检索结果-南通市图书馆

Numerical Analysis of Interaction Between Pile-Supported Pier and Bank Slope

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

China Ocean engineering 2001年第1期16卷 117-128页

作者： WANG Nianxiang(王年香) geotechnical engineering Department Nanjing Hydraulic Research Institute Nanjing 210024 China

Two and three-dimensional finite element analysis programs for pile-soil interaction are compiled. Duncan-Chang's Model is used. The construction sequence of the pier is modeled. The pile-soil interface element is used. The influence of the combination type of piles on the deformation of bank slope and pile behaviour is analyzed. Different designs of a pile-supported pier are compared thoroughly. Calculation results show that the stresses and displacements of the pile are directly related to the distance from the bank slope and the direction of inclination. An inclined prop pile set in the rear platform would remarkably reduce the stresses of piles and the displacement of the pier.

关键词： interaction pile-supported pier bank slope numerical analysis

Probabilistic analysis of geomembrane puncture from granular material under liquid pressure

在线全文

学校读者我要写书评

暂无评论

Journal of Central South University 2013年第11期20卷 3256-3264页

作者：姜晓桢束一鸣朱俊高 College of Water Conservancy and Hydropower engineering Hohai University Department of geotechnical engineering Nanjing Hydraulic Research Institute institute of geotechnical engineering Hohai University

A simplified probabilistic analysis of geomembrane punctures from granular material was presented when subjected to liquid *** probability distribution of contact force between geomembrane and granular material was obtained based on the principle of equal probability and assumptions that grains are spheres with constant size.A particle flow code PFC3Dwas employed to simulate the contact process which indicates a good agreement with the theoretical probabilistic *** odds of geomembrane puncture from grains of constant size were obtained by evaluating the puncture force which should not exceed the puncture resistance of *** effects of grain radius,grain rigidity and liquid pressure were studied in more detail and displayed in *** high-level of liquid pressure and large grain can result in high risk of geomembrane *** influence of grain rigidity on the geomembrane puncture odds is *** granular material with a grain size distribution,the geomembrane puncture odds can be estimated by the grain size distribution,served as weight function and it is a cautious design if the largest grain is chosen as the design grain size.

关键词： geomembrane puncture probability distribution contact force

Experimental Study on Superficial Sliding of a New Type of Offshore Platform

在线全文

学校读者我要写书评

暂无评论

China Ocean engineering 1996年第1期11卷 121-128页

作者： Wang Zhaojing Zhang Ling Senior Engineer, geotechnical engineering Department, Nanjing hydraulic research institute, Nanjing 210024 Engineer, geotechnical engineering Department, Nanjing hydraulic research institute, Nanjing 210024 geotechnical engineering Department Nanjing Hydraulic Research Institute Nanjing 210024

In order to verify the theoretical design and computation of a new type of platform, laboratory model test of the superficial sliding of the platform is carried out. Test results show that the requirement for the stability of the platform can be satisfied, and the API-82 criterion can be met. It is also suggested that, in order to enhance the stability of the platform, a buried- pad with porous holes and a long apron-board should be adopted in the design of the new type of platform.

关键词： superficial sliding model test offshore platform

An analytical solution to the scattering of cylindrical SH waves by a partially filled semi-circular alluvial valley: near-source site effects

在线全文

学校读者我要写书评

暂无评论

Earthquake engineering and engineering Vibration 2015年第2期14卷 189-201页

作者： Zhang Ning Gao Yufeng Yang Jie Xu Changjie geotechnical research institute Hohai University Key Laboratory of Ministry of Education for Geomechanics and Embankment engineering Hohai University Nanjing hydraulic research institute research Center of Coastal and Urban geotechnical engineering Zhejiang University

The earth’s surface irregularities can substantially affect seismic waves and induce amplifi cations of ground motions. This study investigates whether and how the source characteristics affect the site amplifi cation effects. An analytical model of a line source of cylindrical waves impinging on an alluvial valley is proposed to link the source and site. The analytical solution to this problem proves one aspect of the strong effect of source on site amplifi cation, i.e., the wave curvature effect. It is found that the site amplifi cation depends on the source location, especially under conditions of a small source-to-site distance. Whether the displacement is amplifi ed or reduced and the size of the amplifi cation or reduction may be determined by the location of the source. It is suggested that traditional studies of site responses, which usually ignore the source effect, should be further improved by combining the source with site effects.

