Kaolin-nucleation-based biotreated calcareous sand through unsaturated percolation method

February 7, 2022, 12:00 am

≫ Next: Crushing strength of artificial single-particle considering the effect of particle morphology

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Ocean development is an effective and practical way to address resource issues, such as food, fuel, and land shortage. The current work proposed using kaolin-based biocement to stabilize calcareous sand which is always the main component of the foundations of ocean engineering. Five kinds of kaolin concentrations (0 g/L, 10 g/L, 20 g/L, 50 g/L, and 100 g/L) were selected to stabilize calcareous sand via the unsaturated percolation method. Besides, the saturated strength was determined to mimic the practical situations. The results showed that treatment cycles and raw materials can be reduced to obtain a given saturated strength when moderate kaolin is added. That is, the cost-performance of the MICP is improved. Besides, the maximum attainable saturated strength can be enlarged when a small dosage of kaolin is added. The distribution of precipitate contents along with the height of the specimens was also determined by the buoyancy method. Furthermore, a critical permeability range, i.e., \({1}{\text{.11}} \sim {2}{\text{.70}} \times {10}^{{ - 4}}\) m/s, is also distinguished from the permeability tests. The percolation method is not suitable for sand with a permeability smaller than this range.

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Crushing strength of artificial single-particle considering the effect of particle morphology

March 14, 2022, 12:00 am

≫ Next: A lateral soil resistance model for XCC pile in soft clay considering the effect of the geometry of cross section

≪ Previous: Kaolin-nucleation-based biotreated calcareous sand through unsaturated percolation method

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Particle geometry is a result of natural processes, such as the genesis of parent rock, particle transportation and depositional history. For granular materials, the particle morphology has a significant effect on its crushing strength in geotechnical engineering. The particle morphological parameters, sphericity, aspect ratio and convexity can be quantified with the aid of image processing techniques. In this study, a series of single-particle crushing tests were carried out to investigate the crushing strength and Weibull distribution of artificial single-particle while taking into account the effects of three representative particle morphologies: spherical, cubic and natural-morphology. On the basis of the test results, the crushing modes of the three particle morphologies were determined according to the force–displacement curves. The correlation between the survival probability and the given characteristic stress was discussed as well as the correlation between the 37% characteristic stress and the particle morphological parameters. In addition, the crushing strength distributions of the artificial particles with the three particle morphologies were described by Weibull distribution, and the Weibull moduli were also calculated. The applicability of Weibull distribution for granular materials with different morphologies was backed up further by a comparison of the predicted and observed average crushing stress. Then, the effect of particle morphology on the Weibull modulus was also presented. Furthermore, it can also be concluded that the fractal dimensions of different particle morphologies of the same materials differed under the same test conditions in the current study.

A lateral soil resistance model for XCC pile in soft clay considering the effect of the geometry of cross section

March 17, 2022, 12:00 am

≫ Next: In situ biomass flocculation improves placement of Sporosarcina Pasteurii for microbially mediated sandy soil stabilization

≪ Previous: Crushing strength of artificial single-particle considering the effect of particle morphology

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In this paper, a series of well-calibrated finite-element analyses are performed to quantify the influence of the geometry of cross section on the load transfer mechanism of X-section Cast-in-place Concrete (XCC) pile under lateral load, aiming to propose a lateral soil resistance model for XCC pile in soft clay. Based on the results of the numerical parametric analysis, the failure mechanism of soil flow and the ultimate lateral soil pressure are investigated to reveal the underlying mechanism that controls the cross-section geometry-dependency response. Finally, a general p-y formula for XCC pile, which can well capture the lateral behavior of XCC pile considering the various cross section geometries, is developed. In addition, compared with the traditional circular cross section pile with the same area, the XCC pile is more effective in terms of resistance to lateral load.

In situ biomass flocculation improves placement of Sporosarcina Pasteurii for microbially mediated sandy soil stabilization

March 17, 2022, 12:00 am

≫ Next: A simple estimation model for basal heave stability of braced excavations in anisotropic clay

≪ Previous: A lateral soil resistance model for XCC pile in soft clay considering the effect of the geometry of cross section

