The triaxial compression tests of multi-layered rock mass samples prepared from the laboratory were carried out by using the rock servo-controlled triaxial rheological test system, and the mechanical properties of multi-layered rock mass are studied. According to the test results, the deformation characteristics and failure modes of multi-layered rock mass samples are analysed. The relationship between

The study of ultimate bearing capacity (UBC) of uplift piles in combined soil and rock mass is of great significance in engineering. In order to study the UBC of uplift piles in combined soil and rock mass, in situ uplift tests in practical engineering were conducted, and a suitable Flac3D numerical simulation model was established by combining with geological conditions in engineering and in situ

This study explores the effect of Guar gum as an eco-friendly additive on concrete mechanical characteristics. In the first stage, the slump and relative humidity tests were carried out for the fresh mortar, and tensile and compressive strengths were then determined for fifteen different mixture designs with two different curing times. Further, an exponential correlation was obtained between the ultrasonic

The article examines the fringe effects of a two-rod capacitor inserted in a medium like a soil, due to its finite height h and presence of leads to measurement unit. The effects modify the coefficient g of conversion from probe capacitance to medium permittivity. The change of g from its expression gth without effects is determined in function of probe and lead dimensions through numerical simulations

The addition of Electric Arc Furnace Dust (EAFD) in concrete is a good solution to encapsulate its potential toxic elements and to contribute to the valorisation of industrial wastes. This paper investigates the feasibility of using EAFD as an addition to concrete production. Four experimental mixes have been produced (one of traditional concrete and three introducing a 5, 10 and 15% of EAFD per cement

This paper highlights the effect of non-plastic fines on sand matrix by performing a series of undrained triaxial tests. The silty sand specimens were reclaimed by moist tamping method and two distinct density indexes of sand matrix were selected: IDmat=0.00 (<0.15) for very loose state and IDmat=0.50 (>0.40) for medium-dense state. The addition of non-plastic fines to the host sand matrix makes the

Conventional landslide drainage methods always seem to lack a long-term and efficient drainage capacity. Thus, it is necessary to develop a new drainage method that does not have these disadvantages. In this study, a new, self-starting drainage method is proposed based on the results of tests that were conducted with a physical model. The principle involved is that the drainage starts automatically

The primary objective of this article is to present a case study of valley deformation in high arch dam and its relationship with water level fluctuations. Data of displacement versus reservoir level monitored over a five-year period are used to determine possible relationship between displacement and reservoir level. It is found that valley deformations are closely related to the filling-drawdown

During the operation period of the high arch dam in some canyon area, the valley deformation is obvious under complex geological environment. Several possible factors may influence this phenomenon. In this article, influencing factors are considered from the aspects of precipitation, temperature, reservoir water level elevation and the rate of reservoir water level variation. Two machine learning methods

This article presents a novel automatic PSO-based back analysis method for mechanical parameters of block discrete element method. Incorporating particle swarm optimization (PSO) algorithm and recursive algorithm, a parameter back-analysis program is developed. Two cases, a laboratory test of columnar jointed rock mass and a typical landslide, are implemented for validation. The results show that the

A triaxial unloading mechanical test is conducted on sandstone considering different initial confining pressures and unloading rates under the effect of hydraulic coupling. The energy evolution of sandstone unloading failure is studied, and the influences of the initial confining pressure and unloading rate on the deformation characteristics and permeability evolution of sandstone are discussed. It

Permeability and porosity are two crucial properties related to underground gas storage. This research investigates the permeability and porosity evolution of a Vosges sandstone under different stress paths. Under hydrostatic stress, the influence of irreversible deformation on permeability is more significant than on porosity. The permeability is more sensible to confining pressure than porosity.

Uncertainties of geotechnical parameters in landslide engineering mainly arise from their spatial variabilities, measuring error and inaccurate constitutive model. Interval limit equilibrium method (ILEM) is used to analyse the stability of landslides with uncertain geotechnical parameters. However, the method suffers from the issue of overestimation in the calculation of the safety factor (FS) interval

This article investigates the passive earth pressure through the laboratory-scale test conducted on a 600 mm rigid retaining wall when rotated about its base. An advanced digital image processing technique such particle image velocimetry (PIV) is employed for monitoring of slip plane propagation. The test results show a nonlinear distribution of earth pressure and the failure occurs at a maximum top

The current study aims at seismic analysis of damaged concrete gravity dams subjected to aftershocks loading of earthquake. Dams’ sliding behaviour is also discussed to shed light on the issue. For the purpose of the study, a cracked concrete gravity dam was modelled, and zero thickness contact elements were used to model the contact between the main body and the separated damaged parts of the dam