关键词： site effects source effects wave function expansio

Probabilistic analysis of random contact force between geomembrane and granular material

在线全文

学校读者我要写书评

暂无评论

Journal of Central South University 2014年第8期21卷 3309-3315页

作者：姜晓桢束一鸣 College of Water Conservancy and Hydropower engineering Hohai University Department of geotechnical engineering Nanjing Hydraulic Research institute

A probabilistic method based on principle of maximum entropy was employed to analyze the randomness of contact force between geomembrane and granular *** contact force distribution is exponential according to the proposed method and the grain size is the most important factor that affects the distribution of contact *** proposed method is then verified by a series of laboratory experiments using glass beads and cobbles as granular material and a very thin pressure,indicating that film is firstly used in these experiments which give a reliable method to measure the contact force at each contact point.

关键词： geomembrane granular material contact force probability density function

Theoretical study on damage bifurcation of unstable failure process of quasi-brittle materials

在线全文

学校读者我要写书评

暂无评论

中国有色金属学会会刊：英文版 2009年第S3期19卷 811-818页

作者：王忠昶赵德深杨庆 Key Laboratory for Prediction&Controlon Complicated structure System of Education Department of Liaoning Province Dalian University institute of geotechnical engineering School of Civil and Hydraulic EngineeringDalian University of Technology

To obtain the damage effect in the process of elasto-plasticity deformation of quasi-brittle materials, the isotropic damage loading-unloading function and damage variable were introduced to non-continuous bifurcation. The critical bifurcation orientation and its corresponding hardening modulus for quasi-brittle materials were derived considering the effect of stiffness degradation and volumetric dilatancy under the assumption of isotropic damage. The relationships of localized orientation angle and maximal hardening modulus dependent on degree of damage and initial Poisson's ratio of rock were explored. Comparative analyses were conducted to study the bifurcation of uniaxial tension-compression samples under the conditions of plane stress and plane strain. It is shown that as the initial Poisson's ratio or degree of damage increases, the localization orientation angle of the plane uniaxial compression sample tends to be initiated to decrease. However, the localization orientation angle of the plane uniaxial tension sample tends to be initiated to increase. The sum of orientation angle under tension and compression conditions is 90°. There are plane stress and plane strain cases of the maximum hardening modulus that is independent of the uniaxial compression and tension.

关键词： isotropic damage orientation of localization maximum hardening modulus bifurcation uniaxial sample

Laboratory-scale investigation of the material distribution characteristics of landslide dams in U-shaped valleys

在线全文

学校读者我要写书评

暂无评论

Journal of Mountain Science 2023年第3期20卷 688-704页

作者： JIAN Fu-xian CAI Zheng-yin GUO Wan-li geotechnical engineering Department Nanjing Hydraulic Research InstituteNanjing 210024China State Key Laboratory of Hydrology-Water Resources and hydraulic engineering Nanjing 210024China

Material distribution characteristics during sliding and depositing is particularly significative to investigate the internal structure and spatial variation of landslide dams,which are fundamentally determining the mechanical and hydraulic behavior and the susceptibility to cause dam ***,limited by longevity shortages and special geographic environments,the material distribution characteristics and their formation mechanisms are difficult to observe in the ***,an experimental apparatus modeling a landslide dam was developed in this paper,designing three sampling methods with two valley *** internal deposit characteristics,void ratio variation and relative content of the particle size range(PSR)were analyzed,and the mechanics of deposit structure were also delicately *** results indicate that granular material deposited in valley shows a structure of inverse grain size accumulation in both vertical and horizontal directions,exhibiting spatial variability of particle gradation and void *** characteristic PSR decreases from 22-30 mm in the two-dimensional state to 10-14 mm in the threedimensional *** excitation and vibration sieve are the intrinsic mechanisms of granular flow segregation,intrinsically inducing the formation of inverse grading deposit ***,spatial variability in size is mainly trig gered by segregation,whereas coarse particle content and deposition boundaries merely exacerbate the difference degree.

