

Excavated soils and rocks, containing toxic metals and/or metalloids from geogenic sources, are usually generated in huge volumes at construction sites. And the post-excavation leaching of these toxic metals and/or metalloids with low concentrations, but higher than the environmental standards, is a major environmental concern. A sorption layer method was developed as a cost-effective countermeasure

A method is presented for using DEM to find the pore pressure, total stress, and effective stress within a granular assembly during either undrained or drained conditions, by using poroelastic principles to directly determine the pore fluid pressure. The paper considers both the saturated and quasi-saturated conditions, the latter meaning a slightly unsaturated granular material, in which isolated

This paper establishes an analytical correlation between factor of safety (FS) and reliability index β values commonly used in the design of drilled shafts in sand. This is achieved through fragility analysis of unit shaft and base resistances, calculated using finite element analysis-based capacity calculation equations, for drilled shafts. Analytical fragility curves are developed for allowable unit

Model tests are carried out in this research to investigate the dynamic behavior of multi-section cut-and-cover subway tunnels in the transverse direction by seismic motion, which has not been fully investigated up to now. Multi-section model and general single-track box-section model tunnels are installed in a soil vessel, and it is found that the sectional force corresponds to that obtained in the

Triaxial tests and numerical simulations were conducted to determine the water absorption compression of unsaturated soil. In the triaxial tests, unsaturated silt specimens under the same initial condition were prepared and the processes of different suction reduction, isotropic consolidation, and exhausted-drained shearing were applied to the specimens. The numerical simulations used a soil-water-air

Soil arching is an important phenomenon in the discussion on soil-structure interactions. Soil arching can increase the stresses exerted on a buried structure, while the absence of soil arching often results in differential surface settlement due to the difference in stiffness between the structure and the surrounding subsoil. In this investigation, model tests were conducted to relate the particle-scale

The ‘press-in’ method is a piling technique by which a pile is installed with a static jacking force while a reaction force is obtained from previously installed piles. The applicable ground conditions for this method have been significantly expanded by the ‘Rotary Cutting Press-in (RCP)’ method, whereby a vertical jacking force and a torque are applied simultaneously onto a pile with cutting teeth

On March 11, 2011, a large earthquake of Mw 9.0 shook north-eastern Japan and caused severe liquefaction-induced damage over a wide area of reclaimed lands along the coast of Tokyo Bay. Although regional mapping of the liquefaction hazard had been performed in many automounts bodies in Japan, it seems that the maps were not effectively used on all fronts of disaster-prevention management, because the

The unsaturated hydraulic conductivity function is one of the keys to solve unsaturated seepage issues, and it is difficult to be obtained via the laboratory test considering the time involved. In this study, a series of laboratory tests, include capillary rise test and downward infiltration test, were conducted to obtain the unsaturated hydraulic conductivity function of six kinds of soils varies

In engineering applications, narrow backfills are often squeezed by retaining walls. Insufficient information is available with respect to the passive earth pressure, whereas the active earth pressure of narrow backfills against retaining walls has been considerably investigated. In this study, the passive failure mechanism of a narrow cohesionless backfill under translation mode has been investigated

The objective of this study was to evaluate the effects of geostatic stresses on the compressibility and strength development of submerged geopolymer stabilized columns. In this research study, modified 1D consolidation cells were developed to replicate deep mixed columns in the field when subjected to varying stresses at various depths. Various combinations of fly ash (FA) and slag (S) precursors

The micromechanical behaviour of two sand–rubber mixture samples (i.e., a glass bead–rubber mixture sample (GB–R) and a Leighton Buzzard sand–rubber mixture sample (LBS–R)) under triaxial compression is investigated using X-ray micro-CT (μCT). Both samples contain sand and rubber grains with similar size and have a rubber content of 30% by mass. The results are compared to those of two pure sand samples

Cohesionless granular soils display stiffness anisotropy, and accurately characterizing it is essential for numerous geotechnical applications. The inherent anisotropic behaviour of geomaterials is not comprehensively understood; hence, research on the development of novel geophysical testing methods for assessing multidirectional stiffness is important. This contribution presents an innovative arrangement

The input parameters for the hardening law for the elasto-plastic constitutive model of unsaturated soils are generally fitting parameters that control the degree of hardening response and cannot easily be determined without the results of experimental tests in which the changes in suction, water content, and volume are measured or controlled. However, it is next to impossible to complete such precise

