期刊文献+

二次检索

题名
关键词
文摘
作者
第一作者
机构
刊名
分类号
参考文献
作者简介
基金资助
栏目信息
共找到1,769篇文章
< 1 2 89 >
每页显示 20 50 100
A new approach for time effect analysis of settlement for single pile based on virtual soil-pile model 被引量:9
1
作者 吴文兵 王奎华 +1 位作者 张智卿 CHIN Jian Leo 《Journal of Central South University》 SCIE EI CAS 2012年第9期2656-2662,共7页
A new approach is proposed to analyze the settlement behavior for single pile embedded in layered soils. Firstly, soil layers surrounding pile shaft are simulated by using distributed Voigt model, and finite soil laye... A new approach is proposed to analyze the settlement behavior for single pile embedded in layered soils. Firstly, soil layers surrounding pile shaft are simulated by using distributed Voigt model, and finite soil layers under the pile end are assumed to be virtual soil-pile whose cross-section area is the same as that of the pile shaft. Then, by means of Laplace transform and impedance function transfer method to solve the static equilibrium equation of pile, the analytical solution of the displacement impedance fimction at the pile head is derived. Furthermore, the analytical solution of the settlement at the head of single pile is theoretically derived by virtue of convolution theorem. Based on these solutions, the influences of parameters of soil-pile system on the settlement behavior for single pile are analyzed. Also, comparison of the load-settlement response for two well-instrumented field tests in multilayered soils is given to demonstrate the effectiveness and accuracy of the proposed approach. It can be noted that the presented solution can be used to calculate the settlement of single pile for the preliminary design of pile foundation. 展开更多
关键词 SETTLEMENT time effect single pile virtual soil-pile model layered soil VISCOELASTICITY distributed Voigt model
下载PDF
Model tests and numerical analyses on horizontal impedance functions of inclined single piles embedded in cohesionless soil 被引量:2
2
作者 Chandra Shekhar Goit Masato Saitoh 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2013年第1期143-154,共12页
Horizontal impedance functions of inclined single piles are measured experimentally for model soil-pile systems with both the effects of local soil nonlinearity and resonant characteristics.Two practical pile inclinat... Horizontal impedance functions of inclined single piles are measured experimentally for model soil-pile systems with both the effects of local soil nonlinearity and resonant characteristics.Two practical pile inclinations of 5掳 and 10掳 in addition to a vertical pile embedded in cohesionless soil and subjected to lateral harmonic pile head loadings for a wide range of frequencies are considered.Results obtained with low-to-high amplitude of lateral loadings on model soil-pile systems encased in a laminar shear box show that the local nonlinearities have a profound impact on the