Geomechanics and Engineering最新文献_第5页

Effect of microstructure on water retention behavior of lateritic clay over a wide suction range 大吸力范围内红土粘土微观结构对保水性能的影响

IF 3.2 3区工程技术

Geomechanics and Engineering Pub Date : 2021-01-01 DOI: 10.12989/GAE.2021.25.5.417

Jin Pan, Zhen Wenzhan, Bo Chen, De’an Sun, You Gao, Y. Xiong

{"title":"Effect of microstructure on water retention behavior of lateritic clay over a wide suction range","authors":"Jin Pan, Zhen Wenzhan, Bo Chen, De’an Sun, You Gao, Y. Xiong","doi":"10.12989/GAE.2021.25.5.417","DOIUrl":"https://doi.org/10.12989/GAE.2021.25.5.417","url":null,"abstract":"To investigate the effects of soil structrue and dry density on water retention behavior of lateritic clay over a wide suction range, the axial translation technique (ATT), filter paper technique (FPT) and vapour equilibrium technique (VET) were combined to obtain soil-water retention curves (SWRCs) of specimens with different structures and dry densities. Measured SWRCs indicate that the air-entry value (AEV) and descent gradient in terms of saturation degree versus suction relationship are smallest for undisturbed specimens, and are largest for pre-consolidated specimens. The SWRCs obtained from compacted specimens with different dry densities illustrate that the AEV and descent gradient of saturation degree versus suction relationship increase with increasing the dry density. However, the effects of soil structure and dry density on the water retention behavior can be negligible at high suctions, which are verified by the curves of gravimetric water content (w) verusus suction (s) coincided after a limiting suction for specimens with different structures and dry densities. In addition, the water retention behavior can be well illustrated by pore size distributions (PSDs), obtained from mercury intrusion porosimetry (MIP). The AEVs depend on the diameters that corresponding to dramatically increase in differential intruded void ratio. And the descent gradients in the saturation degree versus suction relationship depend on their distinct PSD ranges and incremental peaks in the dominant pore sizes. Furthermore, the consistences of the AEVs and limiting suctions, deduced from the PSDs and SWRCs, demonstrate that the water retention behavior is highly dependent on the PSDs, and the SWRC features can be captured well by the PSDs.","PeriodicalId":12602,"journal":{"name":"Geomechanics and Engineering","volume":null,"pages":null},"PeriodicalIF":3.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66477195","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Development of orthotropic Winkler-like model for rotating cylindrical shell: Stability analysis 旋转圆柱壳正交各向异性类温克勒模型的建立:稳定性分析

IF 3.2 3区工程技术

Geomechanics and Engineering Pub Date : 2021-01-01 DOI: 10.12989/GAE.2021.26.3.253

M. Khadimallah, M. Hussain, Yahya Ahmad, Elaloui Elimame, A. Tounsi

引用次数: 1

End bearing capacity of embedded pile with inclined base plate:Field dynamic and static tests 斜底板预埋桩端部承载力:现场动、静力试验

IF 3.2 3区工程技术

Geomechanics and Engineering Pub Date : 2021-01-01 DOI: 10.12989/GAE.2021.26.3.261

Mi-Jeong Seo, Kyungsoo Han, Jongbae Park, Kyeong-han Jeong, Jong Sub Lee

{"title":"End bearing capacity of embedded pile with inclined base plate:Field dynamic and static tests","authors":"Mi-Jeong Seo, Kyungsoo Han, Jongbae Park, Kyeong-han Jeong, Jong Sub Lee","doi":"10.12989/GAE.2021.26.3.261","DOIUrl":"https://doi.org/10.12989/GAE.2021.26.3.261","url":null,"abstract":"The objective of this study is to investigate the effects of incorporating inclined base plates on the end bearing capacities of embedded piles by conducting dynamic pile tests and static load tests. Two types of embedded piles were prepared – conventional piles with a 50-cm-diameter flat base plate and piles with a 56-cm-diameter inclined base plate. The dynamic pile tests were conducted during pile construction, and the static load tests were conducted after curing the cement paste to investigate the end bearing capacities of the test piles. Test results indicate that the base resistances of piles with inclined base plates are greater than those of conventional piles and that the base resistances increase with an increase in the inclination angle. The increased projected area, increased contact area, extended rupture surface, and enhanced slime discharge due to the inclined base plate may result in an increase in the end bearing capacity of the pile. This study demonstrates that the end bearing capacities of the embedded piles may be maximized by incorporating inclined plates to the pile base. Thus, the pile with the inclined base plate may be effectively used for the construction of embedded piles.","PeriodicalId":12602,"journal":{"name":"Geomechanics and Engineering","volume":null,"pages":null},"PeriodicalIF":3.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66478363","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Influence of a preset fissure on clay behavior under uniaxial compression 单轴压缩下预设裂隙对粘土特性的影响