The Malogne Phosphatic chalk quarry was developed by the rooms and pillars mining method within an area of 67 ha. The site is partially flooded and located in close proximity to important infrastructure as railway, highway, and residential houses. During and after its exploitation several significant ground collapses were registered. The last one, with an area of 1.2 ha and 3 m amplitude occurred in

On 10th October and 3rd November 2018, two landslides and the consecutive twice blockage of the Jinsha River led to sharp fluctuations of the upstream water level. These two events have caused numerous bank failures along the Ouqu River in the upper reaches. In this paper, a numerical model coupling the seepage and stability analyses was established, which was able to capture the fundamental behavior

Pre-existing joints within a rock mass has a significant effect on the hydro-mechanical properties of the rock mass. The study investigates the hydro-mechanical properties of rock-like materials with intermittent joints under different confining and hydraulic pressures. Cylindrical specimens containing two sets of parallel pre-existing joints were prepared, and the hydro-mechanical experiments under

During fluid injection tests performed inside the clay-rich Tournemire fault zone, the monitored fault displacement exhibited limited amplitudes whereas a sharp increase of the permeability occurred as the fluid pressure reached a threshold value. The injected fluid channeled through the fractured zone or at the interface between the host rock and the fault core over decameter distances without triggering

The mechanism of toppling deformation and failure is important in the stability analysis of anti-dip layered rock slopes, especially in a complex hydrogeological environment. In this paper, the flexural failure model is proposed for describing the mechanical behavior of toppling rock slope using the cantilever beam theory. A method for safety evaluation, considering the action of hydrodynamic force

Pile foundations are usually subjected to cyclic loading which could possibly causes a significant degradation of the friction mobilised along the pile shaft. Most of the experimental studies devoted to analysing the behaviour of the pile-soil interfaces under cyclic loading tests are performed at a few hundred of cycles. However, a large number of cycles of the order of hundreds of thousands may cause

In previous experimental studies, the detailed amount of particle breakage under impact loading cannot be obtained due to the coexistence of fragments and unbroken grains in multi-sized sands. In this study, a series of impact loading tests were carried out to three kinds of coral sands to explore the detailed particle breakage in multi-sized sand samples. Before impact loading tests, coral sands in

Ultra-high-performance concrete (UHPC) results from the mixture of several constituents, leading to a highly complex material in both, fresh and hardened state. The higher number of constituents, together with a higher number of possible combinations, relative proportioning and characteristics, makes the behavior of this type of concrete more difficult to predict. The objective of the research is to

This study evaluates the performance of electrokinetic (EK) treatment to improve the engineering properties of soft soils. Laboratory tests were conducted using ionic solutions of calcium chloride, CaCl2 and sodium carbonate, Na2CO3. Atterberg limits, unconfined compression, electrochemical, thermal, and microscopic tests were performed in terms of treatment duration, anode-to-cathode distances, and

This paper explores the deformation behaviour of 1# toppling rock slope, located on the right bank of the Lancang River upstream of Huangdeng Hydropower Station in China. Field monitoring data show that the surficial and deep displacements of the toppling rock slope increase greatly during the second stage of the impoundment period. The deformation of the toppling rock slope in the lower part is generally

To enrich understanding of how fluid flows through the natural filled jointed rock, the permeability experiments of the natural filled jointed dacite rock under repeated loading and unloading conditions are carried out. Experimental results show that the response of permeability of filled jointed dacite rock to confining pressure under repeated loading and unloading conditions is considered as porous

The triaxial compression tests under different hydraulic pressures and low confining pressure were carried out to study the hydraulic pressure effect on the mechanical properties and permeabilities of layered rock mass. In general, the results show that the increase of hydraulic pressure reduces the peak strength of layered rock mass and the layer structure changes the mechanical properties of rock

During the reservoir filling of many high arch dams, it was observed that the valley slopes on both sides deformed towards the river. The measured value of valley narrowing lateral deformation (VNLD) reached 89.54 mm by October 2018. This rare phenomenon contradicts the traditional experience of dam engineering and lacks a convincing explanation. An arch dam project in China is selected as a case study

Flow-structure interaction has raised significant attention among geotechnical community because it is important for prevention of high-speed flowing geo-disasters. Physical modeling serves as a fundamental tool with which to reveal the disaster-causing mechanism, but such modeling is challenging to perform especially in 1 g model tests because of the complex rheology of flows, transient nature of

In this article, the mechanical properties and material characterisation of graphite tailings concrete, in which graphite tailings are replaced as sand were investigated. The results showed that the concentration of graphite tailings has influence on the comprehensive performance of concrete. Simultaneously, the graphite tailings have an important improvement on reducing the mesostructure distribution