horizontal impedance functions of piles.Horizontal impedance functions of inclined piles are found to be smaller than the vertical pile and the values decrease as the angle of pile inclination increases.Distinct values of horizontal impedance functions are obtained for the 'positive' and 'negative' cycles of harmonic loadings,leading to asymmetric force-displacement relationships for the inclined piles.Validation of these experimental results is carried out through three-dimensional nonlinear finite element analyses,and the results from the numerical models are in good agreement with the experimental data.Sensitivity analyses conducted on the numerical models suggest that the consideration of local nonlinearity at the vicinity of the soil-pile interface influence the response of the soil-pile systems. 展开更多
关键词 inclined single piles harmonic loads horizontal impedance functions local nonlinearity finite element model
下载PDF
Experimental investigation on seismic behavior of single piles in sandy soil 被引量:1
3
作者 Werasak Raongjant 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2011年第3期417-422,共6页
This paper describes a quasi-static test program featuring lateral cyclic loading on single piles in sandy soil. The tests were conducted on 18 aluminum model piles with different cross sections and lateral load eccen... This paper describes a quasi-static test program featuring lateral cyclic loading on single piles in sandy soil. The tests were conducted on 18 aluminum model piles with different cross sections and lateral load eccentricity ratios, e/d, (e is the lateral load eccentricity and d is the diameter of pile) of 0, 4 and 8, embedded in sand with a relative density of 30% and 70%. The experimental results include lateral load-displacement hysteresis loops, skeleton curves and energy dissipation curves. Lateral capacity, ductility and energy dissipation capacity of single piles under seismic load were evaluated in detail. The lateral capacities and the energy dissipation capacity of piles in dense sand were much higher than in loose sand. When embedded in loose sand, the maximum lateral load and the maximum lateral displacement of piles increased as e/d increased. On the contrary, when embedded in dense sand, the maximum lateral load of piles decreased as e/d increased. Piles with a higher load eccentricity ratio experienced higher energy dissipation capacity than piles with e/d of 0 in both dense and loose sand. At a given level of displacement, piles with circular cross sections provided the best energy dissipation capacity in both loose and dense sand. 展开更多
关键词 seismic behavior single pile sandy soil load eccentricity ratio lateral resistance
下载PDF
Target reliability index for serviceability limit state of single piles 被引量:3
4
作者 边晓亚 郑俊杰 +1 位作者 徐志军 章荣军 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第1期310-316,共7页
