Canadian Geotechnical Journal最新文献_第4页

Degradation Mechanisms of Soil Arching under a Localized Cyclic Surface Loading 局部循环地表载荷下土壤拱起的退化机理

Canadian Geotechnical Journal Pub Date : 2024-01-17 DOI: 10.1139/cgj-2023-0150

Feng-Juan Tao, G. Ye, Zhen Zhang, Jie Han, Rongjun Zhang, Liu Liu

{"title":"Degradation Mechanisms of Soil Arching under a Localized Cyclic Surface Loading","authors":"Feng-Juan Tao, G. Ye, Zhen Zhang, Jie Han, Rongjun Zhang, Liu Liu","doi":"10.1139/cgj-2023-0150","DOIUrl":"https://doi.org/10.1139/cgj-2023-0150","url":null,"abstract":"Soil arching causes stress redistribution in many earth structures, such as pile-supported embankments and buried structures. A localized cyclic surface load (e.g., footing and traffic load) would weaken the arching effect and cause structural safety at potential risk. This paper presents a series of trapdoor tests using transparent soil to investigate the degradation mechanisms of soil arching subjected to a localized cyclic surface load. The particle image velocimetry (PIV) technique was adopted to monitor the inner soil deformations during test. The test results show that soil arching under localized cyclic surface loading first degraded locally on the trapdoor center and then progressed from the center to the entire trapdoor. The soil arching degraded faster within a lower backfill, on a wider trapdoor, and under a higher load frequency of localized surface loading. Owing to the volumetric expansion during trapdoor movement, the average vertical stress with soil arching increased faster under localized surface loading than that without soil arching. After full degradation of soil arching, the stress increment and vertical displacement contours with and without arching effect gradually tended to be similar. Finally, an empirical method was proposed to predict the soil arching ratio under localized cyclic surface loading.","PeriodicalId":505159,"journal":{"name":"Canadian Geotechnical Journal","volume":" 438","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139617803","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A new mathematical model for the estimation of shear modulus for unsaturated compacted soils 估算非饱和压实土壤剪切模量的新数学模型

Canadian Geotechnical Journal Pub Date : 2024-01-17 DOI: 10.1139/cgj-2023-0409

Q. Zhai, Ruize Zhang, H. Rahardjo, A. Satyanaga, Guoliang Dai, Weiming Gong, Xue-Liang Zhao, Chua Yuan Shen

引用次数: 0

Centrifuge and analytical modeling of counterweight retaining walls under translation mode 平移模式下配重挡土墙的离心机和分析建模

Canadian Geotechnical Journal Pub Date : 2024-01-17 DOI: 10.1139/cgj-2023-0124

Tengfei Wang, Q. Luo, M. H. El Naggar, Hongyang Liu, Kaiwen Liu

{"title":"Centrifuge and analytical modeling of counterweight retaining walls under translation mode","authors":"Tengfei Wang, Q. Luo, M. H. El Naggar, Hongyang Liu, Kaiwen Liu","doi":"10.1139/cgj-2023-0124","DOIUrl":"https://doi.org/10.1139/cgj-2023-0124","url":null,"abstract":"Counterweight retaining walls (CRWs) are a variant of gravity retaining walls that feature a pressure relief platform (RP) on the backfill side to reduce total earth pressure, offering a cost-effective option compared to traditional forms. However, the intricate interactions between CRWs and backfill, coupled with the lack of clear design guidelines, have restricted their use. This study examines the behavior of CRWs in translation mode using three different centrifuge model tests, each with varying fill heights. Observations show a slightly concave slip surface through the wall heel, and a nearly planar slip surface extending from the edge of the RP to the back of the wall in an active limit state. Backfill movement can be classified into translation, sliding, and stable zones. Earth pressure distribution on the upper wall follows a trapezoidal pattern, whereas the pressure on the lower wall exhibits a triangular distribution. Earth pressure on the RP is approximately linear, peaking near the RP's edge. Introducing a friction angle mobilization factor for the potential first slip surface improves accuracy in calculating earth pressure. The tests were replicated to validate the analytical model for earth pressure calculations, using the adaptive finite-element limit analysis method.","PeriodicalId":505159,"journal":{"name":"Canadian Geotechnical Journal","volume":" 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139616799","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Estimation of the installation torque-capacity correlation of helical pile considering spatially variable clays 考虑到粘土的空间变化，估算螺旋桩的安装扭矩与承载力的相关性

