The tensile strength of gravelly soil plays a decisive role in the formation or initiation of longitudinal cracks or hydraulic fracturing in the core of earth and rockfill dams. For this study, a series of uniaxial tensile tests and consolidated drained triaxial shear tests was carried out to study the relationships between the tensile strength and shear strength indexes of gravelly soils with gravel

The design load of a loessal tunnel is usually calculated using the conventional Mohr-Coulomb strength criterion, which ignores the structural strength of loess and provides inaccurate calculation results. The present paper therefore proposes a bilinear strength criterion considering the structural strength characteristics of loess determined in a triaxial shear experiment. Then, using the new strength

The present article considers the possibility of using an unvented underfloor space enclosed with heat-insulated panels for pile-supported, low-rise buildings in permafrost areas. A long-term, in-situ experiment revealed a pattern of changes occurring over time in the ambient air temperature, the temperature in the underfloor space, as well as the depthwise temperature changes of the foundation-bed

The article presents a new method for determining the bearing capacity of augercast tapered piles in clayey soils by considering the various factors such as the level of external load, the sequence of operations in the installation of piles, and variations in the physical and mechanical characteristics of soils in the pile space that are responsible for effective performance of piles. This method is

A new method for treatment of dredger fill was proposed to address its low bearing capacity, high consolidation cost, and long treatment duration. In this method, cotton straw is used as both the draining and reinforcement material. Specifically, cotton straw bundles are driven into the dredged soil and vacuum preloading is then performed. Subsequently, environmentally friendly grout is poured into

In this study, the effects of different shear rates during direct shear tests on variations in the strength characteristics were investigated for the sand samples of various particle size distribution. Direct shear tests were carried out at nine different shear rates ranging from 0.05 to 5 mm/min under normal stresses of 54.5, 109, and 218 kPa. Both sample groups were tested under a condition of defined

The present article investigates the possibility of maintaining the condition of foundation-bed soils of buildings constructed in permafrost zones using vertical seasonal cooling mechanisms and effective horizontal thermal insulation to obviate the need to construct a separate cold underfloor space. The research was carried out using existing buildings in the city of Mirny in the Sakha Republic as

This paper focuses on the influence of joints on seepage capacity of a soil mass, the water infiltration range, the area of the wet zone, and water content distributions. Tests were performed using a self-designed seepage device to determine the hydraulic conductivity of loess samples with natural joints. The test results indicate that joints greatly improve the seepage capacity of a soil mass; the

The variational limit equilibrium method is adopted to calculate the active earth pressure with and without tension cracks appearing. According to static equilibrium equations of sliding soil, a functional extreme-value isoperimetric model of cohesive soil is deduced in the general case of an inclined wall, sloping backfill, and uniform surcharge on the backfill surface. The active earth pressure is

The presence of a gas component is an important feature of the frozen soils structure, which is currently practically not studied by laboratory methods during engineering surveys. To assess the gas content and dynamics of gas emission from frozen soils, the authors have developed equipment and a technique for triaxial and shear testing of samples at different temperatures and stress states. As a result

Anionic polyacrylamide (APAM) and quicklime are used to improve vacuum preloading of waste slurry in Shanghai, China. To investigate the influence of these reagents on waste slurry sediment consolidation, tests on laboratory-scale models with and without the reagents were conducted and the results analyzed. Sediment settling was recorded and used to calculate the water content changes during vacuum

An effective tool for studying the behavior of the skin friction of piles in a rock formation is through a numerical analysis. Four pile load experiments were conducted on hard limestone rock samples to describe the behavior of the load transfer solely through the skin friction on reinforced concrete piles with different diameters and lengths. Finite element analysis was performed using PLAXIS 3D software

The article discusses problems of engineering investigations and the structure of gas-protection objects in territories with gas-generating soil.

This study proposes a general methodology for an elasto-plastic model for unsaturated soil and proves its feasibility through a set of experimental calculations. The method can be used to estimate the stability and optimize the size of retaining walls on unsaturated soil.

The article discusses modern methods of the injection stabilization of rocky and dispersed soils used in industrial, civil, and hydraulic engineering construction, as well as in repair and restoration works.

This study aimed to systematically explore the meso-structure multi-phase volume deformation mechanism and the deformation characteristics relationships of EPS (expanded polystyrene sheet) silt lightweight soil between macro- and meso-structure of the complex composition silt lightweight soil under cyclic loading. A series of modified consolidation tests and numerical simulation of the typical mix

The failure of dikes is mostly caused by the development of piping. Whether or not piping erosion develops is mainly determined by the critical hydraulic gradient. In this paper, a multi-particle model for the critical hydraulic gradient of dike piping is derived. The model is based on the Terzaghi formula, and considers particle size distribution characteristics and the interaction between the sand

On the basis of the first proposed soil layer composite ratio, a single comprehensive index calculation model of geological characteristics in the Caoqiao Tunnel, China, is established using AHP (Analytic Hierarchy Process) and WAM (weighted average method). A model of geological characteristics is then used to discriminate a number of geologically characteristic groups. The results show that the curve

A brief overview on the development of theory and practice in pile foundation engineering is presented, including the main construction solutions for piles and pile foundations, methods for their vertical and horizontal loading calculation, as well as trends in the development of principles informing their design.