Extensive particle fracture has been noticed in projectile penetration tests. However current models for predicting projectile penetration depths do not consider particle fracture. Therefore, in order to understand the role of particle shape on single grain strength and the subsequent comminution process, single grain crushing tests on sand grains of different shapes and sizes were performed. High-resolution

Swelling deformation tests of GaoMiaoZi (GMZ01) bentonite were performed at 25, 40 60, and 90 °C in distilled water. Experimental results suggested that the maximum swelling strain of GMZ01 bentonite increased with temperature, due to the osmotic swelling dominated the swelling. The em − σv relation for compacted bentonite at a same temperature can be expressed as em=KσvD-3 (em is montmorillonite void

Piles with enlarged base have been widely employed in the civil and coastal engineering due to its high resistance to uplift. Many researchers have investigated the bearing capacity of enlarged base piles in case of small strains, but the investigations of enlarged base piles with variable geometries and large deformations are very limited. In this work, Material Point Method (MPM) is adopted to investigate

This report describes the damage and ground movements observed in the residential area of Satozuka 1-Jo, Sapporo, Japan during the 2018 Eastern Iburi Earthquake as triggered by the liquefaction of pumice sand with which a valley had been filled. The geographical setting and the on-ground and aerial reconnaissance and soil characterization results are reported, leading to a possible scenario of the

The geometry of a pile can improve the bearing capacity by changing the load transfer mechanism, such as that of X-section cast-in-place concrete piles (XCC piles). Although the geometrical effects of a single pile and pile group are investigated, the geometrical effects on piled rafts are rarely understood. This paper investigates the geometrical effects on single piles and embedded piled rafts by

In the present note, constitutive equations for air-water-solid three-phase porous materials were formulated considering thermodynamics in the context of continuum mechanics. In the formulation, the complementary energy function was used and the internal variable was adopted that manifests the inelastic strain. Then, a linear three-phase elastic model was analyzed in detail and the material parameters

The bentonite and ocean-floor clay used in hydraulic barriers for on-land and ocean waste disposal sites, respectively, act as the last defense against environmental pollution, and therefore must have high chemical resistivity and long-term stability. The primary factors that determine the hydraulic conductivity of bentonite and ocean-floor clay are the polarity and functional groups of their organic

The recycling ratio of construction sludge in Japan has gradually increased over the past 20 years. However, the increase in this ratio has become marginal. One of the main reasons for the stagnation is the alkalinity of the recycled sludge after treatment, as alkaline construction sludge can impact the environment owing to factors such as alkali leaching. Therefore, this study explored whether the

This paper describes a recently developed technique of evaluating elastic properties of geomaterials in the large size triaxial apparatus enabling to propagate elastic waves even in coarse-grained geomaterials. A flat surface transducer of 80 mm in diameter has been developed embedding four pairs of compressional and shear wave measuring piezoceramic elements. The assemblage of piezoceramics, interpretation

On 28th September 2018, an earthquake of Mw 7.5 hit the Central Sulawesi province in Indonesia. This was followed by liquefaction-induced large-scale ground flows in several areas in Palu city and its neighborhood. A significant characteristic of the ground flows at these sites was that large volume of soil slid downhill along gentle topographic gradients and travelled long distances (more than several

Physical properties of MICP-treated sands are controlled by CaCO3 distributions in pore space, which remain relatively unexplored. CaCO3 can deposit at the particles’ contact area (contact-cementing), coat sand particles (grain-coating), or create a cementation bridge between soil grains (matrix-supporting). The objectives of this paper are to determine the dominant CaCO3 distributions in pore space

Undrained cyclic responses of rubber-sand mixtures are essential for its applications in earthquake-prone areas. Hence, the present study is intended to examine the liquefaction behaviour and modeling the undrained cyclic responses of granulated rubber-sand mixtures with size of sand and granulated rubber less than 2 mm. The stress controlled undrained cyclic triaxial tests followed by undrained monotonic

Dredging activities of harbours and rivers are becoming very important in many countries all over the world and, as a consequence, the disposal of dredged sediments is a critical concern from an environmental point of view. In order to facilitate the disposal or the reuse of large volume of dredged soils, usually under-consolidated and with a high water content, an electrokinetic treatment can be adopted