The objective is to develop an approach for the determination of the target reliability index for serviceability limit state(SLS) of single piles. This contributes to conducting the SLS reliability-based design(RBD) o... The objective is to develop an approach for the determination of the target reliability index for serviceability limit state(SLS) of single piles. This contributes to conducting the SLS reliability-based design(RBD) of piles. Based on a two-parameter,hyperbolic curve-fitting equation describing the load-settlement relation of piles, the SLS model factor is defined. Then, taking into account the uncertainties of load-settlement model, load and bearing capacity of piles, the formula for computing the SLS reliability index(βsls) is obtained using the mean value first order second moment(MVFOSM) method. Meanwhile, the limit state function for conducting the SLS reliability analysis by the Monte Carlo simulation(MCS) method is established. These two methods are finally applied to determine the SLS target reliability index. Herein, the limiting tolerable settlement(slt) is treated as a random variable. For illustration, four load test databases from South Africa are compiled again to conduct reliability analysis and present the recommended target reliability indices. The results indicate that the MVFOSM method overestimates βsls compared to that computed by the MCS method. Besides, both factor of safety(FS) and slt are key factors influencing βsls, so the combination of FS and βsls is welcome to be used for the SLS reliability analysis of piles when slt is determined. For smaller slt, pile types and soils conditions have significant influence on the SLS target reliability indices; for larger slt, slt is the major factor having influence on the SLS target reliability indices. This proves that slt is the most key parameter for the determination of the SLS target reliability index. 展开更多
关键词 single pile serviceability limit state target reliability index mean value first order second moment method Monte Carlo simulation
下载PDF
Numerical simulation of frost jacking response of a single pile considering hydro-thermo-mechanical coupling
5
作者 XingYu Wang Dan Chang JianKun Liu 《Research in Cold and Arid Regions》 CSCD 2022年第5期307-316,共10页
Permafrost is widely distributed in China and around the world.In permafrost regions,soil frost heave and thawing are severe and frequent,and can destabilize pile foundations.To this end,a finite element model of a si... Permafrost is widely distributed in China and around the world.In permafrost regions,soil frost heave and thawing are severe and frequent,and can destabilize pile foundations.To this end,a finite element model of a single pile in frozen soil is established to investigate the frost heave and frost jacking response to ensure its safety in the Qinghai-Tibet Plateau.Firstly,a hydro-thermal