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Microbially induced carbonate precipitates (MICPs) through ureolysis-driven calcite precipitation have been investigated as a mean of improving the mechanical properties of soil (cohesion, friction, stiffness, and permeability). To achieve a well-controlled and uniform MICP, it is crucial to obtain a homogeneous distribution of bacterial activity. This paper describes a new and simple method to maximize the retention of bacteria in porous silica sand, where the retained bacteria with their activity are distributed homogeneously. This method is based on a novel in situ biomass flocculation technique induced by the presence of a trace amount of Ca²⁺ and increased alkalinity of the environment due to the hydrolysis of urea. The method has been tested in both 300 mm and 1000 mm sand columns, in which the retained urease activity, content of the produced CaCO₃, and final unconfined compressive strength were homogeneously distributed throughout the entire treated columns. The presented bacterial fixation method could also be potentially used to deliver and fix specific bacteria in a target zone. Overall, this method of improving bacterial fixation in porous media can be used for bio-cementation ground improvement, ensuring the uniform performance of treated soils.

A simple estimation model for basal heave stability of braced excavations in anisotropic clay

March 23, 2022, 12:00 am

≫ Next: A simplified analysis approach for the effect of the installation of adjacent XCC pile on the existing single XCC pile in undrained clay

≪ Previous: In situ biomass flocculation improves placement of Sporosarcina Pasteurii for microbially mediated sandy soil stabilization

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Abstract

The basal heave stability of the excavation and support system is a major concern to geotechnical design engineers, particularly in soft clay deposits. Conventional methods for estimating the basal heave stability of braced excavations generally do not consider the anisotropy of the soft clay, which may lead to the incorrect assessment of excavation stability. This study presents the results of extensive finite element analysis to investigate the influence of clay anisotropy on basal heave stability. The parameters that were considered include the ratio of the plane strain passive shear strength to the plane strain active shear strength \(s_{{\text{u}}}^{{\text{P}}} /s_{{\text{u}}}^{{\text{A}}}\), the ratio of the unloading/reloading shear modulus to the plane strain active shear strength \( G_{{{\text{ur}}}} /s_{{\text{u}}}^{{\text{A}}}\), the plane strain active shear strength \(s_{{\text{u}}}^{{\text{A}}}\), soil unit weight γ, wall system stiffness ln(S), excavation width B, excavation depth H_e, and the wall penetration depth D. A simple logarithmic regression model was developed for preliminary assessment of the basal heave factor of safety for braced excavations in anisotropic clay. Validations from case histories indicate that the proposed model can provide reasonable predictions of the basal heave stability in soft clay.

A simplified analysis approach for the effect of the installation of adjacent XCC pile on the existing single XCC pile in undrained clay

March 26, 2022, 12:00 am

≫ Next: Enhancing splitting tensile strength of biocarbonated reactive magnesia-based sand using polypropylene fiber reinforcement

≪ Previous: A simple estimation model for basal heave stability of braced excavations in anisotropic clay

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In this paper, a simplified two-stage analysis method is introduced to predict the lateral response of the existing X-section Cast-in-place Concrete (XCC) pile caused by adjacent XCC pile installation. Firstly, the large deformation finite element method, namely the Coupled Eulerian–Lagrangian (CEL) numerical technique, is employed to simulate the installation process of XCC pile, thus accurately capturing the lateral soil movement in free field induced by adjacent XCC pile penetration. Secondly, the free-field lateral soil displacement load is imposed on the existing XCC pile, and then the lateral behavior of the existing XCC pile is solved by employing the theory of nonlinear foundation beam. Then, the validation of the presented simplified analysis method is proved by comparison with the numerical results of the adjacent XCC pile–soil–existing XCC pile CEL model (PSP CEL model), and good consistencies are acquired. Finally, the parametric studies are performed to evaluate the impact of various parameters on the lateral behavior of the existing XCC pile. The proposed analysis method can be applied to the early phase of engineering design to alleviate the hazards related to the adjacent XCC pile–soil–existing XCC pile interaction.

Enhancing splitting tensile strength of biocarbonated reactive magnesia-based sand using polypropylene fiber reinforcement

April 16, 2022, 12:00 am

≫ Next: Improvement of uniformity of biocemented sand column using CH3COOH-buffered one-phase-low-pH injection method

≪ Previous: A simplified analysis approach for the effect of the installation of adjacent XCC pile on the existing single XCC pile in undrained clay

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This short communication investigates the involvement of polypropylene fibers in the biocarbonated reactive magnesia cement mixes to improve the splitting tensile strength of sand for soil improvement. By varying the RMC content (5 and 10% by weight of sand) and fiber content (0, 0.5, and 1% by weight of sand), a suitable mix design was determined. The test results showed that the peak tensile strength of biocarbonated RMC-based sand samples with an optimum fiber content of 1% could improve by more than 4 times compared to the biocarbonated sand without fiber reinforcement. This was attributed to the generation of hydrated magnesium carbonates with the microbially induced CO₂/carbonate process, bonding the fiber–matrix and eliminating the brittleness, consequently enhancing the tensile ductility of biocarbonated sand.

