The field bearing plate method test is the most commonly used method to determine rock mass deformation parameters. Currently, due to the effect of the applied test stress, the difference between the rheological model curve and test curve can be significant, namely the model cannot reflect the effect of the applied stress. In this study, a seven-component viscoelastic combination model that considers

Due to long-term coupling of ground stress and water pressure during operation processes, lining concrete will experience different degrees of cracking and spalling, which seriously affect the safety of tunnels during service. In this paper, lining concrete seepage tests under different confining pressures are performed; the mechanical properties and acoustic emission (AE) responses during the loading

We present a strong nonlocal hydromechanical model formulated based on state-based peridynamics for simulating strain localisation in unsaturated geomaterials. The governing equations are integro-differential equations in which length scales are assumed for both the skeleton deformation and pore fluid flow. Recently proposed hydromechanical correspondence principle is adopted to implement the classical

The Meuse/Haute-Marne underground research laboratory was built in the Callovo–Oxfordian (COx) clay formation for the purpose of assessing the feasibility and safety of a deep geological formation to host an industrial radioactive waste repository (Cigéo project) in France. Some observations related to the drifts oriented in the direction of the major horizontal stress remain to be theoretically and

In order to study the impact of internal erosion at the scale of an engineering structure, a hydro-mechanical continuous modelling approach considering suffusion is needed. It requires a relevant mechanical model for granular soils considering the f c -dependency ( f c : fines content) and a hydraulic model for suffusion to control the changes in the fines content. To this purpose, the mechanical models

Due to the rugged topology, bridges in Western China often contain piers over 40-m height. The seismic responses of these tall pier bridges are usually estimated using nonlinear time history analysis (NTHA) procedure, which is rigorous but time consuming and computational demanding when plastic performance is involved. This paper modified a procedure previously proposed estimating nonlinear seismic

The geotechnical properties, chemical reaction mechanisms, and microstructure evolution of alkali-activated fly-ash-stabilised construction and demolition waste (C&D) and the main components recycled concrete aggregate (RCA) and clay brick (CB) were investigated in this study. The alkali activator was a composite solution of sodium hydroxide and water glass. XRD, FTIR, SEM, and UCS testing methods

To explore the microscopic mechanism underpinning the dynamic characteristics of saturated loess, dynamic triaxial tests were conducted on saturated loess in Xianyang City, China. The tests were performed under dynamic loads of different waveforms, confining pressures, frequencies and amplitudes. Under each dynamic load, the test included two states: one stopped after 12 loading cycles, and the other

In this research, three- dimension finite difference method was applied to simulate the tunnel excavation by earth pressure balance (EPB) boring machine of Tehran Metro Line 7 tunnel in Iran. Sensitivity analysis and parameter identification was carried out by Morris Elementary Effect method to evaluate the relative sensitivity of model for each input parameter. Then, artificial neural network (ANN)

In this study, the effects of polypropylene fibre content and length on the mechanical properties of municipal solid waste incineration (MSWI) bottom-ash-mixed (BA-mixed) clay soil were investigated through triaxial tests. By varying the fibre length and content, the stress-strain relationship and strength characteristics of polypropylene fibre-reinforced soil were analysed under different confining

The effects of elevated temperatures on concrete containing glass waste are investigated. Addition of 15% waste glass powder by weight of cement is performed to obtain glassy concrete (GC). This study provides several recommendations to enhance construction work and services by using glass waste and explores ways to increase durability for improved construction performance and to meet recycling goals

The mechanical properties of interactive marine-terrestrial (IMT) deposit soils differ from those of other deposits as a result of the complex sedimentary environments in which they are found. The creep behaviors of IMT deposits in Ningbo, China were studied via triaxial drained creep testing. The theory of fractal derivatives was then applied to develop a fractal merchant model, in which a fractal

This article presents the results of a set of 28 large-scale triaxial tests, including 12 consolidated-drained (CD) static tests and 16 consolidated-undrained (CU) dynamic tests, on an artificially cemented gravel. The strength, dilatancy, stiffness and damping behaviour of both the cemented and the uncemented specimens are compared. Cementation is found to have interrelated effects on increasing the

Many foundations, such as those of industrial equipment, offshore structures and wind turbines, have to operate under repeated loads. Shakedown analysis is a powerful method that yields a straightforward calculation of a load limit below which the foundation will be stable under repeated loading. In this article, using the upper bound shakedown theorem by means of displacement finite element method

Junked tires encased slags pile composite foundation (JTES pile composite foundation for short) is a new method for treating soft soil ground. To study the vertical load-settlement characteristics and load-transfer mechanism of JTES pile composite foundation, vertical static load comparison tests in different loading conditions were investigated herein. The test results show that, the load-settlement

