Analysis on the Seismic Response of Hangzhou Metro Tunnel in Soft Soils

2012 ◽  
Vol 446-449 ◽  
pp. 966-969
Author(s):  
Guo Cai Wang ◽  
Jun Yao ◽  
Ling Sha ◽  
Lin Chun Yu ◽  
Xu Wei Zheng
Keyword(s):  
Seismic Response ◽  
Seismic Design ◽  
Soft Soil ◽  
Underground Structure ◽  
Response Analysis ◽  
Response Characteristics ◽  
Finite Element Software ◽  
Calculation Results ◽  
Earthquake Load ◽  
Metro Tunnel

A large number of earthquake disasters indicate that the underground structure, such as metro tunnel, is not safe and reliable as people think, and can also be destroyed and collapsed under dynamic load, e.g. earthquake. Therefore, it is necessary to study the seismic response analysis of underground structure in great detail for underground structure under dynamic loading, especially under the earthquake load. Hence, in view of the soft soil of Hangzhou, the 3D non-linear finite element software ADINA is used to study the seismic response of section tunnel of Hangzhou metro line 1, to summarize the earthquake response characteristics of the subway underground structure, and to provide the calculation results of metro tunnel’s seismic response and the change rule of lining deformation and stress. The conclusions obtained can provide some reference values in the seismic design of metro tunnel in soft soil regions.

Analysis for Seismic Response of Compacted Soil-Cement Pile Composite Foundations

2011 ◽  
Vol 368-373 ◽  
pp. 456-460
Author(s):  
Hong Huan Cui ◽  
Li Qun Zhang ◽  
Hai Long Wang
Keyword(s):  
Seismic Response ◽  
Seismic Design ◽  
Seismic Behavior ◽  
Composite Foundation ◽  
Response Analysis ◽  
Compacted Soil ◽  
Rigid Pile ◽  
Soil Cement ◽  
Earthquake Load ◽  
Rigid Pile Composite Foundation

Compacted soil-cement pile possess the excellences both flexible pile and rigid pile. The composite foundation of compacted soil-cement pile are getting more and more applicable to construction． However, the research on their response under dynamic load, especially under earthquake load，is quite limited．Now the seismic response analysis in time domain is performed with finite element method(ABAQUS).Some parameters influencing the anti-seismic behavior of half-rigid pile composite foundation are studied． Based on these research , some conclusions which may be of some value for anti-seismic design of this type of composite foundations are drawn．

The Influence of Soft Soil on the Analysis of Soil-Pile Dynamic Interaction

2011 ◽  
Vol 52-54 ◽  
pp. 1451-1457
Author(s):  
Xu Dong Cheng ◽  
Jie Li ◽  
Yong Wang
Keyword(s):  
Finite Element ◽  
Seismic Design ◽  
Pile Foundation ◽  
Large Scale ◽  
Soft Soil ◽  
Dynamic Interaction ◽  
Finite Element Software ◽  
Ground Treatment ◽  
Calculation Results ◽  
Different Thickness

In the seismic design of pile foundation, current research mainly adopts the theory of auxiliary experiences engineering design methods. In particular ground, the pile must be specially designed to meet the seismic requirements. In this paper, with large scale finite element software ADINA,a 2-d finite element entity model is established to calculate and analyze the influence of soft soil to the dynamic interaction of soft pile-soil under the earthquake. The maximum displacements and acceleration of the measuring points on the pile are analyzed in different thickness and position of the soft soil. Calculation results show that: Soft soil effect the maximal displacement and acceleration of the measuring points on the pile which changed with the different thickness and positions of the soft soil. It should be noticed in the design of pile foundation and ground treatment.

scholarly journals Probabilistic seismic response analysis of coastal highway bridges under scour and liquefaction conditions: does the hydrodynamic effect matter?