Improvement of uniformity of biocemented sand column using CH3COOH-buffered one-phase-low-pH injection method

May 9, 2022, 12:00 am

≫ Next: Mechanical properties of biocement formed by microbially induced carbonate precipitation

≪ Previous: Enhancing splitting tensile strength of biocarbonated reactive magnesia-based sand using polypropylene fiber reinforcement

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Biocement based on a Microbially Induced Calcite Precipitation (MICP) process has emerged to be a promising alternative to cement for soil improvement. A two-phase injection method is commonly used for the MICP treatment of granular soil. However, the samples treated using this method may not be uniform. Recently, an acidified one-phase-low-pH injection method was developed using HCl as a buffer. This method could improve the uniformity of the MICP treatment to a certain extent. However, the distance in which the soil could be treated uniformly is still limited. This paper presents a CH3COOH-buffered one-phase-low-pH method which could improve the uniformity of biocement treatment considerably compared with the one-phase-low-pH method based on HCl. The key feature of this method is to create a much longer lag duration; thus, the biocementation process can be delayed and allow the all-in-one solution to be distributed more uniformly in soil within the lag duration. The uniformity of MICP-treated 1-m and 2-m sand columns was evaluated by comparing the unconfined compressive strengths and the calcium carbonate contents measured at different locations along the sand columns. The test results show that the proposed method is much more effective in improving the uniformity of the MICP treatment though a significant increase in the lag duration, given the other conditions the same.

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Mechanical properties of biocement formed by microbially induced carbonate precipitation

May 26, 2022, 12:00 am

≫ Next: 3D Discrete Element Modeling of Sands Treated by Microbially Induced Calcium Carbonate Precipitation

≪ Previous: Improvement of uniformity of biocemented sand column using CH3COOH-buffered one-phase-low-pH injection method

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The failure of biocemented sand can be attributed to the breakage of biocement and the exfoliation of precipitates from sand surfaces. Therefore, optimizing the mechanical properties of the biocement is one of the methods to improve the performance of MICP for stabilizing sand. Besides, a deep understanding of the properties of biocement is necessary for simulating and establishing constitutive models to predict the mechanical properties of biocemented sand. In this paper, Brazil splitting tensile strength tests were conducted on the biocement formed under different concentrations of cementation solutions, volume ratios of bacterial solutions to cementation solutions, temperature, and bacterial suspension types. The above factors cannot only affect the distribution of precipitates both at the microscale and macroscale, which were always regarded as the main reason for the different strength of biocemented sand earlier, but also affect the physical–mechanical properties of biocement, which was the contribution of the current work.

3D Discrete Element Modeling of Sands Treated by Microbially Induced Calcium Carbonate Precipitation

January 1, 2023, 12:00 am

≫ Next: Microscopic investigation on bonding fracture of biocemented sand from novel in situ brazil splitting tests

≪ Previous: Mechanical properties of biocement formed by microbially induced carbonate precipitation

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Microbially induced calcium carbonate precipitation (MICP) has the capability to improve engineering properties of sands and has attracted plenty of attentions recently. 3D discrete element modeling is conducted herein to investigate the MICP process from the perspective of micromechanics. The sand particles are represented by large particles and the calcium carbonate (CaCO₃) formed during the MICP process are modeled with fine particles. The sand skeleton is formed first with coarse particles only, and random fine particles are generated within the pore space of the skeleton thereafter. The fines precipitate to the interparticle contacts or particle surfaces under random external driving forces, which is designed to mimic the MICP process in reality. Different roles of fines, including pore-filling, coating and bonding, are formed naturally during the virtual precipitation process given the randomness. The good agreement between the numerical results and the experimental data validates the proposed model and proves its capability and potential for modeling the mechanical responses of MICP-treated sands and analyzing the underlying mechanisms.