IF 3.2 3区工程技术

Geomechanics and Engineering Pub Date : 2021-01-01 DOI: 10.12989/GAE.2021.26.4.357

W. Wang, Bin Zhao, Aiyu Hu, J. Shang

{"title":"Influence of a preset fissure on clay behavior under uniaxial compression","authors":"W. Wang, Bin Zhao, Aiyu Hu, J. Shang","doi":"10.12989/GAE.2021.26.4.357","DOIUrl":"https://doi.org/10.12989/GAE.2021.26.4.357","url":null,"abstract":"Under compression, the flaws in soils will not only weaken the mechanical properties of soils, but also affect the strain localization of soils. In order to study the influence of flaws on the behavior of soils under compression, the uniaxial compression tests of clays with different inclination and position fissures were carried out, and the two-dimensional numerical analysis was also discussed based on the damage plasticity model. Analyzing the results of the uniaxial compression test and simulation of the intact and fissured clays, the following conclusions can be drawn: (1) The 60-degree fissure located on the upper position of the right edge of the clay has the greatest influence on the failure form and damage energy of clays, which can reduce the compression strength by 30% compared with that of the intact clay. (2) The numerical method based on the damage plasticity model can basically simulate the compression behavior of clays containing a pre-existing fissure and reproduce the failure characteristics of clays. (3) The preset fissure has obvious influence on the evolution of maximum principal stress in the area with serious damage, but less on the shear stress. And in the area with slight damage, the effect on the maximum principal stress and shear stress is very weak.","PeriodicalId":12602,"journal":{"name":"Geomechanics and Engineering","volume":null,"pages":null},"PeriodicalIF":3.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66479288","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effects of soaking on a lime stabilized clay and implications for pavement design 浸水对石灰稳定粘土的影响及其对路面设计的启示

IF 3.2 3区工程技术

Geomechanics and Engineering Pub Date : 2021-01-01 DOI: 10.12989/GAE.2021.24.2.115

I. Bozbey, M. K. Kelesoglu, S. Oztoprak, Muhammet Komut, Senol Comez, T. Ozturk, Aykan Mert, K. Ocal

引用次数: 4

Reliability analysis of strip footing under rainfall using KL-FORM 基于KL-FORM的条形基础雨下可靠度分析

IF 3.2 3区工程技术

Geomechanics and Engineering Pub Date : 2021-01-01 DOI: 10.12989/GAE.2021.24.2.167

Suozhu Fei, Xiaohui Tan, W. Gong, Xiaole Dong, F. Zha, Long Xu

{"title":"Reliability analysis of strip footing under rainfall using KL-FORM","authors":"Suozhu Fei, Xiaohui Tan, W. Gong, Xiaole Dong, F. Zha, Long Xu","doi":"10.12989/GAE.2021.24.2.167","DOIUrl":"https://doi.org/10.12989/GAE.2021.24.2.167","url":null,"abstract":"Spatial variability is an inherent uncertainty of soil properties. Current reliability analyses generally incorporate random field theory and Monte Carlo simulation (MCS) when dealing with spatial variability, in which the computational efficiency is a significant challenge. This paper proposes a KL-FORM algorithm to improve the computational efficiency. In the proposed KL-FORM, Karhunen-Loeve (KL) expansion is used for discretizing random fields, and first-order reliability method (FORM) is employed for reliability analysis. The KL expansion and FORM can be used in conjunction, through adopting independent standard normal variables in the discretization of KL expansion as the basic variables in the FORM. To illustrate the effectiveness of this KL-FORM, it is applied to a case study of a strip footing in spatially variable unsaturated soil under rainfall, in which the bearing capacity of the footing is computed by numerical simulation. This case study shows that the KL-FORM is accurate and efficient. The parametric analyses suggest that ignoring the spatial variability of the soil may lead to an underestimation of the reliability index of the footing.","PeriodicalId":12602,"journal":{"name":"Geomechanics and Engineering","volume":null,"pages":null},"PeriodicalIF":3.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66472134","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Theoretical model for the shear strength of rock discontinuities with non-associated flow laws 具有非关联流动规律的岩石结构面抗剪强度的理论模型