2020 ◽  
Vol 1 (1) ◽  
Author(s):  
Xiaowei Wang ◽  
Yutao Pang ◽  
Aijun Ye
Keyword(s):  
Seismic Response ◽  
Seismic Design ◽  
Highway Bridges ◽  
Element Model ◽  
Response Analysis ◽  
Hydrodynamic Effect ◽  
Strong Earthquakes ◽  
Influence Of Water ◽  
Scour Hazard ◽  
Ground Motion Records

AbstractCoastal highway bridges are usually supported by pile foundations that are submerged in water and embedded into saturated soils. Such sites have been reported susceptible to scour hazard and probably liquefied under strong earthquakes. Existing studies on seismic response analyses of such bridges often ignore the influence of water-induced hydrodynamic effect. This study assesses quantitative impacts of the hydrodynamic effect on seismic responses of coastal highway bridges under scour and liquefaction potential in a probabilistic manner. A coupled soil-bridge finite element model that represents typical coastal highway bridges is excited by two sets of ground motion records that represent two seismic design levels (i.e., low versus high in terms of 10%-50 years versus 2%-50 years). Modeled by the added mass method, the hydrodynamic effect on responses of bridge key components including the bearing deformation, column curvature, and pile curvature is systematically quantified for scenarios with and without liquefaction across different scour depths. It is found that the influence of hydrodynamic effect becomes more noticeable with the increase of scour depths. Nevertheless, it has minor influence on the bearing deformation and column curvature (i.e., percentage changes of the responses are within 5%), regardless of the liquefiable or nonliquefiable scenario under the low or high seismic design level. As for the pile curvature, the hydrodynamic effect under the low seismic design level may remarkably increase the response by as large as 15%–20%, whereas under the high seismic design level, it has ignorable influence on the pile curvature.

Seismic Response Analysis of Soil-Structure Interaction on Base Isolation Structure

2013 ◽  
Vol 663 ◽  
pp. 87-91
Author(s):  
Ying Bo Pang
Keyword(s):  
Finite Element ◽  
Seismic Response ◽  
Soil Structure ◽  
Base Isolation ◽  
Soil Structure Interaction ◽  
Response Analysis ◽  
Analysis Model ◽  
Seismic Response Analysis ◽  
Structure Interaction ◽  
Calculation Results

As an effective way of passive damping, isolation technology has been widely used in all types of building structures. Currently, for its theoretical analysis, it usually follows the rigid foundation assumption and ignores soil-structure interaction, which results in calculation results distortion in conducting seismic response analysis. In this paper, three-dimensional finite element method is used to establish finite element analysis model of large chassis single-tower base isolation structure which considers and do not consider soil-structure interaction. The calculation results show that: after considering soil-structure interaction, the dynamic characteristics of the isolation structure, and seismic response are subject to varying degrees of impact.

Numerical research on seismic response characteristics of shallow buried rectangular underground structure

2019 ◽  
Vol 116 ◽  
pp. 242-252 ◽  
Author(s):  
Zigang Xu ◽  
Xiuli Du ◽  
Chengshun Xu ◽  
Hong Hao ◽  
Kaiming Bi ◽  
...  
Keyword(s):  
Seismic Response ◽  
Underground Structure ◽  
Response Characteristics ◽  
Numerical Research

Study on the Stratum Displacement Changes Caused by the Vertical Shaft Construction in Saturated Ultra Soft Soil

2012 ◽  
Vol 170-173 ◽  
pp. 1005-1012
Author(s):  
Lin You Pan ◽  
Xiao Bing Li ◽  
Chuang Yu ◽  
Fu Xue Sun
Keyword(s):  
Soft Soil ◽  
Field Tests ◽  
Horizontal Displacement ◽  
Vertical Displacement ◽  
Soil Disturbance ◽  
Soil Parameters ◽  
Finite Element Software ◽  
Total Displacement ◽  
Calculation Results ◽  
Engineering Information

In view of Wenzhou saturated super soft soil, This article studied the influence of different soil parameters for the shaft excavation construction and the stratum displacement change law by using Plaxis finite element software, according to the data obtained in field tests. The considered factors included the lateral brace stiffness, the stiffness of the underground diaphragm wall, and the surrounding soil disturbance. The calculation results provided much important engineering information, such as the horizontal displacement nephogram, the vertical displacement nephogram and the total displacement incremental vector diagram of each construction steps, which can be referred for the construction of the similar underground projects in soft soil areas.