Microscopic investigation on bonding fracture of biocemented sand from novel in situ brazil splitting tests

September 2, 2022, 12:00 am

≫ Next: An analytical solution of electroosmotic consolidation concerning effective voltage attenuation

≪ Previous: 3D Discrete Element Modeling of Sands Treated by Microbially Induced Calcium Carbonate Precipitation

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The failure mechanism of biocemented sand has been largely speculated based on scanning electron microscopy images of biocemented sand after mechanical tests. However, some breakage patterns cannot be directly observed, such as the separation of CaCO₃ crystals and the separation of CaCO₃ crystals and sand surfaces. A study of the breakage process of biocemented sand at microscale is essential for understanding the mechanism of biocementation. In this work for the first time, a series of in situ splitting tensile tests were conducted using a tensile & compression module installed inside an SEM machine so that the breakage process of a biocemented sample under loading could be observed directly. The results showed that no breakage was observed before peak stress indicating an elastic–plastic deformation stage. Once the peak stress was reached, the stress fluctuated around the peak stress. At the end of the tests, two kinds of breakage of biocement were observed, i.e., calcite-calcite breakage and calcite-silica breakage. The detailed breakage seems also affected by the form of CaCO₃. Furthermore, besides increasing active precipitates, the improvements in the strength of biocement and the bonding strength between biocement and the sand surface were suggested to improve the performance of MICP for stabilizing sand. The findings of microscale in situ observation during mechanical tests can also provide basic evidence for modeling debonding process of biotreated soils using constitutive models or numerical simulation methods.

An analytical solution of electroosmotic consolidation concerning effective voltage attenuation

September 9, 2022, 12:00 am

≫ Next: A constitutive model incorporating particle breakage for gravelly soil-structure interface under cyclic loading

≪ Previous: Microscopic investigation on bonding fracture of biocemented sand from novel in situ brazil splitting tests

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The effective voltage of soil refers to the actual voltage which is acting on the soil. When electroosmosis is adopted to strengthen the soft foundation, the soil effective voltage is less than the applied power supply voltage. The effective voltage of the soil gradually decreases with the progress of electroosmosis and tends to reach a stable value. In this regard, based on the analysis of the experimental results that the soil effective voltage first undergoes a linear decrease over time and then remains unchanged, the classical electroosmotic consolidation theory proposed by Esrig is modified in this paper in order to obtain a new analytical solution of excess pore water pressure. Then, the analytical solution is verified by a specific experimental case and compared with Esrig’s theory. The results indicate that the theoretical value of excess pore water pressure, which was obtained from the modified electroosmotic consolidation equation, is closer to the measured value and caters better to the actual situation in comparison with Esrig’s theory. This provides evidence for the rationality of the analytical solution and further improves the existing electroosmotic consolidation theory.

A constitutive model incorporating particle breakage for gravelly soil-structure interface under cyclic loading

September 13, 2022, 12:00 am

≫ Next: Comparative numerical analysis of the response of laterally loaded pile in coral and silica sands

≪ Previous: An analytical solution of electroosmotic consolidation concerning effective voltage attenuation

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Under cyclic loading, particle breakage occurs at gravelly soil-structure interface, resulting in the decrease of interface strength and the increase of normal displacement. Based on the theory of critical state soil mechanics, the modified Cam-Clay model (MCC) was extended to the plane strain condition of the interface, the state parameter was introduced and the influence of particle breakage on the critical state line was considered, and the cyclic constitutive model for gravelly soil-structure interface considering particle breakage was established by using the non-associated flow rule. Then, the established cyclic constitutive model was used to simulate large-scale cycle direct shear tests of Zipingpu rockfill-steel interface and Zipingpu rockfill-concrete interface under constant normal load (CNL) and constant normal stiffness (CNS), respectively. The simulation results show that under the CNL cyclic loading path, there is little difference between the cyclic shear stress considering particle breakage and that without particle breakage, but the normal displacement considering particle breakage is larger than that without particle breakage, and the difference increases with the increasing number of cycles and normal stress; Under the CNS cyclic loading path, with the increase of the number of cycles, the cyclic shear stress and cyclic normal stress considering particle breakage is significantly smaller than that without particle breakage, and the shear contraction of normal displacement becomes more obvious. In general, the simulation results are closer to the experimental results when particle breakage is considered.