coupling model of a single pile in frozen soil is established based on coupling parameters and initial and boundary conditions.Then the temperature and moisture distributions are analyzed through the established coupling model.A hydro-thermo-mechanical coupling model is developed by importing the ice content and temperature results.Simulation results indicate that the amount of frost heave is greater at locations closer to the ground surface,and the displacement is smaller for frozen soil that is closer to the side of the pile.The results on frost jacking behavior of piles from this study can serve as a reference for the design,construction and maintenance of foundations. 展开更多
关键词 single pile Frozen soil Hydro-thermo-mechanical coupling Frost jacking
下载PDF
Experimental study and numerical analysis on bearing behaviors of super-long rock-socketed bored pile groups 被引量:2
6
作者 高睿 胡念 朱斌 《Journal of Southeast University(English Edition)》 EI CAS 2010年第4期597-602,共6页
A centrifuge modeling test and a three-dimensional finite element analysis(FEA)of super-long rock-socketed bored pile groups of the Tianxingzhou Bridge are proposed.Based on the similarity theory,different prototypi... A centrifuge modeling test and a three-dimensional finite element analysis(FEA)of super-long rock-socketed bored pile groups of the Tianxingzhou Bridge are proposed.Based on the similarity theory,different prototypical materials are simulated using different indicators in the centrifuge model.The silver sand,the shaft and the pile cap are simulated according to the natural density,the compressive stiffness and the bending stiffness,respectively.The finite element method(FEM)is implemented and analyzed in ANSYS,in which the stress field during the undisturbed soil stage,the boring stage,the concrete-casting stage and the curing stage are discussed in detail.Comparisons in terms of load-settlement,shaft axial force distribution and lateral friction between the numerical results and the test data are carried out to investigate the bearing behaviors of super-long rock-socketed bored pile groups under loading and unloading conditions.Results show that there is a good agreement between the centrifuge modeling tests and the FEM.In addition,the load distribution at the pile top is complicated,which is related to the stiffness of the cap,the corresponding assumptions and the analysis method.The shaft axial force first increases slightly with depth then decreases sharply,and the rate of decrease in rock is greater than that in sand and soil. 展开更多
关键词 super-long rock-socketed pile bored pile groups centrifuge modeling test finite element analysis
下载PDF
Axial bearing behavior of super-long piles in deep soft clay over stiff layers 被引量:3
7
作者 邹新军 赵明华 《Journal of Central South University》 SCIE EI CAS 2013年第7期2008-2016,共9页