One of the most important material used in the construction industry is concrete. Adaptability with steel also provides the necessary tensile strength for constructing towering structures. However, concrete is susceptible to shrinkage during the curing process which produces micro cracks. These tiny fissures provide gateways to fluids for entering into concrete. The fluids undergo various reactions

This study investigates the carbonation behaviour of alkali-activated fly ash-based (AFA) concretes. AFA contains 20.67% of unburned carbon. GBFS and OPC were used as sources of calcium (20%). A mixture of NaOH and Na2SiO3 was used as activator. OPC concrete was used as reference material. AFA/GBFS, AFA/OPC and OPC concretes, with and without reinforcing steel, were exposed to accelerated carbonation

Ancient Chinese heritage buildings have high historical and artistic value. The bracket set in heritage buildings plays an important role in transferring and bearing load. However, over time, damage appears in these heritage buildings, which is especially serious in bracket sets. As damage seriously affects the safety and stability of the structure, studying the mechanical properties of the damaged

This paper focuses on the estimation of the maximum impact force of dry granular flow upon a rock shed using a coupled discrete element method (DEM) and finite element method (FEM). The dry granular flow is modeled as an assembly of discrete particles, and the rock shed is modeled by applying the FEM. The coupled DEM–FEM approach calibrated with a small-scale physical experiment is used to simulate

Continuous field monitoring during drifts excavation at the Meuse/Haute-Marne Underground Research Laboratory showed anisotropic hydromechanical responses, which are mainly evidenced in: (1) pore pressure field around the drifts with zones of marked overpressure; (2) the development of a dissymmetrical fractured zone induced by the excavation. These observations suggest that in addition to the initial

The proposed research of this experimental investigation aims to study the effects of fines content, fabrics type and confining pressure on the undrained shear strength response of Chlef sand-silt mixtures under static loading conditions using the equivalent void ratio (e*) and equivalent state parameter (ψ*) concepts. For this purpose, a series of undrained monotonic triaxial tests was carried out

This paper discusses a micromechanical parameter that governs the behaviour of textile-reinforced cementitious matrix composites (TRCMCs) under tensile load: load-transfer length. This parameter determines the number, location, and spacing of cracks in TRCMCs, and it depends on the interaction between the textile and the matrix. The objective of this study was to experimentally measure the load-transfer

Practical observations demonstrate that the corrosion deterioration of numerous reinforced concrete structures is due to the combination of carbonation and chloride ingress. However, the comprehensive combined model developed directly based on the coupling mechanism of them is very complicated. This article presents a simplified model to describe the transport of chloride ions with carbonation by introducing

Tunnel faces excavated under particularly difficult ground conditions are commonly supported. In case of conventional tunnelling, this support is provided by either improving the mechanical properties of the soil or introducing linear inclusions. This latter technique, consisting in the introduction of fibreglass pipes in the face, is particularly popular since it is very simple to tailor to the different

A series of triaxial unloading tests on integrated rock, triaxial compression tests and creep tests on unloading-cracked rock were carried out on dry and saturated specimens. The spatial and temporal distribution of microcracking process were obtained with the help of 3D acoustic emission (AE) monitoring system. The experiment data revealed that the saturation had a degeneracy effect on the transient

Alfa plant (Stipatenacissima L.) and wheat straw fibers were investigated as reinforcement in cementitious matrix. The fibers were used separately in three states: raw, wet (by immersion in water) and alkali treated. A reference mortar without fibers and mortars with 1% and 1.5% by volume of the two different bio-fibers were used. The mechanical and physical properties of mortar specimens were studied

This paper studies the effect of thermal cyclic loading on the mechanical properties of concrete such as cylinder and cube compressive strength, splitting and flexural tensile strengths, and weight loss. The specimens were exposed to 7–28 thermal cycles with peak temperatures of 100, 200 and 300 °C. A total of 120 specimens consisting of cubes, cylinders and prisms were tested in this study. The compressive

Maintaining the strength stabilisation is a precondition for reusing oil contaminated soil (OCS) in engineering projects. This study investigated the effects of coastal environment, such as temperature, humidity and water, on the strength and deformation of lime-fly ash solidified OCS. Results indicated that (i) The unconfined compressive strength (UCS), shear strength and deformation of OCS improve

To study the strength increasing rule of LWSCC in the process of freezing construction, some specimens were placed in cryogenic boxes at different subzero temperatures for curing, and the others were used as a control group for standard curing. After standard curing for 28 days, the specimens were placed in cryogenic boxes at different subzero temperatures for 1 day, and then the specimens were subjected

This article presents an analytical solution to predict the deformation of geosynthetic-encased stone columns (GESCs) and the surrounding soil in GESC-supported embankments, taking into account the effect of anisotropy of surrounding soil. Based on the theory of cylindrical cavity expansion, the elastoplastic constitutive relationship of the surrounding soil is described by the K0-based Modified Cam-Clay

Damage effect on surrounding rock is unavoidable during blasting excavation of deep underground caverns. In order to accurately analyse the damage degree of surrounding rock caused by explosive load under high ground stress conditions, an improved damage constitutive model of rock mass is proposed based on dynamic finite element numerical simulation software, and the continuous change processes of

(2020). Correction. European Journal of Environmental and Civil Engineering. Ahead of Print.