Canadian Geotechnical Journal Pub Date : 2024-01-12 DOI: 10.1139/cgj-2023-0331

Po Cheng, Fei Liu, Xuejian Chen, Yuhe Zhang, Kai Yao

{"title":"Estimation of the installation torque-capacity correlation of helical pile considering spatially variable clays","authors":"Po Cheng, Fei Liu, Xuejian Chen, Yuhe Zhang, Kai Yao","doi":"10.1139/cgj-2023-0331","DOIUrl":"https://doi.org/10.1139/cgj-2023-0331","url":null,"abstract":"As the offshore industry moves into deeper water, helical piles are emerging as a potential foundation solution option. A large number of studies have been published to explore the installation torque-capacity correlation. However, in most previous studies, the inherent spatial variability of soil strength was neglected. The present research explores the installation and extraction behavior of helical piles through a large deformation random finite element method. A strain-softening soil constitutive model proposed in past literature is employed to model the soil strength remoulding. The validity of the numerical model used to simulate the installation process and the subsequent uplift process is verified by the installation torque and the uplift capacity, respectively. The spatial variation of soil strength is modeled using random field, and then a series of Monte Carlo simulations are performed to investigate the torque-capacity correlation of the helical piles under different random realizations. The analysis results show that for the helical piles with different penetration depths, the spatially random soil strength markedly affects the torque-capacity correlation. Moreover, a probabilistic analysis of the torque-capacity correlation is conducted, which may be of great interest to engineering practitioners in the design method of the helical pile.","PeriodicalId":505159,"journal":{"name":"Canadian Geotechnical Journal","volume":" 12","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139624351","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Suction and anisotropy effects on the stiffness characteristics of a compacted lateritic clay from small to large strains 吸力和各向异性对压实红土粘土从小幅应变到大幅应变的刚度特性的影响

Canadian Geotechnical Journal Pub Date : 2024-01-12 DOI: 10.1139/cgj-2023-0295

O. T. Bentil, Chao Zhou

{"title":"Suction and anisotropy effects on the stiffness characteristics of a compacted lateritic clay from small to large strains","authors":"O. T. Bentil, Chao Zhou","doi":"10.1139/cgj-2023-0295","DOIUrl":"https://doi.org/10.1139/cgj-2023-0295","url":null,"abstract":"Lateritic clay has distinct properties from other clays due to its high sesquioxide content. Its stiffness characteristics have not been well understood, especially when the soil is unsaturated and anisotropic. This study investigated the stiffness characteristics of compacted lateritic clay through suction-controlled triaxial compression tests equipped with local strain measurements. Both vertically and horizontally cut specimens were tested to determine the evolution of stiffness anisotropy during shearing. Three suctions (0, 10 and 150 kPa) and two confining pressures (50 and 200 kPa) were considered. When strains are relatively small (e.g., less than 0.2%), the secant Young’s modulus Esec of vertical specimens is consistently higher than that of horizontal specimens at all suctions and stresses due to the inherent anisotropic structure. The degree of anisotropy increases with increasing suction since suction enhances the stiffness significantly more in vertical specimens than in horizontal specimens. This behaviour may be due to an enhanced force chain in the vertical direction during shearing. As strains increase, the degradation of Esec normalized by the maximum Young’s modulus E0 is almost independent of suction and anisotropy. Lateritic clay has a higher degradation rate than other clays with a similar plasticity index because of its aggregated microstructure.","PeriodicalId":505159,"journal":{"name":"Canadian Geotechnical Journal","volume":" 23","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139624549","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Vertical seismic response of end-bearing piles in nearly-saturated soil 近饱和土壤中端承桩的垂直地震响应

Canadian Geotechnical Journal Pub Date : 2024-01-10 DOI: 10.1139/cgj-2023-0294

Changjie Zheng, Jingquan Yang, G. Kouretzis, Xuanming Ding

引用次数: 0

Compaction, strength, and volume change characteristics of excavated clayey soil stabilized with composite admixture of cement and autoclaved aerated concrete powder 使用水泥和蒸压加气混凝土粉复合外加剂稳定的挖掘粘土的压实度、强度和体积变化特性