In order to find out the bearing behavior of super-long piles located in deep soft clay over stiff layers around Dongting Lake, China, a test pile was first designed with the field loading test finished afterward. Bas... In order to find out the bearing behavior of super-long piles located in deep soft clay over stiff layers around Dongting Lake, China, a test pile was first designed with the field loading test finished afterward. Based on the measured test results, load transfer mechanism and bearing behavior of the pile shaft were discussed in detail. Then, by introducing a bi-linear model for shaft friction and the tri-linear model for pile tip resistance, respectively, the governing differential equation of pile soil system was set up by the load transfer method with the analytical solutions derived as well, taking into account the effect by stratified feature and various bearing conditions of subsoil, material nonlinearity, and the sediment under pile tip. Furthermore, formulas to determine the axial capacity of super-long piles by the pile top settlement were advised and applied to analyze the test pile. Good agreement between the predicted load settlement variations and the measured data is obtained to verify the validity of the present method. The results also show that, the axial bearing capacity of super-long piles should be controlled by the allowable pile top settlement, and buckling stability of the pile shaft should be paid attention as well. 展开更多
关键词 super-long pile SETTLEMENT load transfer model axial load capacity field test
下载PDF
Buckling analysis of super-long rock-socketed filling piles in soft soil area by element free Galerkin method 被引量:2
8
作者 邹新军 赵明华 刘光栋 《Journal of Central South University of Technology》 EI 2007年第6期858-863,共6页
In order to discuss the buckling stability of super-long rock-socketed filling piles widely used in bridge engineering in soft soil area such as Dongting Lake, the second stability type was adopted instead of traditio... In order to discuss the buckling stability of super-long rock-socketed filling piles widely used in bridge engineering in soft soil area such as Dongting Lake, the second stability type was adopted instead of traditional first type, and a newly invented numerical analysis method, i.e. the element-free Galerkin method (EFGM), was introduced to consider the non-concordant deformation and nonlinearity of the pile-soil interface. Then, based on the nonlinear elastic-ideal plastic pile-soil interface model, a nonlinear iterative algorithm was given to analyze the pile-soil interaction, and a program for buckling analysis of piles by the EFGM (PBAP-EFGM) and arc length method was worked out as well. The application results in an engineering example show that, the shape of pile top load-settlement curve obtained by the program agrees well with the measured one, of which the difference may be caused mainly by those