Based on the discovery of the "natural orange soil layer" in the wall foundation of the Ming Great Wall in Huangzhong County, Xining City, northwest China, this paper reveals the mechanism behind the barrier effect of this layer on the salinity deterioration through the combination of qualitative judgment and quantitative testing. Based on this mechanism, the conventional lime soil was improved by

We conducted a centrifugal model test to investigate the deformation and failure mode of a geogrid-reinforced and pile-supported (GRPS) embankment. The embankment filling was simulated using the incremental acceleration method, and the surcharge was subsequently applied using an inflatable airbag on the embankment. By installing different types of instruments, the displacement of the soil, the axial

The porosity, shear modulus, and dynamic permeability coefficient of saturated inhomogeneous soil changes continuously with soil depth and is described according to the power function. The governing equation of two-dimensional dynamic was established based on the theory of Biot saturated porous media to solve the governing equation by Fourier series and obtain the displacement of each point steady-state

The present article proposes a mathematical model for calculating the temperature regime of foundation-bed soils for an industrial building, considering the operation of horizontal seasonal cooling mechanisms under challenging geocryological conditions. The model takes the following points into account: air temperature in the building, atmospheric air temperature, depth of placement, number of seasonal

Through CT scanning, digital image processing, reverse engineering reconstruction, and 3D meshing, the numerical model of the mixed soil was established. On this basis, a numerical simulation of the triaxial testing was carried out. The movement of the 70 gravels was monitored and analyzed based on the proposed geometric feature point method (GFPM). The interaction between the gravels and soil during

The article presents the results of studies on soil shear strength at the interface of structures made of various materials. The authors propose procedures for performing direct shear tests at the soil-structure interface and determining the interface shear parameters according to cone penetration data. Recommendations for considering the type of construction material in soil-structure interaction

A finite element model is presented which simulates the tunnel construction process, and deformation and stress characteristics, in the surrounding rock during its operation stage. The pore water pressure and distribution law of leakage in the surrounding rock are calculated by considering the effect of groundwater. The results show that during the process of excavation, the surrounding rock undergoes

The article discusses the prediction of the bearing capacity of driven piles on argillite-like clays and sandstones of the Permian age. The methodology was developed and field tests of piles were performed; the aspects of the formation of the bearing capacity of piles are revealed; and recommendations are formulated for the design of foundations on bases composed of of argillite-like clays and sandstones

The effects of acoustic emission (AE) in soils during freezing and thawing under cyclic thermal and quasi-static mechanical loading have been studied. The composition and characteristics of the developed instrumentation set are presented. The informative AE parameters and primary data processing approaches were justified. The acoustic emission patterns of soil material behavior under the variable thermobaric

Hysteretic devices are essential for base-isolated buildings to control the deformation in the isolation system and to dissipate the earthquake-induced energy. U-shaped steel dampers dissipate energy through plastic deformation of specially designed steel elements. This paper investigates the performance of U-shaped steel dampers for the seismic isolation system as well as comparison with lead rubber

This paper explored the impacts of montmorillonite and kaolinite (M-K) ratio as well as consolidation time on small-strain shear modulus and damping ratio of clay soils. A resonant column device was applied to the free vibration column tests. At small shear strain of 0.001%, the shear modulus and damping ratio increased by 57% and 105% respectively when the M-K ratio rose from 0.25 to 4. At higher

Two reinforced soil retaining walls with full-height rigid facing were modeled in a centrifuge. One model wall was constructed on a sand foundation with a relative density of 90%, and the other was constructed on a clay foundation with a smaller compression modulus. The model walls were both constructed in three stages, and the reinforcement strain, vertical earth pressure at the base of the facing

To study the soil-structure dynamic interaction, field-simulated ground motion tests of a 15-storey reinforced concrete frame structure are designed and performed. The response records of the structure and ground motion near the foundation are processed and analyzed. The fixed-base natural frequencies and modal damping ratios of the superstructure are determined and compared with the results obtained

We studied the relationship of humidifying deformation and water immersion content from the unsaturated to the saturated states and analyzed the factors influencing humidifying deformation in water immersion of compacted loess. Humidification axial strain was mainly affected by deviatoric stress, and the influence was significant. We studied the deformation characteristics of compacted loess under

The present paper substantiates the relevance of the scientific and technical task of designing effective helical pile constructions under conditions of insufficient development of existing standards. An adapted computer design technique was developed on the basis of comparison and analysis of the calculation results and field tests for multi-helix helical piles in cohesive and cohesionless soils using

We performed a series of small-scale physical modeling tests on two types of multiple ball-shaped nodular underreamed anchors under vertical uplift loading conditions using transparent soil and particle image velocimetry. Three sets of numerical investigations were also carried out to study the effect of anchor structure parameters on uplift bearing capacity. The results show that a larger ball diameter

The paper discusses specifics of R&D support of designing and constructing the foundations of the football (soccer) stadium in Rostov-on-the Don, as well as results of geotechnical monitoring during construction and operation.