Canadian Geotechnical Journal Pub Date : 2024-01-10 DOI: 10.1139/cgj-2023-0352

Ziang Wang, Tony Liang-Tong Zhan, Haihua Zhang, Liangfeng Zheng, Ting Kang

{"title":"Compaction, strength, and volume change characteristics of excavated clayey soil stabilized with composite admixture of cement and autoclaved aerated concrete powder","authors":"Ziang Wang, Tony Liang-Tong Zhan, Haihua Zhang, Liangfeng Zheng, Ting Kang","doi":"10.1139/cgj-2023-0352","DOIUrl":"https://doi.org/10.1139/cgj-2023-0352","url":null,"abstract":"Low-strength and highly compressible excavated clayey soils are common in geotechnical engineering, which cannot serve as a bearing stratum and typically end up being disposed of in landfills. Autoclaved aerated concrete powder (AACP) is a lightweight and porous waste material, with its stockpiles rapidly accumulating worldwide. To promote sustainable development in geotechnical engineering, a type of composite admixture consisting of cement and AACP was developed to modify clayey soils in this study. The physical and mechanical properties of untreated and the composite admixture-treated soil samples were investigated via Atterberg limits, compaction, bender element, constraint compression, free swell, and unconfined compressive strength (UCS) tests. The physicochemical and microstructural observations, including soil pH, SEM, and MIP analyses, were conducted to interpret the macroscopic mechanical behaviors. Test results showed that the incorporation of AACP improved the workability of clayey soils, while cement further enhanced their mechanical properties. Hydration compounds primarily filled the voids with a diameter ranging from 0.1 to 1 μm. From the perspective of volume change behavior, 8% cement content was recommended. Shear wave velocity showed a strong correlation with the UCS, demonstrating that the bender element technique was an effective non-destructive tool for assessing the strength of compacted samples.","PeriodicalId":505159,"journal":{"name":"Canadian Geotechnical Journal","volume":"37 10","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139441384","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The influence of viscous behavior and static shear stress on the cyclic strengths of plastic soils: a numerical study 粘性行为和静态剪应力对塑性土壤循环强度的影响：数值研究

Canadian Geotechnical Journal Pub Date : 2024-01-09 DOI: 10.1139/cgj-2023-0060

Tyler J. Oathes, Trevor Carey

{"title":"The influence of viscous behavior and static shear stress on the cyclic strengths of plastic soils: a numerical study","authors":"Tyler J. Oathes, Trevor Carey","doi":"10.1139/cgj-2023-0060","DOIUrl":"https://doi.org/10.1139/cgj-2023-0060","url":null,"abstract":"An accurate understanding of the cyclic behavior of clays and plastic silts is important for system performance predictions during earthquake loading. This paper presents the results of a numerical investigation into the individual and combined influences of static shear stress and viscous strength gain on the cyclic resistance of clays and plastic silts. Using the viscoplastic constitutive model PM4SiltR implemented in the finite difference program FLAC 8.1, the cyclic behaviors of the plastic soils were simulated using single-element cyclic direct simple shear simulations. A parametric analysis was performed with different combinations of viscous strength gains and static shear stresses. The effects of static shear stress and viscous strength gain varied under monotonic and cyclic loading conditions. Empirical correlations developed using scant laboratory data may not accurately predict the reduction of cyclic strengths with increasing static shear stress. Furthermore, sizeable magnitudes of monotonic viscous strength gains only produced a marginal increase in cyclic strengths. The findings from this study highlight the need for future experimental laboratory testing to validate the numerical findings, in order to improve the accuracy of performance predictions of geosystems constructed with clays and plastic silts during and following earthquake loading.","PeriodicalId":505159,"journal":{"name":"Canadian Geotechnical Journal","volume":"17 12","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139443785","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Research on energy-absorption active control method for large deformation of tunnel surrounding rock through multi-fault fracture zone 穿越多断层破碎带隧道围岩大变形能量吸收主动控制方法研究

Canadian Geotechnical Journal Pub Date : 2024-01-08 DOI: 10.1139/cgj-2023-0318

Zhigang Tao, Yuting Mao, Jihao Sun, Xiaoyun Zhang, SS. Huo, Manchao He

{"title":"Research on energy-absorption active control method for large deformation of tunnel surrounding rock through multi-fault fracture zone","authors":"Zhigang Tao, Yuting Mao, Jihao Sun, Xiaoyun Zhang, SS. Huo, Manchao He","doi":"10.1139/cgj-2023-0318","DOIUrl":"https://doi.org/10.1139/cgj-2023-0318","url":null,"abstract":"In order to study the problems of large deformation of surrounding rock and water-rich dense fracture zones during tunnel construction through fault fracture zone, the NPR anchor cable control method is studied based on the Tabaiyi tunnel. Firstly, the mechanical deformation mechanism of surrounding rock is analyzed by geological conditions, lithology and strength of surrounding rock, and different surrounding rock zones are obtained. Then, based on the self-developed high-prestressed NPR anchor cable, the tunnel prevention and control measures are designed. The high stress NPR anchor net technology is used to support the common large deformation and fault fracture zone, while in the water-rich dense fracture zones, the combined support of double gradient grouting technology and high stress NPR anchor net technology is adopted. Finally, in order to evaluate the control effect of the support design scheme, the deformation of surrounding rock, the axial force of NPR anchor cable and the pressure of steel arch are monitored in real time. The results show that the high stress NPR anchor net technology can effectively control the large deformation of tunnel surrounding rock caused by fault zone. And in the water-rich zones, the double gradient grouting technology can provide sufficient anchoring force for the NPR anchor cable. The two technologies control the maximum deformation of surrounding rock within 300 mm, and realize the stability of tunnel primary support.","PeriodicalId":505159,"journal":{"name":"Canadian Geotechnical Journal","volume":"29 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139447542","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0