uncertain factors such as possible initial defects of pile shaft and the eccentric loading during the test process. However, the calculated critical load is very close with the measured ultimate load of the test pile, and the corresponding relative error is only 5.6%, far better than the calculated values by linear and nonlinear incremental buckling analysis (with a greater relative error of 37.0% and 15.4% respectively), which also verifies the rationality and feasibility of the present method. 展开更多
关键词 super-long rock-socketed filling pile buckling analysis element free Galerkin method critical load
下载PDF
Dynamic Analysis of a Single-Column Platform
9
作者 Lian Gan , Ni Kan, Hu Kai and Guo Dawei Prof., Senior Engineer, Marine Design and Research Institute of China, Shanghai Senior Engineer, Marine Design and Research Institute of China, Shanghai Engineer, Marine Design and Research Institute of China, Shanghai 《China Ocean Engineering》 SCIE EI 1991年第4期385-394,共10页
In this paper, a single-column structure used as well-head platform is studied. The loads of wave and current exerted on the single-column will be greatly reduced, therefore the cost of the structure will be decreased... In this paper, a single-column structure used as well-head platform is studied. The loads of wave and current exerted on the single-column will be greatly reduced, therefore the cost of the structure will be decreased. The advantages of the single-column structure compared with ordinary jacket structure are explained. A dynamic analysis of this type of structure is made and some problems related to dynamic analysis are solved. In order to check the reliability of computation theory and programme, model tests have been carried out. However, as space is limited, the conclusion of tests will be introduced in another paper. Therefore, this type of structure is applicable for proctical engineering. 展开更多
关键词 single-column structure dynamic analysis diffraction wave theory natural period resonant dynamic strength damping ratio fictitious stiffness of pile top fatigue analysis
下载PDF
液化场地大直径变截面单桩动力响应研究 被引量:1
10
作者 冯忠居 段久琴 +3 位作者 张聪 林立华 赵瑞欣 王逸然 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第5期56-67,共12页
为研究不同地震动强度下液化场地大直径变截面单桩的动力响应规律,基于振动台试验,选取5010波,在地震动强度0.10g~0.45g作用下,研究液化场地砂土孔压比和大直径变截面单桩桩顶水平位移、桩身弯矩、桩身加速度时程响应及桩基损伤等变化规... 为研究不同地震动强度下液化场地大直径变截面单桩的动力响应规律,基于振动台试验,选取5010波,在地震动强度0.10g~0.45g作用下,研究液化场地砂土孔压比和大直径变截面单桩桩顶水平位移、桩身弯矩、桩身加速度时程响应及桩基损伤等变化规律.试验结果表明:饱和砂土孔压比随着地震动强度的增大上升明显,地震动强度≥0.30g时,饱和砂土孔压比稳定值在0.9附近,此时砂土完全液化;在0.45g地震动强度作用下,桩身加速度、桩顶水平位移及桩身弯矩均达到最大;桩身不同位置处加速度峰值出现时刻均滞后于输入地震波加速度峰值出现时刻,且桩顶及变截面的加速度响应比桩端的响应更弱;不同地震动强度作用下,桩身弯矩最大值均出现在液化土层和非液化土层分界处,且变截面处弯矩小于土层分界面处;地震动强度达到0.30g时,大直径变截面单桩桩身发生损伤.因此,液化场地下大直径变截面桥梁单桩基础抗震设计时,应该重点考虑饱和砂土层分界处、变截面处的抗弯能力,以确保单桩桩身强度满足抗震要求. 展开更多
关键词 岩土工程 变截面单桩 液化场地 动力响应 振动台试验 抗震设计
下载PDF
中风化花岗岩中嵌岩桩承载性能原位试验与极限承载力预测
11