The passivation behaviour of passive films on the surface of reinforcing steels exposed to alkaline solutions was investigated. Two types of reinforcing steels (low-carbon steel and low-alloy steel) with different surface conditions (polished steel with uniform surface and as-received ribbed surface with mill scale) were chosen to compare their passivation capability. Moreover, steels were exposed

Soil filters that are commonly used to stabilize base soils in infrastructures are gradually prone to microparticle accumulation. Sequestration and accumulation of suspended solid particles in fluid on the media surfaces of the filter lead to porosity and permeability reduction through the porous medium and cause physical clogging. This reduces hydraulic conductivity and eventually filters drainage

In this article, a novel artificial intelligence method, i.e. random forest (RF), was adopted as a computer-aided tool to predict the vertical displacement of several pile-supported bridge piers above two overlapped earth-pressure-balanced machine (EPBM) tunnels. Naive Bayes theory was introduced for the statistical analysis of the results predicted by the RF method to address the operational variables

Storage basins, check dams, barriers and other control works are often used to reduce threats and damage from flow-like mass movements. This paper deals with the effectiveness of two storage basins of the Italian Alps against debris flows followed by a flash flood induced by short heavy rainfall in 2009. Referring to detailed field data, the propagation of flows and their interaction with the control

As the actual jointed rock mass often does not behave elastically, its deformation modulus is typically used in practical engineering. In this study, an analytical equation for characterizing the damage variable of in-situ rock mass was investigated. This equation is primarily based on the P-wave propagation velocity, and its simplified form, which only considers the deterioration of the P-wave propagation

The time dependency of tunnelling results mainly from the rheological properties of the rock mass, the sequential excavation and the construction process of liner. This study focuses on the construction of lined circular tunnels in viscoelastic rock mass subjected to non-hydrostatic far-field stresses. The analytical solutions of stress and displacement for both rock mass and liner are developed. In

The bearing capacity of shallow foundations on rocks under inclined and eccentric loads is investigated using the kinematic approach of limit analysis theory. The study focuses on evaluating the reduction of bearing capacity induced by the eccentricity and the inclination of the load with respect to the vertical direction. The generalized Hoek and Brown criterion is adopted to describe the strength

The cohesion c and the internal friction angle φ (hereinafter referred to as the c-φ parameters) are the basic parameters that characterise rock strength. This paper proposes a method that makes use of digital core drilling in the prediction of rock’s c-φ parameters. Based on slip line theory, this paper develops a core drilling rock cutting mechanical model and obtains the quantitative relationship

Due to the complexity of the hydro-mechanical behaviour of soils subjected to internal erosion, a high number of parameters are usually required for the erosion models and the constitutive models. This aspect makes it difficult to determine by trial-error their relevant values from laboratory tests. To address this issue, an efficient optimisation-based procedure for identifying the parameters of a

Many models have been developed for landslide displacement prediction, but owing to complex landslide-formation mechanisms and landslide-inducing factors, such models have different prediction accuracies. Thus, landslide displacement prediction remains a popular but difficult topic of research. In this paper, a landslide prediction model is proposed by combining extreme learning machine (ELM) and random

With the fast-developing bioengineering techniques in recent decades, researchers have started to try to apply bio-techniques to geotechnical engineering. Microbial induced calcite precipitation (MICP) has known a mushroom growth, due to its sustainability and feasibility. In order to achieve lower cost, higher efficiency and higher operational feasibility, many studies have been carried out to optimise

The present study is aimed at investigating the change in surface morphology, hydraulic behaviour and sorption capability of two locally available Indian bentonites in the presence of different lead (Pb2+) concentrations. FESEM, FTIR, and EDX studies were conducted to analyse the change in surface morphology, alteration in FTIR pattern and decrease in exchangeable cation in both the bentonites before

A large scale shaking table test was carried out to study the failure modes of the slope stabilized by frame beam with prestressed anchors. Based on the Hilbert–Huang Transform (HHT), the damage identification analysis was performed by using the marginal spectrum obtained from the acceleration responses. The results from the tests show that the seismic damage of the slope stabilized by the frame beam

Textile reinforced cementitious composites are commonly used as structural or non-structural elements having superior properties. These composites are a combination of various technical textile and fine-grained matrix material. In this study, alkali resistance (AR) Glass mesh, Basalt mesh and polyvinylalcohol (PVA) weave textiles and polymer modified cementitious matrices were used in the production

The chemical corrosion has a significant degradation effect on the mechanical properties of non-persistently jointed rocks. In order to improve their physical and mechanical properties, the modification test was carried out by using silicone immersion and resin filling in the pre-existing joint with different geometries after chemical corrosion. This modification influence on the mechanical properties