Microbial Induced Calcium Carbonate Precipitation (MICP) has some disadvantages, such as low crystallization conversion rate of calcium carbonate and insufficient strength properties of tailings. In this paper, a modified method combining soft template calcium carbonate mineralization technology with microbial grouting reinforcement technology was proposed. The tailings solidification was studied with

The paper deals with the problem of the seismic stability of excavation fronts in the ancient Roman city of Pompeii, a famous UNESCO World heritage site near Napoli, Italy, buried under 4–6 m of volcanic ashes and pumices during the eruption of Mount Vesuvius in 79 AD. The attention is focused on the Insula dei Casti Amanti, a block of masonry buildings in the city centre partly excavated in recent

In geotechnical engineering, the stability of rigid footings under eccentrically inclined loads is an important issue. This is because the number of superstructures has increased and the situation of structures being subjected to eccentrically inclined loading is occurring more and more frequently. The objective of this paper was to evaluate the bearing capacity of a rigid footing on the free surface

Instability of slope soils under varying nature is one of the serious concerns in geotechnical engineering. Microbial induced carbonate precipitation (MICP) is a recently emerged, biological ground improvement technique, and that has the potential to enhance the shear strength, modify the surface conditions and promote the stability of deposits. This paper presents the experimental works conducted

Fluvial dikes are important engineering works for protecting river valleys from flooding, so the stability of them is of great importance. In this paper, we apply a two-point two-phase formulation of the Material Point Method (MPM) to investigate the dike stability problem under the action of overtopping flows. Such a method has been incorporated in the Anura3D software (www.anura3d.com). In the model

The large-scale utilization of waste materials is possible due to their comprehensive geotechnical and mineralogical characterization and their interaction behaviour with soil. No significant attempt has been made to use marble dust, a waste product resulting from the quarrying and crushing of marble, to determine its potential utilization as a geo-material. Thus, an attempt has been made here to clarify

In this paper, influence of dry-wet cycles on the damage characteristics was investigated on saline loess specimens by infiltrating sodium sulfate solution with different preset concentrations. Scanning electron microscope (SEM), triaxial shear tests, and nuclear magnetic resonance (NMR) were used to detect the changes in soil strength parameters and microstructure with dry-wet cycles and salt content

The experimental investigation reported herein aims toward the development of groutability prediction models based on the hydraulic conductivity of sand and other parameters affecting the groutability of cement suspensions. For the purposes of the present study, suspensions of three different cement types, each at four different gradations, having water to cement (W/C) ratios of 1, 2 and 3, by weight

Liquefaction effects predicted by implementing two well-known constitutive models for sandy soils are compared; i.e., the Hypoplastic soil model (HPS) and the UBCSAND model. To numerically simulate dynamic loading, the Convected Particle Domain Interpolation (CPDI) method, an advanced Material Point Method (MPM), is employed within a multi-phase framework. The numerical results from the UBCSAND model

The design and performance of the 174-m high Quxue asphalt-core rockfill dam in Sichuan Province, China, are presented. An extensive field monitoring program was implemented. During construction, the asphalt core settled more than the adjacent transition zones, but no more than 20 mm due to strong interlocking with the coarser gravel particles in the transition zones. The lateral displacements of the

Problems of ultra-soft soils, with the characteristics of high water content and very low strength, have been gradually distinguished from those of typical soft soils in recent years to address the new requirements of ocean geotechnical engineering, such as the improvement of dredged fills and hazard assessment of submarine landslides. Focusing on effects of high water content and different shear strain

This paper presents an analytical approach for predicting the nonlinear load-displacement behaviour of pile groups consisting of displacement piles in normally consolidated and lightly overconsolidated clayey soils. The effects of squeezing and remolding on the soil around the piles caused by pile installation are reflected by the soil strength and shear modulus. The nonlinear load-displacement behaviour

Since the mechanical failure of granular soils is the macro-manifestation of complex internal particle interactions, studying this relevant issue from micro-scale perspective is of fundamental importance. Acoustic Emission (AE) has become a promising approach for this purpose; however, its synthetic and validating study on granular soils with various ground conditions is far from substantive. In an

The present study considers the influence of inclined and eccentric loading on the bearing capacity of a strip footing placed on the reinforced cohesionless soil slope by using lower bound finite element limit analysis technique. The effects of other parameters such as soil friction angle, embedment depth of reinforcement layer below the footing, interface friction angle between soil and reinforcement