Comparative numerical analysis of the response of laterally loaded pile in coral and silica sands

March 28, 2023, 12:00 am

≫ Next: Small strain stiffness of graded sands with light biocementation

≪ Previous: A constitutive model incorporating particle breakage for gravelly soil-structure interface under cyclic loading

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This paper presents the lateral pile-soil response occurring in coral and silica sand foundations through comparative numerical studies. In this study, the Hypoplastic constitutive model was implemented into Abaqus software to simulate the stress–strain relationship of coral sand and silica sand with the same particle gradation. The validation of numerical model was verified by centrifuge test results. Afterward, forty-eight numerical analyses were employed to assess the influence of pile diameter, embedment length, loading eccentricity, and relative density on the lateral response of piles in two kinds of sands. The load–displacement response, pile deflection, bending moment, and p-y curves were compared and analyzed in detail. The results showed that, with the increase in displacement level and relative density, the load responses of piles in coral sand gradually became greater than that in silica sand, the p-y curves in coral sand were also significantly higher than that in silica sand, and the bending moment and deflection profile of pile in silica sand were larger than that in coral sand. The difference in pile response between the two kinds of sands became more significant as the density and load level increased. Finally, a multi-parameter modified p-y model for coral sand was proposed, and its applicability and rationality were validated.

Small strain stiffness of graded sands with light biocementation

April 14, 2023, 12:00 am

≫ Next: Microfluidic experiments of biological CaCO3 precipitation in transverse mixing reactive environments

≪ Previous: Comparative numerical analysis of the response of laterally loaded pile in coral and silica sands

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Particle size gradation is an important parameter for small strain stiffness of sand, and it can also affect the biocementation behavior. In this study, a series of isotropic consolidation tests were performed to study the gradation-dependent small strain shear modulus of a glass sand with light biocementation. Shear wave velocities in multi-directions were measured with bender elements. The test results showed that the small strain shear modulus G₀ and stiffness anisotropy decrease and increase with the increase in uniformity coefficient Cu, respectively, for the uncemented sand. When sands were biocemented, the decrement of G₀ gradually vanishes with biocementation level, showing that G₀ increases with Cu. The development of G₀ ratios between the biocemented and the uncemented sands generally experiences four stages. The stiffness anisotropy is also changed with biocementation, showing the decrease in stiffness ratio especially for the unloading stages. The changes of stiffness anisotropy are more explicit for the sands with higher Cu and biocementation level.

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Microfluidic experiments of biological CaCO3 precipitation in transverse mixing reactive environments

June 12, 2023, 12:00 am

≫ Next: Experimental study on the development of surrounding soil stress during XCC pile installation in sand

≪ Previous: Small strain stiffness of graded sands with light biocementation

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Enzymatically induced carbonate precipitation (EICP) in heterogeneous subsurface is of interest in various geoscience and environmental applications. Through fabricating microfluidic cells with different pore networks, the pore-scale formation of biological CaCO₃ was investigated experimentally by transverse mixing using time lapse high-resolution camera. The precipitation pattern over time was processed to obtain the evolution of distribution of CaCO₃ volume fraction. The impact of flow rate and pore-scale heterogeneity were quantitatively evaluated with reaction index including overall pore filling ratio, precipitation rate and precipitation efficiency. The results showed that low flow rates and strong heterogeneity in porous media are the two favorable conditions for precipitation process due to more nucleation sites. At grain scale, a statistic of three-dimensional morphologies of individual crystals was evaluated with specific surface area and degree of anisotropy. Localized precipitates in multiple pores were adopted as a representative of the whole porous media. The analysis showed that the complex pore structures are generated due to precipitates in pores, thus limiting transport of reactants and result in the permeability reduction. We furthermore confirmed different polymorphs of calcium carbonate, mainly containing vaterite and calcite. Pore-scale analysis of biological CaCO₃ in porous media significantly contributes to the understanding of advection–diffusion-reaction coupling effect, and further revealing the role of pore network on biomineralization process.

Experimental study on the development of surrounding soil stress during XCC pile installation in sand

December 6, 2023, 12:00 am

≫ Next: Analytical solution of the shallowest overburden thickness of special-shaped shield tunnel in layered soil

≪ Previous: Microfluidic experiments of biological CaCO3 precipitation in transverse mixing reactive environments

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A series of small-scale 1 g model tests were conducted using a self-designed pile driving loading model test system to investigate the effect of relative density and cross-section geometry on the development of soil stress around the pile during the penetration of X-section Cast-in-place Concrete (XCC) pile in sand. It is found that the variations of the radial stress Δσ'_r/σ'_v0 in the surrounding soil presented a significant “h/R effect” during the penetration of the XCC pile, indicating that the “h/R effect”, which was found for circular pile during the penetration of piles, was also observed for the XCC pile. The radial stress distribution along the axial direction of the pile could be divided into three zones, i.e., the pile body region, the pile tip region, and the soil region below the pile tip. The development trend of the radial stress along with soil depth is different in each region. Additionally, the peaks of the radial stresses in the pile tip region were very sensitive to the variations of the relative density of the surrounding soils and the cross-section geometry of the piles, which increased significantly with increasing the relative density and cross-section geometry. The radial stresses Δσ'_r/σ'_v0 decreased exponentially as the radial distance r/R increased. The decay rates decreased with increasing the relative densities of the surrounding soils, while increased with decreasing the cross-section geometry parameter of the piles.