作者 刘超 白晓宇 +3 位作者 银吉超 卫永辉 谭永明 孟德朝 《河北工程大学学报(自然科学版)》 CAS 2024年第3期49-58,共10页
为深入探究中风化花岗岩中嵌岩桩的竖向抗压承载特性,对12根嵌岩桩进行了单桩竖向抗压静载原位试验与ABAQUS有限元数值模拟,通过多种方法对嵌岩单桩极限承载力进行评价,明确中风化花岗岩中嵌岩桩竖向抗压承载性状。研究表明:12根中风化... 为深入探究中风化花岗岩中嵌岩桩的竖向抗压承载特性,对12根嵌岩桩进行了单桩竖向抗压静载原位试验与ABAQUS有限元数值模拟,通过多种方法对嵌岩单桩极限承载力进行评价,明确中风化花岗岩中嵌岩桩竖向抗压承载性状。研究表明:12根中风化花岗岩中嵌岩桩并非表现出完全端承桩,而是呈摩擦型桩或摩擦端承桩的性状;中风化花岗岩地基中的嵌岩桩竖向抗压极限承载力较高,桩顶沉降小,满足工程对基础的承载要求;有限元模拟荷载-沉降曲线与实测荷载-沉降曲线走势吻合度较高,桩顶沉降误差较小;本试验条件下,桩端阻力占桩顶荷载的56.9%,桩侧摩阻力占比为43.1%,桩侧摩阻力在荷载传递过程中发挥较充分;有限元模拟得到的单桩极限承载力与指数函数模型的预测结果较为吻合,可用于嵌岩桩单桩竖向抗压极限承载力的预测,以及嵌岩桩承载性状和荷载传递规律的分析。 展开更多
关键词 嵌岩桩 中风化花岗岩 承载性能 原位试验 单桩极限承载力预测 数值模拟
下载PDF
震陷场地变截面单桩动力特性与损伤评价
12
作者 张聪 冯忠居 +2 位作者 林路宇 周桂梅 陈露 《岩土力学》 EI CAS CSCD 北大核心 2024年第10期3037-3046,3057,共11页
为探明震陷场地变截面单桩动力响应特性与损伤状况,以翔安大桥为工程背景,基于大型振动台试验,开展了0.10g~0.45g地震动强度下变截面单桩动力响应特性的研究,评价分析了变截面单桩损伤程度。结果表明:受桩周软弱土层震陷特性的影响,变... 为探明震陷场地变截面单桩动力响应特性与损伤状况,以翔安大桥为工程背景,基于大型振动台试验,开展了0.10g~0.45g地震动强度下变截面单桩动力响应特性的研究,评价分析了变截面单桩损伤程度。结果表明:受桩周软弱土层震陷特性的影响,变截面单桩桩顶水平位移动力响应、桩身加速度动力响应及桩身弯矩动力响应均随地震动强度增大呈增大趋势,桩基基频逐渐减小;变截面单桩弯矩最大值出现在震陷土层分界处,地震动强度为0.30g时,超过了其抗弯承载力;地震动强度为0.20g时,变截面单桩桩顶水平位移、桩身加速度、桩身弯矩显著增大,桩基基频突降。基于系统损伤理论,震陷场地变截面单桩损伤状况分为稳定阶段、加剧损伤阶段、塑性破坏阶段共3个阶段。试验结束后,变截面位置处产生弯曲塑性破坏。 展开更多
关键词 桥梁工程 软土震陷 振动台试验 变截面单桩 动力响应
下载PDF
大直径嵌岩灌注桩承载特性试验与有限元模拟
13
作者 白晓宇 刁浩杰 +3 位作者 银吉超 桑松魁 张亚妹 张胜凯 《重庆交通大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第9期25-33,共9页
基于青岛某工程的4根大直径嵌岩灌注桩,在现场开展了单桩竖向抗压静载试验和桩身完整性测试,以明确大直径嵌岩灌注桩在竖向荷载下的承载特征,拟揭示不同荷载水平下嵌岩灌注桩的承载力发挥机制。结合不同嵌岩深度的单桩承载性能有限元模... 基于青岛某工程的4根大直径嵌岩灌注桩,在现场开展了单桩竖向抗压静载试验和桩身完整性测试,以明确大直径嵌岩灌注桩在竖向荷载下的承载特征,拟揭示不同荷载水平下嵌岩灌注桩的承载力发挥机制。结合不同嵌岩深度的单桩承载性能有限元模拟,重点分析了单桩在不同嵌岩深度下的竖向抗压承载特性和桩土位移分布特征。研究表明:在笔者试验条件下,大直径嵌岩灌注桩单桩竖向抗压承载力具有一定离散性,桩头部位的损坏会极大影响单桩承载力的有效发挥;加载完成后,数值模拟得到的桩顶沉降量为31.56 mm,约为现场实测值的1.1倍,模拟结果与实测结果较为吻合;通过不同嵌岩比的模拟结果对比发现,嵌岩深度越大桩端阻力占桩顶荷载的比例越小,且桩端阻力占比的变化速率随着嵌岩比的增加逐渐减缓;嵌岩深度取2.5倍桩径为宜。 展开更多
关键词 岩土工程 嵌岩桩 泥浆护壁成孔灌注桩 单桩竖向抗压承载力 承载力异常 现场试验 数值模拟
下载PDF
基于数值模拟的风化层单桩承载特性研究
14
作者 王粤 王飞 《山西建筑》 2024年第22期78-80,167,共4页
为了探究风化层中桩基承载特性,采用数值模拟技术建立了桩-土离散单元模型,对单桩的承载特性以及桩周土的细观力学行为进行了分析。结果表明单桩与周围土体之间存在复杂的相互作用,利用数值仿真计算可以得到桩周土的位移场和应力分布特... 为了探究风化层中桩基承载特性,采用数值模拟技术建立了桩-土离散单元模型,对单桩的承载特性以及桩周土的细观力学行为进行了分析。结果表明单桩与周围土体之间存在复杂的相互作用,利用数值仿真计算可以得到桩周土的位移场和应力分布特征;在荷载增加过程中,土体发生剪胀效应和应力集中,导致单桩承载性能衰减;单桩的承载性能随桩径增大而明显提高;桩周土的压缩系数在沉降值超过6 mm时发生突变,计算结果对于预测土体变形特性具有一定的指导意义。数值模拟结果为风化层中桩基的承载性能分析提供了理论支持。 展开更多
关键词 桩基础 单桩 承载性能 数值模拟 变形分析
下载PDF
厚软土层下高层建筑长短桩复合地基承载性能研究
15
作者 乔旭 《宁波工程学院学报》 2024年第3期56-62,共7页
为了提升厚软土层下高层建筑地基的承载力,提出长短桩复合地基承载性能研究。基于地质勘测结果设计长短桩复合地基,分析其承载性状及沉降情况;利用Mohr-Coulomb模型,完成承载性能模拟。实验结果显示:在短桩和长桩桩体的单桩承载载荷最大... 为了提升厚软土层下高层建筑地基的承载力,提出长短桩复合地基承载性能研究。基于地质勘测结果设计长短桩复合地基,分析其承载性状及沉降情况;利用Mohr-Coulomb模型,完成承载性能模拟。实验结果显示:在短桩和长桩桩体的单桩承载载荷最大时,沉降结果均在5.00 cm左右;楼体层高为30.00 m时,单位载荷沉降平均值为0.51 cm。所提方法能够可靠分析厚软土层的高层建筑长短桩复合地基承载性能,为厚软土层的高层建筑长短桩复合地基设计提供可靠依据。 展开更多
关键词 厚软土层 高层建筑 长短桩复合地基 土顶应力 单桩桩径
下载PDF
局部冲刷下砂土中桩-盘复合基础H-T联合承载特性
16
作者 邹新军 陈顺 +2 位作者 涂欣瑶 梁楚雄 杨紫健 《防灾减灾工程学报》 CSCD 北大核心 2024年第3期495-505,共11页