关键词： Landslide dam IInverse grading structure Granular flow segregation Material spatial variability Deposit characteristics

Prototype observation and influencing factors of environmental vibrationinduced by flood discharge

在线全文

学校读者我要写书评

暂无评论

Water Science and engineering 2017年第1期10卷 78-85页

作者： Xin Wang Ya-an Hu Shao-ze Luo Lu-chen Zhang Bo Wu hydraulic engineering Department Nanjing Hydraulic Research InstituteNanjing 210029China State Key Laboratory of Hydrology-Water Resources and hydraulic engineering Nanjing Hydraulic Research InstituteNanjing 210029China Key Laboratory of Navigation structure Construction Technology of Ministry of Transport Nanjing Hydraulic Research InstituteNanjing 210029China

Due to a wide range of field vibration problems caused by flood discharge at the Xiangjiaba Hydropower Station, vibration characteristics and influencing factors were investigated based on prototype observation. The results indicate that field vibrations caused by flood discharge have distinctive characteristics of constancy, low frequency, small amplitude, and randomness with impact, which significantly differ from the common high-frequency vibration characteristics. Field vibrations have a main frequency of about 0.5-3.0 Hz and the characteristics of long propagation distance and large-scale impact. The vibration of a stilling basin slab runs mainly in the vertical direction. The vibration response of the guide wall perpendicular to the flow is significantly stronger than it is in other directions and decreases linearly downstream along the guide wall. The vibration response of the underground turbine floor is mainly caused by the load of unit operation. Urban environmental vibration has particular distribution characteristics and change patterns, and is greatly affected by discharge, scheduling modes, and geological conditions. Along with the increase of the height of residential buildings, vibration responses show a significant amplification effect. The horizontal and vertical vibrations of the 7th floor are, respectively, about 6 times and 1.5 times stronger than the corresponding vibrations of the 1st floor. The vibration of a large-scale chemical plant presents the combined action of flood discharge and working machines. Meanwhile, it is very difficult to reduce the low-frequency environmental vibrations. Optimization of the discharge scheduling mode is one of the effective measures of reducing the flow impact loads at present. Choosing reasonable dam sites is crucial.

关键词： Flood discharge Environmental vibration Vibration characteristics Influencing factor Prototype observation

A generalized plasticity model for the stress-strain and creep behavior of rockfill materials

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2019年第4期62卷 649-664页

作者： FU ZhongZhi CHEN ShengShui WEI KuangMin geotechnical engineering Department Nanjing Hydraulic Research Institute Key Laboratory of Failure Mechanism and Safety Control Techniques of Earth-rock Dam

The generalized plasticity constitutive equations that simulate, in a unified manner, the stress-strain response and the creep behavior of rockfill materials are derived using the concept of elastoplasticity. A single yield surface is assumed to capture the onset of plastic strains with, however, two separate potential functions for the stress-induced plastic strains and the creep strains,respectively. The involved tensors and scalars are then specified directly, following the generalized plasticity method, to substantiate the constitutive equations. The model thus obtained is verified using triaxial compression experiments, true triaxial experiments and triaxial creep experiments. The effectiveness of the model is also demonstrated by a successful application in studying the behavior of a high concrete face rockfill dam(CFRD). It is found that for a high CFRD with a long construction period, neglecting the creep of rockfill materials during construction results in an underestimation of the deformation of the *** deformation and stress of the concrete slabs may also be considerably underestimated.

关键词： rockfill materials creep behavior constitutive model generalized plasticity concrete face rockfill dam(CFRD)