Analytical solution of the shallowest overburden thickness of special-shaped shield tunnel in layered soil

December 11, 2023, 12:00 am

≫ Next: Centrifuge model tests on bearing behavior of lateral-loaded single pile in coral sand

≪ Previous: Experimental study on the development of surrounding soil stress during XCC pile installation in sand

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The water-rich shield tunnel plays a significant role in the rapid development of underground space construction. The use of various special-shaped shield tunnels is gradually emerging for the need of functional diversity. In this study, a shield tunnel shape coefficient was proposed, and the analytical solution for the shallowest overburden thickness of special-shaped shield tunnels in double-layered soil was derived using both linear and nonlinear soil resistance models. The variables influencing the shallowest overburden thickness of shield tunnels were analyzed, and the buoyancy of shield tunnels at different construction stages was discussed. Furthermore, the solution to determine the shallowest overburden thickness of shield tunnels in multi-layered soil was presented. It was observed that the shallowest overburden thickness of shield tunnels is negatively correlated with the tunnel shape coefficient, the longest length of the cross section, and the cohesion, internal friction angle, and submerged bulk density of the soil layer. The analytical solution for the shallowest overburden thickness, considering the shear force based on the nonlinear soil resistance model, is more conducive to ensuring the anti-floating stability of the shield tunnel without excessive anti-floating capacity.

Centrifuge model tests on bearing behavior of lateral-loaded single pile in coral sand

December 22, 2023, 12:00 am

≫ Next: Full-field internal 3D deformations measurement of transparent soil using 3D-DIC combined with optical slicing

≪ Previous: Analytical solution of the shallowest overburden thickness of special-shaped shield tunnel in layered soil

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In this study, centrifuge model tests were carried out to investigate the lateral response of single pile in coral sand foundation. The load–displacement relationships, pile deflections, bending moments, the changes in horizontal soil pressure, the predicted particle crushing behaviors, and p-y curves were compared and discussed in detail to study the influence of pile diameter and vertical load. Test results show that increasing diameter is the most direct and effective method to improve the horizontal bearing capacity of pile; the presence of vertical load would lead to an increase of bending moment and lateral displacement of the pile due to P-Δ effect and an improvement in soil resistance due to the vertical compression effect; the influence of particle breakage behavior of coral sand was not significant. In addition, the applicability of the existing p-y models for the coral sand foundation was systematically evaluated. According to the comprehensive analysis of the stress state of sand around pile, the evolution of soil resistance with depth was determined, which can be simulated by a power function. Based on the centrifuge test results, a modified p-y model for coral sand was proposed, and its rationality and applicability in predicting pile–soil responses were validated systematically.

Full-field internal 3D deformations measurement of transparent soil using 3D-DIC combined with optical slicing

February 23, 2024, 12:00 am

≪ Previous: Centrifuge model tests on bearing behavior of lateral-loaded single pile in coral sand

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Digital image correlation (DIC) and particle image velocity (PIV) are highly effective non-contact methods to accurately measure full-field deformations in transparent soil model testing (TSMT). The nature of transparent soils combined with the rapid development of three-dimensional (3D) DIC/PIV techniques means that the acquisition of the full internal 3D deformations is now technically feasible. However, current approaches focus on two-dimensional (2D) in-plane displacements and typically ignore out-of-plane displacements. This paper presents an approach of combining 3D-DIC with optical slicing to observe 3D movements of transparent soil using custom MATLAB programming. A rigid body motion (RBM) test of a transparent soil sample is first conducted to estimate the accuracy of the proposed algorithm. A vertically loaded circular footing test is subsequently performed as a proof of concept; multiple-slice images of the soil are captured using a new experimental apparatus and processed by the 3D-DIC algorithm, and the resultant 3D displacements of all slices are reconstructed to visualize the soil deformations in 3D space. The findings confirm that the proposed 3D-DIC algorithm is accurate and the optical slicing with supplementary spatial reconstruction method enables visualization of transparent soil in 3D space, which can be used in future TSMT.