IF 3.2 3区工程技术

Geomechanics and Engineering Pub Date : 2021-01-01 DOI: 10.12989/GAE.2021.24.4.307

R. Galindo, Jose Andres, A. Lara, Bin Xu, Z. Cao, Yuanqiang Cai

{"title":"Theoretical model for the shear strength of rock discontinuities with non-associated flow laws","authors":"R. Galindo, Jose Andres, A. Lara, Bin Xu, Z. Cao, Yuanqiang Cai","doi":"10.12989/GAE.2021.24.4.307","DOIUrl":"https://doi.org/10.12989/GAE.2021.24.4.307","url":null,"abstract":"In an earlier publication (Serrano et al. 2014), the theoretical basis for evaluating the shear strength in rock joints was presented and used to derive an equation that governs the relationship between tangential and normal stresses on the joint during slippage between the joint faces. In this paper, the theoretical equation is applied to two non-linear failure criteria by using non-associated flow laws, including the modified Hoek and Brown and modified Mohr-Coulomb equations. The theoretical model considers the geometric dilatancy, the instantaneous friction angle, and a parameter that considers joint surface roughness as dependent variables. This model uses a similar equation structure to the empirical law that was proposed by Barton in 1973. However, a good correlation with the empirical values and, therefore, Barton's equation is necessary to incorporate a non-associated flow law that governs breakage processes in rock masses and becomes more significant in highly fractured media, which can be induced in a rock joint. A linear law of dilatancy is used to assess the importance of the non-associated flow to obtain very close values for different roughness states, so the best results are obtained for null material dilatancy, which considers significant changes that correspond to soft rock masses or altered zones of weakness.","PeriodicalId":12602,"journal":{"name":"Geomechanics and Engineering","volume":null,"pages":null},"PeriodicalIF":3.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66472628","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Evaluation of failure mode of tunnel-type anchorage for a suspension bridge via scaled model tests and image processing 基于比例模型试验和图像处理的悬索桥隧道型锚固破坏模式评价

IF 3.2 3区工程技术

Geomechanics and Engineering Pub Date : 2021-01-01 DOI: 10.12989/GAE.2021.24.5.457

S. Seo, H. Lim, M. Chung

{"title":"Evaluation of failure mode of tunnel-type anchorage for a suspension bridge via scaled model tests and image processing","authors":"S. Seo, H. Lim, M. Chung","doi":"10.12989/GAE.2021.24.5.457","DOIUrl":"https://doi.org/10.12989/GAE.2021.24.5.457","url":null,"abstract":"In this study, the pull-out behavior of a tunnel-type anchorage for suspension bridges was investigated using experimental tests and image processing analyses. The study focused on evaluating the initial failure behavior and failure mode of the tunnel-type anchorage. In order to evaluate the failure mode of tunnel-type anchorage, a series of scaled model tests were conducted based on the prototype anchorage of the Ulsan Grand Bridge. In the model tests, the anchorage body and surrounding rocks were fabricated using a gypsum mixture. The pull-out behavior was investigated under plane strain conditions. The results of the model tests demonstrate that the tunnel-type anchorage underwent a wedge-shaped failure. In addition, the failure mode changed according to the differences in the physical properties of the surrounding rock and the anchorage body and the size of the anchor plate. The size of the anchor plate was found to be an important parameter that determines the failure mode. However, the difference in physical properties between the surrounding rock and the anchorage body did not affect its size. In addition, this study analyzed the initial failure behavior of the tunnel-type anchorage through image analysis and confirmed that the failure was sequentially transferred from the inside of the tunnel to the surrounding rock according to the image analysis. The reasonable failure mode for the design of the tunnel-type anchorage should be wedge-type rather than pull-out type.","PeriodicalId":12602,"journal":{"name":"Geomechanics and Engineering","volume":null,"pages":null},"PeriodicalIF":3.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66475090","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Effects of dry density and water content on compressibility and shear strength of loess 干密度和含水量对黄土压缩性和抗剪强度的影响