Multizone hydraulic fracture (HF) helps to enhance the commercial production rate of oil and gas in unconventional reservoirs. However, the efficiency of multizone HF highly depends on the cluster/perforation spacing and in situ stress field. Therefore, this paper investigates the phase field characteristic during multizone HF under different perforation spacing and in situ stress field. The total

Spatial variability of properties of geo-materials has a significant impact on the stability of landslides. In this paper, the spatial variability of soil properties of a landslide is modelled using random-field generated by the discrete cosine transform. The method developed can be readily applied to determine the probability of failure of the landslide using Monte Carlo simulation. A case study of

This paper focuses on effective elastic properties, and thermal conductivity of materials constituted by an isotropic homogeneous solid matrix containing both ellipsoidal and non-ellipsoidal pores. In the frame of Effective Media Theory (EMT), property contribution tensor approach extended to non-ellipsoidal inhomogeneities are used to estimate effective elastic properties and thermal conductivity

For high cutting slopes, it is quite necessary to set pre-reinforced structures before the slope excavation to avoid the slope failure during the excavating. In this paper, the multi-wedge translation mechanism is used to analyze the stability of high cutting slopes pre-reinforced with piles. First, the multivariate functions are established to calculate safety factor for the slope during the excavating

In this work, the stability of a shield tunnel face under pore water pressures is examined by combining the non-linear Mohr-Coulomb failure criterion in the framework of the kinematic approach of limit analysis. The non-linear Mohr-Coulomb failure criterion represented by the tangent technique in combination of the pore water pressure distribution calculated by the mesh dividing optimization technology

In recent years, a new type of composite column consisting of an impervious and stiffer core surrounded by a granular and pervious shell is emerging to improve soft soil in practice. This paper developed an analytical model for consolidation of soft ground improved by this type of composite column. Analytical solution is firstly derived for the soft soil stabilized by composite columns with circular

There is an ever-increasing awareness on issues connected with emission of high amounts of greenhouse gases from various industries, including that from the concrete construction industry. Performances of alternative binder systems including geopolymers and alkali activated slag concretes are being investigated in this context. There is again a continuous drive to enhance their performances, both when

Displacement prediction is a direct and effective method for mitigating geohazards. Due to the influence of rainfall and reservoir water level variations, landslides often display step-like deformations with an increasing trend and periodic fluctuation, indicating long-term memory in displacement time series. Traditional data-driven methods are mostly suitable for short-term prediction, and extra data

The strength, durability and swelling behavior of cement-solidified dredged sludge (CDS) has been attracted more and more attention in recent years. This study performed a series of laboratory tests including unconfined compressive strength (UCS), water absorption, swelling tests and pH to investigate the effectiveness of using fly ash (FA) and nano-SiO2 (NS) blended with Portland cement (PC) for DS

Experimental investigations were performed to evaluate the effect of waste Polyethylene Terephthalate (PET) fibres on the mechanical properties of Green Ultra-High Performance Cementitious Composites (GUHPCCs). Ultra-fine Palm Oil Fuel Ash (UPOFA) and Silica Fume (SF) were utilised to produce GUHPCCs that consist of up to 50% UPOFA and 20% SF as a partial replacement binder with cement. PET fibres

Cyclic action of wetting–drying (WD) is a main cause for the deterioration and failure of expansive soil canals. This paper presents details of an investigation dealing with the influences of WD cycles on the deterioration characteristics and failure modes of the canals in Xinjiang, China by laboratory and centrifugal model tests. The results show that the strength parameters of expansive soil have

The monitoring during one year of a gallery front of the Tournemire experimental station by optical metrology showed the presence of desiccation cracks sensitive to relative humidity variations in the gallery. The cracks are closed in summer, when RH is included between 90% and 98%, and open in winter when RH is lower. These cracks exhibit maximal aperture values ranging from 0.2 to 0.5 mm and different

Researchers put significant effort to decrease the environmental impact of concrete by using industrial by-products as an alternative binder. However, the considerable environmental impact still exists due to the consumption of natural resources as aggregates. Natural aggregates are the most used resources by volume in the construction sector. Therefore, it is necessary to investigate by-products as

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