Canadian Geotechnical Journal最新文献_第5页

Laboratory and numerical analyses on polyurethane-scrap rubber reinforced base layer 聚氨酯废橡胶加固基层的实验室和数值分析

Canadian Geotechnical Journal Pub Date : 2024-01-19 DOI: 10.1139/cgj-2023-0583

M. A. Farooq, Sanjay Nimbalkar

{"title":"Laboratory and numerical analyses on polyurethane-scrap rubber reinforced base layer","authors":"M. A. Farooq, Sanjay Nimbalkar","doi":"10.1139/cgj-2023-0583","DOIUrl":"https://doi.org/10.1139/cgj-2023-0583","url":null,"abstract":"Previous studies have explored using scrap rubber in constructing the ballasted track and showed tremendous potential to mitigate noise and vibration. However, its application for slab tracks has not been extensively investigated. This study intends to utilise scrap rubber in the base layer of the slab track; however, the high stress below base layer of the slab track may render its use unsuitable. The addition of scrap rubber would improve the damping performance but reduce the elastic modulus and cause excessive settlement of the track. This paper utilises an experimental programme comprising static and cyclic triaxial testing and numerical analyses to assess the suitability of four mixes, viz. mix-A (soil), mix-B (soil mixed with rubber), mix-C (polyurethane-treated soil), and mix-D (polyurethane-treated soil mixed with rubber), as a base layer in slab tracks. The laboratory investigations reveal that the best performance in terms of improved damping ratio and resilient modulus, and lowered excess pore water pressure and vertical strains are shown by mix-D. These experimental test findings were supplemented with the results from three-dimensional full-scale finite element analyses, which showed a drastic reduction in the vibration levels of the track with mix-D as a base layer instead of conventional lean-mix concrete.","PeriodicalId":505159,"journal":{"name":"Canadian Geotechnical Journal","volume":"97 50","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139612662","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

Understanding effects from overburden drilling of piles – a rational approach to reduce the impacts on the surroundings 了解堆积层钻孔的影响--减少对周围环境的影响的合理方法

Canadian Geotechnical Journal Pub Date : 2024-01-18 DOI: 10.1139/cgj-2023-0404

E. Lande, Stefan Ritter, Kjell Karlsrud, S. Nordal

{"title":"Understanding effects from overburden drilling of piles – a rational approach to reduce the impacts on the surroundings","authors":"E. Lande, Stefan Ritter, Kjell Karlsrud, S. Nordal","doi":"10.1139/cgj-2023-0404","DOIUrl":"https://doi.org/10.1139/cgj-2023-0404","url":null,"abstract":"This paper presents two case studies dealing with undesirable impacts of overburden drilling of casings for end bearing piles to bedrock. Monitored pore-water pressures and ground settlements are used to document and assess the influence from rotary percussive drilling with \"down-the-hole\" (DTH) hammers. The studies show that drilling with high-pressure air driven DTH hammers may cause considerable erosion and soil volume loss adjacent to the drill bit and along the casing resulting in settlements of the surrounding ground. The risk of soil volume loss increases when the drilling is carried out in erodible soils like silt and fine sands. The volume loss is found to be caused by a combined air-lift pump effect and a Venturi suction effect. Monitoring pore pressures in the vicinity of the drilling may be used to reduce soil volume loss and prevent damaging settlements. Results from drilling with water-driven DTH hammer showed significantly less ground settlements and influence on pore pressures compared to using an air-driven hammer. The study suggests that the drilling parameters flow rate and penetration rate, and the cross-sectional area of the pile casing can be combined in a non-dimensional methodology to assess the mass balance of drill cuttings when drilling with water flushing. A design framework is suggested to guide overburden drilling in urban settings to reduce potential impact on the surroundings.","PeriodicalId":505159,"journal":{"name":"Canadian Geotechnical Journal","volume":"120 38","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139613961","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

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

A novel three-dimensional SCR motion simulator for modelling the catenary riser–seabed interaction in a centrifuge 用于模拟离心机中导管立管与海底相互作用的新型三维 SCR 运动模拟器

Canadian Geotechnical Journal Pub Date : 2024-01-17 DOI: 10.1139/cgj-2023-0406

C.W.W. Ng, Yi Le, Sina Baghbanrezvan, Paul Van Laak

{"title":"A novel three-dimensional SCR motion simulator for modelling the catenary riser–seabed interaction in a centrifuge","authors":"C.W.W. Ng, Yi Le, Sina Baghbanrezvan, Paul Van Laak","doi":"10.1139/cgj-2023-0406","DOIUrl":"https://doi.org/10.1139/cgj-2023-0406","url":null,"abstract":"Steel catenary risers (SCRs) provide a cost-effective solution for deepwater oil and gas production. However, SCRs are susceptible to potential fatigue failure due to the cyclic motions of floating platforms. Previous studies on the physical modelling of cyclic SCR–seabed interactions have primarily focused on either the continuous cyclic motion of an SCR or a single rest period between two SCR motion packets. However, our understanding of the development of seabed trenches and excess pore pressure and their effects on SCR fatigue during multiple episodes of SCR motion and soil reconsolidation remains limited. This study presents a newly developed model container capable of modelling three-dimensional (3D) SCR motions including heave, surge, sway, and vortex-induced vibration (VIV) in a geotechnical centrifuge. A centrifuge test is conducted to investigate the vertical cyclic SCR–seabed interaction, considering five vertical cyclic motion packets with intervening periods of reconsolidation. The results indicate that ignoring the effects of reconsolidation leads to an overestimation of the fatigue life of an SCR. In this test, the SCR fatigue life is reduced by 18%–23% after five episodic SCR motion packets and intervening reconsolidation.","PeriodicalId":505159,"journal":{"name":"Canadian Geotechnical Journal","volume":" 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139617049","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

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

Bidirectional static loading tests on barrette piles. A case history from Ho Chi Minh City, Vietnam 巴氏桩双向静力加载试验。越南胡志明市的一个案例

Canadian Geotechnical Journal Pub Date : 2024-01-10 DOI: 10.1139/cgj-2023-0098

Tan Nguyen, B. Fellenius

{"title":"Bidirectional static loading tests on barrette piles. A case history from Ho Chi Minh City, Vietnam","authors":"Tan Nguyen, B. Fellenius","doi":"10.1139/cgj-2023-0098","DOIUrl":"https://doi.org/10.1139/cgj-2023-0098","url":null,"abstract":"Bi-directional static loading tests were conducted on two, strain-gage instrumented barrettes installed to 72 m depth in HoChiMinhCity, Vietnam. The barrettes were to support a 16 storey building with 5 basements. The soil profile comprised layers of medium coarse to fine sand, medium clay, firm to stiff clayey soil, and dense sandy silt. The region is experiencing an ongoing land subsidence affecting the upper about 40 m of soil and, on average in the city, the ground surface is currently settling 16 mm/year. The test records were processed by means of effective stress analysis to provide the axial pile force distribution, load transfer functions, and equivalent head-down load-movement curve. The analysis was then used to obtain the equivalent pile-head load-movement response adjusted to the planned 22 m deep basement excavation. Load transfer functions were back-calculated from the test records and indicate that the construction will show somewhat large load-transfer movement. However, because the neutral plane will be below the subsiding layers, below 40 m depth, downdrag is not expected to affect the building. The load response of the barrettes is compared to the results of a BD loading test on a 1.8 m diameter bored pile at an adjacent project.","PeriodicalId":505159,"journal":{"name":"Canadian Geotechnical Journal","volume":"5 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139439326","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