IF 3.2 3区工程技术

Geomechanics and Engineering Pub Date : 2021-01-01 DOI: 10.12989/GAE.2021.24.5.419

Ye-xia Guo, W. Ni, Haisong Liu

{"title":"Effects of dry density and water content on compressibility and shear strength of loess","authors":"Ye-xia Guo, W. Ni, Haisong Liu","doi":"10.12989/GAE.2021.24.5.419","DOIUrl":"https://doi.org/10.12989/GAE.2021.24.5.419","url":null,"abstract":"Investigation on the compressibility and shear strength of compacted loess is of great importance for the design and operation of engineering infrastructures in filling area. In this study, the mechanical behaviors of Yan'an compacted loess are investigated at various dry densities and water contents by conducting one dimensional compression and direct shear tests. And the elastic compressibility, plastic compressibility, yield stress and strength are obtained from the experiments. Results show that when water content increases, plastic compressibility parameter increases, but yield stress decreases. However, the increase of dry density leads to a decrease in plastic compressibility parameter but an increase in yield stress. In addition, elastic compressibility parameter is found to be a constant which is irrelevant to water content and dry density. As for strength, cohesion and internal friction angle is directly proportional to dry density, but inversely proportional to water content. Moreover, the mercury intrusion porosimetry (MIP) and scanning electron microscope (SEM) tests were also performed to observe the pore size distribution and microstructure of the specimens. Finally, by using results of MIP and SEM tests, the compressibility and strength behaviours of Yan'an compacted loess are explained from the perspective of pore-size distribution and microstructure.","PeriodicalId":12602,"journal":{"name":"Geomechanics and Engineering","volume":null,"pages":null},"PeriodicalIF":3.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66475363","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6

Deterministic and probabilistic analysis of tunnel face stability using support vector machine 基于支持向量机的巷道工作面稳定性确定性与概率分析

IF 3.2 3区工程技术

Geomechanics and Engineering Pub Date : 2021-01-01 DOI: 10.12989/GAE.2021.25.1.017

Bin Li, Yong Fu, Yi Hong, Zijun Cao

{"title":"Deterministic and probabilistic analysis of tunnel face stability using support vector machine","authors":"Bin Li, Yong Fu, Yi Hong, Zijun Cao","doi":"10.12989/GAE.2021.25.1.017","DOIUrl":"https://doi.org/10.12989/GAE.2021.25.1.017","url":null,"abstract":"This paper develops a convenient approach for deterministic and probabilistic evaluations of tunnel face stability using support vector machine classifiers. The proposed method is comprised of two major steps, i.e., construction of the training dataset and determination of instance-based classifiers. In step one, the orthogonal design is utilized to produce representative samples after the ranges and levels of the factors that influence tunnel face stability are specified. The training dataset is then labeled by two-dimensional strength reduction analyses embedded within OptumG2. For any unknown instance, the second step applies the training dataset for classification, which is achieved by an ad hoc Python program. The classification of unknown samples starts with selection of instance-based training samples using the k-nearest neighbors algorithm, followed by the construction of an instance-based SVM-KNN classifier. It eventually provides labels of the unknown instances, avoiding calculate its corresponding performance function. Probabilistic evaluations are performed by Monte Carlo simulation based on the SVM-KNN classifier. The ratio of the number of unstable samples to the total number of simulated samples is computed and is taken as the failure probability, which is validated and compared with the response surface method.","PeriodicalId":12602,"journal":{"name":"Geomechanics and Engineering","volume":null,"pages":null},"PeriodicalIF":3.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66475491","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4