The paper discusses the authors-developed technology for constructing offshore waterproof steel sheet pile cofferdams for creating artificial islands. The proposed technology enables increased efficiency and reduced work completion times.

The effectiveness of applying granular foam glass ceramics to protect a roadbase from seasonal freezing is demonstrated. Observational results of the base temperature regime are presented along with a comparative assessment of risk zones characterizing the depth of freezing and possibility of intense frost heaving.

It is necessary to consider the influence of the actual soil voltage distribution when establishing the consolidation equation to more realistically reflect the soil consolidation conditions during the vacuum preloading and electroosmosis process. The distribution of the soil voltage is analyzed by integrating previous results with independent experimental findings. The equation for the dissipation

There are many factors affecting the stability of cut and fill multistage slopes, and these factors exert different degrees of influence on slope stability. The grey incidence analysis method can be used to evaluate the sensitivity of these factors. To overcome the shortcomings of the grey incidence analysis model used in previous sensitivity analysis studies on the factors influencing slope stability

In order to investigate the influence of granulometric and material composition on rheology, in this study an improved direct shear creep apparatus is used to conduct shear rheological tests on sandy soil samples of different granulometric compositions and water contents. Creep curves for different shear load levels, as are the average viscosity coefficients of soils based on the experimental data

In this study the vertical swelling pressure in disturbed expansive soil was evaluated under constant-volume hydration swelling tests. The volume change during inundation was observed under two conditions: constant vertical stress at inundation and constant volume. A swelling stress-strain relationship model of compacted expansive soil is established under a one-dimensional axial load, which is related

We investigated the strength and deformation characteristics of undisturbed unsaturated loess under different moisture content conditions. The results showed that the deviatoric stress intensity increases with the increase of confining pressure at the same moisture content and decreases with increasing moisture content at the same confining pressure. Moreover, the matric suction and the shear strength

Calculation of the bearing capability of piles in a pile field, based on the calculations and tests of single piles, taking into account their interaction with each other through the soil ground, is proposed. Differences in the operation of a single pile from a pile in a group are shown. The main attention is paid to determining the dependence of the ultimate resistance of piles on the parameters of

The aspects of determining the moduli of unloading and reloading of dispersed soils were considered. Sample tests involving triaxial compression devices showed that these parameters depend on the stress-strain state. The ratios between the primary loading and reloading moduli accepted in design practice were significantly underestimated, which led to errors in determining the settlement of structures

To explore the factors affecting the shear strength of compacted loess, direct shear tests and compression tests under different moisture contents and compaction were conducted. The results show that the angle of internal friction and the cohesion of the soil depend on the moisture content and compaction. The influence of the moisture content is more significant than that of the compaction. The relationship

The data of the uniaxial compression tests of limestone samples with the registration of the strain gauge data and parameters of acoustic emission and thermoradiation signals are presented. A joint analysis of the experimental time dependencies of the variations of mechanical and physical parameters is performed. The identification methods of the deformation stages of the test samples are considered

The problem of improving foundation bases in strongly deformable and structurally unstable soils is examined. A design is proposed for a sand cushion reinforced with horizontal geosynthetic elements. The results of the operation of the proposed structure with basal soil as well as approaches to determining the maximum resistance force and the deformation of a base improved by such a structure are presented

This paper discusses the comparative study of design moments for pile cap with conventional methods and finite element analysis. If a detailed finite element analysis is adopted, flexibility of the pile cap is considered. When a pile cap is designed by truss analogy, 80% of the tension reinforcement is concentrated in the region where the cap is supported on piles and at the column, which depends on

Modern theoretical and technological trends in the development of static penetration tests are investigated.

Design calculations of the modulus of deformation of non-dilatant argillaceous (clay) soil based on the theoretical solution for a head resistance of a sounding device are presented. The results of calculations for the data of static sounding are compared with those taken as standards of the Russian Federation; a completely satisfactory correspondence is shown.

Given the complexity of the tests and the ambiguity of the experimental and calculated estimates of the pile load capacity of collapsible soils, a method for determining it is proposed on the basis of the results of tests of soils with natural moisture content without insulation of piles within the collapsible thickness. The method decreases the cost and time of testing and increases the accuracy of

This paper presents an experimental investigation of the deformation characteristics of salt rock under different loading conditions. A simple empirical model for the evolution of fatigue deformation is proposed. The results clearly show that the fatigue deformation is strongly dependent on the applied frequency, stress, and loading rate. The higher the loading frequency, loading rate, and stress amplitude