A number of landslides occur in the soil slopes overlying bedrock due to excavation. However, the excavation-induced deformation and failure behavior and the coupling influential mechanism of the bedrock and excavation have not been clearly elucidated, although they are essential for the stability analysis of slopes overlying bedrock under excavation conditions. In this paper, a series of centrifuge

Soil particle size distribution (PSD) is critical for assessing the potential for internal instability of sand–gravel soils, mainly because particle migration in sand–gravel soils owing to seepage forces affects almost all soil hydraulic properties during internal erosion processes. Therefore, a reliable PSD analysis is essential for revealing the mechanism of particle migration and internal instability

Free Fall Penetrometer (FFP) testing consist of a torpedo-shaped body freefalling into a soil target. The use of this type of device is becoming popular for the characterization of shallow sediments in near-shore and off-shore environments because it is a fast, versatile, and non-expensive test capable of recording acceleration and pore pressures. In recent years, the data analysis advanced considerably

In the design and construction of structures, information on the SPT N-values and the undrained shear strength is very important for investigating problems related to stability, deformation, etc. Since the shear wave velocity (S-wave velocity) is correlated with these properties, geophysical exploration methods, such as surface wave methods, which can estimate the properties densely over a wide area

Natural disasters like earthquakes and heavy rainfall events induce slope failures and other disasters. Proper determination of the water retention properties of porous mediums is necessary. The conventional Soil Water Characteristics Curve (SWCC) determination techniques are limited due to their complexity and lengthy time required. A highly accurate simple remolded and undisturbed samples SWCC determination

On 28th September 2018, an earthquake of Mw 7.5 struck Donggala Regency, Central Sulawesi, Indonesia, resulting in a catastrophic disaster and a large numbers of casualties. In this report, the results of the preliminary field investigations carried out by the authors’ team are summarized. The earthquake caused four major long-distance flow-slides on very gentle slopes of approximately 1–5% in and

Pavement structures constructed on the expansive soil subgrade experience a higher upward pressure compared to any other subgrade material. The upward pressure is caused due to high swelling and shrinkage characteristics of expansive clay soil. The present study has investigated and identified the mechanisms by which a remolded expansive soil can be modified to reduce the upward pressure and swelling

A new method to model the abrasion of granular particles using the discrete element method is demonstrated in this paper. This new, simple method is based on a classical theory of abrasive wear, relating the volume of solid lost to the frictional work at particle contacts. The modelling technique is demonstrated in simulations of railway ballast using realistically-shaped particles, which are compared

An image-based measurement system was developed to evaluate the induced local deformations of saturated sand specimens in undrained torsional shear tests. The images of specimens taken by a camera in front of a pressure chamber were noticeably distorted. To correct the errors caused by the curvature of the specimens and by the refraction of rays traveling through water, acrylic resin, and the atmosphere

This paper presents the effects of inherent anisotropy on the shear strength and shear modulus of both saturated and unsaturated sands. Several triaxial compression tests were performed using Toyoura sand with different contents of mica: 0%, 1%, 2.5%, 5%, and 10%. Specimens with various deposition angles α were prepared using the air pluviation (AP) and dry vibration (DV) methods. The shear strength

Shaft resistance is the major source of bearing capacity and has a critical effect on settlement of prebored and precast pile (PPP). In this paper, the load-transfer behavior and shaft resistance of steel pipe PPP was observed based on real scale pile loading tests. The main focus was on determining the load transfer mechanism and establishing a framework on shaft behavior of steel pipe PPPs. 10 cases

This study investigated the soil adsorption characteristics against gaseous mercury. A method for the adsorption tests using gaseous mercury was established, and the distribution coefficients for silica sand, decomposed granite soil, mordenite, and calcium bentonite were evaluated. Glass vials with polytetrafluoroethylene (PTFE) plugs were suitable for the adsorption tests as gaseous mercury did not

Discrete element method simulations are used to investigate the effects of particle shape on the plastic behaviour of sand. This is achieved by using four different shapes of crushable particles. The behaviours of the different particles when subjected to isotropic compression, triaxial shearing, and a range of stress path tests are compared, revealing the important role of particle shape on key aspects

This paper presents an experimental study on the effect of polypropylene fibres on the yielding behaviour of cement-admixed soft marine clay. A range of mix ratios is investigated, with the cement content spanning from 20% to 100%. The unconfined compression strength is first examined, followed by isotropic compression and subsequently shearing in triaxial stress conditions. These experimental results