The effect of particle shape on the strength, dilatancy, and stress-dilatancy relationship was systematically investigated through a series drained triaxial compression tests sands mixed with angular rounded glass beads different proportions (0%, 25%, 50%, 75%, 100%). A distinct overall regularity parameter used to define these mixtures, which ranged from 0.844 0.971. test results showed that all samples at an initial relative density 0.6 exhibited strain-softening volume-expansion behavior....

Particle breakage has a great influence on stress-strain behaviors of rockfill materials. A new relative was proposed for critical state line incorporating particle termed as (BCSL). It found that the BCSL position materials pertained to breakage. An elastoplastic model considering dependence and The effect incorporated into parameter, dilatancy stress ratio, relation, bounding plastic modulus in model. can well predict particle-breakage at various confining pressures.

The influences of particle breakage on the position critical state line (CSL) were systematically investigated in this paper through a series large-scale triaxial compression tests Tacheng rockfill material (TRM). It was found that critical-state stress ratio TRM (i.e., gradient CSL p−q space) approximately regarded as constant. In e−logp space, descended with decrease initial void ratio, whereas A procedure established for evaluating point at same breakage, which comprised (BCSL). An...

Calcareous sands are known as problematic soils in nature and challenge geotechnical engineers many practical projects. Microbially induced calcite precipitation (MICP) is an innovative soil improvement technique that uses biomineralisation processes to induce cementation in-situ. The work described this paper investigates the strength, deformation, microstructure characteristics of biocemented calcareous sand under different solution sample volume ratios. A series laboratory experiments was...

The strength properties of basalt fiber–reinforced biocemented (BFRB) sand specimens with various calcite contents and fiber are investigated through a series unconfined compressive splitting tensile tests. Reverse injection is introduced to improve the uniformity calcium carbonate precipitation. test results show that both (UCS) (STS) at given content increase significantly increasing content, whereas axial strain peak failure state decreases content. improved ductility has implications for...

Microbial-induced calcium carbonate precipitation (MICP) represents a promising approach to improve the geotechnical engineering properties of soils through (CaCO 3 ) at soil particle contacts and surfaces. An extensive experimental study was undertaken investigate influence initial relative density on efficiency biocementation process, reduction liquefaction susceptibility, cyclic response in biocemented calcareous soils. For this purpose, stress-controlled undrained triaxial shear (CTS)...

To effectively stabilize coarse sand, bentonite was introduced in microbially induced carbonate precipitation (MICP) grouting. Varying concentrations (0, 20, 40, and 80 g/L) of were added to bacterial suspensions (BSs), which magnetically stirred form bacterial-bentonite (BBSs). Then, sand specimens treated with BBSs cementation solutions (CSs) different levels. The results showed that the addition could increase volume fractions precipitates consisting calcium (CaCO 3 ) bentonite....

The particle breakage and compressibility behavior of sands treated with microbially induced carbonate precipitation (MICP) has been investigated using oedometric compression tests. acid washing technique was used to obtain the calcium (CaCO3) content facilitate quantification by measurement size distribution (PSD). It found that lower for specimens a large CaCO3 content. Particle increased an increase in stress or input work approximately same In addition, given applied work, MICP-treated...

A significant pressing issue in microbially induced calcium carbonate precipitation (MICP) is the characterization of heterogeneous growth mechanics (CaCO3) crystals. This study aimed to visualize bacteria and CaCO3 distributions at quiescent state through microfluidic chip tests where bacterial solution (BS) cementation (CS) were initially injected simultaneously from two separate microchannels subsequently converged a reaction microchannel. The experiments revealed that diffusion within CS...

Abstract Microbially induced calcium carbonate precipitation (MICP) has attracted much attention as a promising green technique for soil improvement. Despite the significance of pattern in mind, constitutive relations or numerical models considering finite‐strain mechanical effects various patterns are rarely developed. In this paper, we propose novel 3D DEM modeling scheme by using coarse particles to represent sand grains and fines cementing agents, reproduce MICP‐treated sand. Based on...

ABSTRACT In geo‐energy engineering projects, temperature is an essential environmental variable, and accurately predicting its effect on the thermomechanical properties of geomaterials remains a challenge. Similar to fine‐grained soils, variation also crucial factor that affects stress‐strain response critical state behavior coarse‐grained soils. this study, model established for soils using theories from fractional plasticity. The evolution line with increasing can be well characterized by...

Strength and deformation behaviors of rockfill materials, key factors for determining the stability dams, pertain strongly to grain crushing characteristics. In this study, single-particle tests were carried out on materials with nominal particle diameters 2.5 mm, 5 mm 10 investigate size effect strength relationship between characteristic stress probability non-failure. Test data found be described by Weibull distribution modulus 3.24. Assemblies uniform grains then subjected...

Microbially induced calcite precipitation (MICP) has attracted significant attention as a promising in situ ground reinforcement method, particularly for the improvement of existing structure foundations. Prior to its widespread application, further study is required answer questions that seek improve understanding fundamental mechanisms cementation. This paper focuses on influence particle shape stiffness and strength MICP-treated glass beads through series unconfined compression tests. The...

The true triaxial compression test is the three-dimensional test, where intermediate principal stress not less than minor and more major stress. effect of ratio (i.e., b-value) on particle breakage rockfill material (RFM) was investigated by conducting a series tests under constant-p′ constant-b loading condition. It observed that relative extent RFM increased with an increase in confining pressure but decreased b-value. b-value well predicted empirical equation.

A series of large-scale triaxial compression tests were conducted to investigate the strength and deformation behaviors Tacheng rockfill material (TRM) in relation initial void ratio confining pressure. The critical state friction angle TRM was expressed as a linear function logarithm excess peak characteristic formulated equations revised relative dilatancy index capture influences density pressure on angles. elastic modulus, tangent secant modulus dependent In addition, formulation...

The amount of particle breakage Tacheng rockfill material (TRM) in the process shearing was quantitatively measured by a relative index. fractal dimension TRM at final state tests found to be linearly related void ratio and logarithm confining pressure. influences index on friction angle, modulus, deformation were investigated based series large-scale triaxial compression TRM. An increase leads an volumetric strain decreases peak critical deviatoric strain, ratio. test results used propose...