海上风机基础工作时既承受复杂组合荷载作用,也受波流冲刷影响。单桩-摩擦盘复合基础同时结合了单桩与重力式基础的特点,摩擦盘还可起防冲板作用。为探讨砂土地基中H-T联合作用时局部冲刷对这种复合基础承载特性的影响,首先基于室内水... 海上风机基础工作时既承受复杂组合荷载作用,也受波流冲刷影响。单桩-摩擦盘复合基础同时结合了单桩与重力式基础的特点,摩擦盘还可起防冲板作用。为探讨砂土地基中H-T联合作用时局部冲刷对这种复合基础承载特性的影响,首先基于室内水槽试验装置,完成了一系列模型载荷试验;获得了冲刷前后桩-盘复合基础的荷载-位移曲线,经无量纲化处理与曲线拟合,获得H-T联合受荷桩-盘复合基础的承载包络线及其简化计算公式。然后,采用有限元细化分析了主要冲刷参数(冲刷深度、冲刷宽度、冲刷角度)及加载点高度对复合基础承载特性的影响,结果表明:冲刷坑的存在使复合基础的横向及扭转抗力明显降低,削弱程度分别可达25%及45%;进一步分析表明,桩身弯矩值随加载点高度的增加而显著增大,随预加扭矩的增加呈下降趋势;局部冲刷会明显削弱复合基础的承载力,同时H-T联合作用时相应的承载力包络线向内发生不同程度的收缩;其中,冲刷深度的影响最大,对横向抗力与扭转抗力的削弱程度分别可达约35%及60%,冲刷角度次之,冲刷宽度的影响最小;此外,不同加载路径下桩-盘复合基础承载力包络线呈现一定程度的差异。 展开更多
关键词 海上风电基础 单桩-摩擦盘复合基础 局部冲刷 H-T联合作用 承载力包络线
下载PDF
青藏高原多年冻土区单桩受斜坡地基土原位冻胀影响下的力学特性研究 被引量:1
17
作者 姜来库 郭春香 +2 位作者 王小龙 杨迅 刘涛 《兰州交通大学学报》 CAS 2024年第1期24-32,共9页
在青藏高原多年冻土区铁路建设中,由于高原山区地形地貌复杂,建设在斜坡中的桩基础不在少数,地基土经历冻融过程以后桩基常常发生倾斜,严重影响铁路运行安全。为揭示在地基冻胀影响下多年冻土区斜坡单桩的倾斜机理,基于传热学与弹性力学... 在青藏高原多年冻土区铁路建设中,由于高原山区地形地貌复杂,建设在斜坡中的桩基础不在少数,地基土经历冻融过程以后桩基常常发生倾斜,严重影响铁路运行安全。为揭示在地基冻胀影响下多年冻土区斜坡单桩的倾斜机理,基于传热学与弹性力学,建立桩体体系热力耦合计算模型并进行室内试验验证计算模型的合理性,考虑地基土原位冻胀、水分相变、大气变暖等因素,进行地基土冻胀影响下斜坡桩基力学特性模拟分析。研究表明:斜坡桩体在地基土冻胀过程受到不均匀水平冻胀力、产生水平位移以及桩体弯矩,且水平位移随着地基斜坡坡度增大而增大;因不均匀水平冻胀引起的桩体应力占总应力的46.3%,对桩体安全性以及工程寿命产生较大影响。进行受到斜坡地基土冻胀影响下单桩力学特性分析,揭示在地基冻胀影响下多年冻土区斜坡单桩的倾斜机理,对多年冻土区斜坡桩基设计及运营有一定的参考价值。 展开更多
关键词 地基冻胀 水平位移 斜坡单桩 室内试验 倾斜机理 热力耦合
下载PDF
基于COMSOL的非饱和土中单桩垂直动力特性研究
18
作者 叶梓 陈永辉 +3 位作者 孔纲强 陈庚 徐洁 胡楠 《振动与冲击》 EI CSCD 北大核心 2024年第12期46-52,共7页
浅层地表存在大量的非饱和土,其动力特性与饱和介质或单相介质相比存在明显的差异,而这部分非饱和土常常是与单桩接触的主要材料,对单桩的动力行为影响显著。该文考虑动力受荷单桩周边土体的非饱和特性,基于非饱和多孔弹性介质的波动方... 浅层地表存在大量的非饱和土,其动力特性与饱和介质或单相介质相比存在明显的差异,而这部分非饱和土常常是与单桩接触的主要材料,对单桩的动力行为影响显著。该文考虑动力受荷单桩周边土体的非饱和特性,基于非饱和多孔弹性介质的波动方程、单桩运动方程与边界条件,利用多物理仿真软件COMSOL中的偏微分方程模块构建了非饱和土与单桩动力相互作用的数学模型,并考虑土的成层性、横观各向同性和纵向非均质性。在与现有文献对比验证COMSOL模型正确性后,设计多组数值算例,讨论土体饱和度、地层非均质性等因素对单桩垂直动力阻抗的影响。 展开更多
关键词 非饱和土 单桩基础 动力阻抗 COMSOL软件
下载PDF
考虑系泊点深度的单点系泊系统锚桩水平承载性能理论分析
19
作者 董恒年 孔纲强 +1 位作者 周杨 杨庆 《岩土力学》 EI CAS CSCD 北大核心 2024年第5期1356-1364,共9页
单点系泊系统因其克服恶劣海况的优越性成为我国海洋石油开发的重要系泊形式。然而,水下单点系泊系统锚桩-土体相互作用机制尚不清楚,尤其缺少考虑系泊点深度的水平承载性能计算方法。基于复合地基反力法,建立水平荷载下单点系泊系统锚... 单点系泊系统因其克服恶劣海况的优越性成为我国海洋石油开发的重要系泊形式。然而,水下单点系泊系统锚桩-土体相互作用机制尚不清楚,尤其缺少考虑系泊点深度的水平承载性能计算方法。基于复合地基反力法,建立水平荷载下单点系泊系统锚桩的挠曲控制方程和边界条件,并编制相关计算程序;通过迭代法求解,获得不同系泊点位置下的锚桩荷载-位移曲线以及桩身位移、弯矩沿桩身的分布规律曲线;通过与数值模拟和既有离心模型试验结果的对比分析,验证了其准确性和可靠性;继而考虑系泊点深度对锚桩水平承载力的影响,进行参数分析,给出了最优系泊点深度取值范围。分析结果表明,增加系泊点深度可以显著减小锚桩的水平位移及弯矩最大值,从而提高锚桩的水平极限承载力。 展开更多
关键词 单点系泊系统 锚桩 水平承载力 理论分析
下载PDF
基于Rayleigh分布扰动状态概念的单桩承载特性研究
20
作者 马彬 殷伟平 张乾青 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第9期76-86,共11页
基于扰动状态概念(Disturbed State Concept,DSC),结合Rayleigh分布从微观角度描述桩-土界面荷载渐进性传递特性,建立了基于DSC理论的桩侧及桩端荷载传递模型,给出了模型参数确定方法,并验证了模型的合理性.同时结合桩侧及桩端荷载传递... 基于扰动状态概念(Disturbed State Concept,DSC),结合Rayleigh分布从微观角度描述桩-土界面荷载渐进性传递特性,建立了基于DSC理论的桩侧及桩端荷载传递模型,给出了模型参数确定方法,并验证了模型的合理性.同时结合桩侧及桩端荷载传递模型,提出了一种分析单桩承载特性的迭代算法并验证其合理性.通过算法计算得到的单桩承载特性与案例实测值有较好的一致性,且可较好地反映侧阻及端阻硬化、软化等特性.变参数分析结果表明,基于DSC理论的桩侧及桩端荷载传递模型对不同土层、不同桩基施工工艺都有好的适用性,可较准确地描述桩-土界面荷载传递特性. 展开更多
关键词 扰动状态概念 单桩 荷载传递模型 承载特性
下载PDF
上一页 1 2 89 下一页 到第
使用帮助 返回顶部