According to the evidence of numerous advantages of earthen buildings, there is an increasing interest to study adobe elements for sustainable development. This paper presents experimental investigation alongside numerical simulation of several adobe elements under compression, direct tension, three-point bending and indirect shear tests to have a better understanding of their basic mechanical properties

The flexural behaviour of steel fibres reinforced concrete (SFRC) beams is investigated using digital image correlation (DIC) technique. The deflection and curvature of the tested RC beams have been analysed by DIC technique. The experimental results in terms of deflection and other results found in the literature are compared against the predicted values using the design codes (ACI318, Eurocode 2

Owing to structural and environmental reasons, the use of pozzolans as cementitious materials in several kinds of concrete has increased in the last decade. The objectives of this experimental study were to examine the effect of weather conditions, winter and spring, on curing metakaolin-based pervious concrete; investigate the impact of various eco-friendly fine aggregates for improving the structural

The critical velocity of soil particle reduces under the influence of seepage effect, thereby affecting the dam breaching process of non-cohesive homogeneous dam. In this paper, the formula of the critical velocity considering the seepage force was deduced by analysing the soil particles force on the slope. A dam breach model of the non-cohesive homogeneous dam was established to study the effect of

Fiber reinforced mineral matrix composites have been used increasingly, through the last few decades, to build lightweight and thin structures, and to repair or strengthen old and damaged buildings. However, the reinforcing efficiency of these composites is limited by the low penetrability of cement particles into the space between the inner filaments, leading to a decrease in the composite’s mechanical

Reasonable evaluation and prediction of squeezing condition to avoid large deformation disaster in tunnels have been an important research issue. In order to accurately and rapidly predict the large deformation under complex geological conditions, this paper proposes a classification and prediction method for quick identification of large deformation in tunnel construction stage in a case study of

An overview about the behaviour of two soft soils (Kaolin Silt and Lower Rhine Clay) under monotonic as well as cyclic loading is presented. Thereby it is shown that especially Kaolin possesses an inherent anisotropy, which can be described by a transformation and through scaling of the tangential stiffness tensor. The AVISA model is enhanced and shows accurate reproduction of the behaviour of these

This paper examines the internal rectangular loading problems for an elastic halfspace where the shear modulus varies exponentially or linearly and the Poisson’s ratio keeps constant or varies linearly with depth. The numerical method is developed through applying the fundamental solution of layered elastic solids and integrating numerically it over the loading area. The adaptive integration of the

Under the long-term effect of high stress, the stability problem caused by the time-dependent deformation of brittle surrounding rock in deep engineering is becoming more and more prominent. The accurate description of the effectiveness of brittle rock is an important basis for the prediction of mechanical response and the stability evaluation of surrounding rock in deep engineering. To describe the

Under the conditions of HT-HP, the subsea pipelines transmitting oil and gas in deep sea water often experience lateral buckling due to the accumulation of axial force. The pipe–soil interaction is one of the most important factors during the lateral buckling. In order to understand the pipe–soil interaction deeply, a series of tests about the pipe–soil interaction with different initial pipe embedments

The dilatancy equation plays a significant role in establishing an elastoplastic constitutive model for soils. The rockfills will show strain-softening or strain-hardening behaviour according to the testing confining pressure and/or initial void ratio. Therefore, a new dilatancy equation for rockfill materials incorporating strain hardening and strain softening was studied. A series of triaxial compression

Shake table tests were conducted on three 1:3 reduced scale two-story RC frames having weaker beam-column joints. The models were subjected to multi-levels input acceleration time histories to understand the seismic behaviour of test models. The models incurred severe damages in beam-column joint panels, forming shear hinging in joint panels, and were found in the incipient collapse state under input

Ground surface settlement (GSS) is one of the major concerns in design and construction of a deep excavation. This paper proposes an analytical approach for the prediction of GSS induced by a braced deep excavation. Considering wall deformation and stress release, the problem investigated is formulated as a system of two second-order partial differential equations (Lame equations) with mixed boundary

A sustainable Self-Compacting Concrete (SCC) was proposed by replacing natural aggregates with recycled coarse aggregates (RCAs) and cement with supplementary cementitious materials (SCMs). A total of 23 SCC mixes, including binary, ternary and quaternary mixes were prepared with three water to binder ratios (0.35, 0.40, and 0.45) and two RCA replacement levels (50%, 100%) as well as two SCM replacement

The aim of this work is to compare two methods of incorporation of concrete recycled coarse aggregate (CRCA) in the concrete mixture: at the beginning and at the end of the mixing stage. Concrete mixtures with 0% and 50% of CRCA were developed, with three water/cement (w/c) ratios. Slump loss and electrical resistivity were measured in the fresh state. Compressive strength and water absorption by capillarity