Elasto-Plastic Analysis of Seismic Response of Valve-Hall Structure with Suspension Valves of Large-Scale Converter Station

2011 ◽  
Vol 94-96 ◽  
pp. 1941-1945
Author(s):  
Yi Wu ◽  
Chun Yang ◽  
Jian Cai ◽  
Jian Ming Pan
Keyword(s):  
Seismic Response ◽  
Large Scale ◽  
Seismic Waves ◽  
Tensile Force ◽  
Response Analysis ◽  
Vertical Acceleration ◽  
Seismic Responses ◽  
Seismic Response Analysis ◽  
Finite Element Software ◽  
Plastic Analysis

Elasto-plastic analysis of seismic responses of valve hall structures were carried out by using finite element software, and the effect of seismic waves on the seismic responses of the valve hall structures and suspension equipments were studied. Results show that significant torsional responses of the structure can be found under longitudinal and 3D earthquake actions. Under 3D earthquake actions, the seismic responses of the suspension valves are much more significant than those under 1D earthquake actions, the maximum tensile force of the suspenders is about twice of that under 1D action. The seismic responses of the suspension valves under vertical earthquake actions are much stronger than those under horizontal earthquake actions, when suffering strong earthquake actions; the maximum vertical acceleration of the suspension valves is about 4 times of that under horizontal earthquake actions. It is recommended that the effects of 3D earthquake actions on the structure should be considered in seismic response analysis of the valve hall structure.

scholarly journals Seismic Response Analysis and Control of Frame Structures with Soft First Storey under Near-Fault Ground Motions

2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Chunyang Liu ◽  
Peng Sun ◽  
Ruofan Shi
Keyword(s):  
Seismic Response ◽  
Ground Motion ◽  
Seismic Performance ◽  
Frame Structures ◽  
Response Analysis ◽  
Main Structure ◽  
Response Characteristics ◽  
Near Fault ◽  
Buckling Restrained Brace ◽  
Near Fault Ground Motion

This paper proposes two kinds of arrangements of buckling-restrained brace dampers to strengthen soft-first-storey structures locally. Two types of near-fault ground motion, with and without pulse, were selected for a study of the seismic response characteristics of soft-first-storey structures with and without buckling-restrained brace dampers, and the effects of different bracing arrangements on improving the seismic performance of soft-first-storey structures were recognized. The results show that, compared with pulse-free ground motion, near-fault pulsed ground motion results in a more severe seismic response in soft-first-storey frame structures, leading to more serious and rapid destruction of the main structure. Buckling-restrained brace dampers have an obvious energy dissipation effect, play a better role in protecting the main structure, and have good practicality. Compared with structures in which the buckling-restrained brace dampers are arranged only on the bottommost layer, the bottom-four-layer-support structure is more advantageous in terms of seismic performance.

Seismic design spectra for different soil classes

2013 ◽  
Vol 46 (2) ◽  
pp. 79-87 ◽  
Author(s):  
Rajesh P. Dhakal ◽  
Sheng-Lin Lin ◽  
Alexander K. Loye ◽  
Scott J. Evans
Keyword(s):  
Seismic Design ◽  
Soft Soil ◽  
Response Analysis ◽  
Seismic Demand ◽  
Analysis Tool ◽  
Spectral Acceleration ◽  
Acceleration Response ◽  
Design Spectra ◽  
Nonlinear Site Response ◽  
Short Period

This paper investigates the validity of the soil class dependent spectral shape factors used to calculate seismic design actions in the New Zealand seismic design standard NZS1170.5, which currently specifies seismic design spectra corresponding to five different soil classes. According to the current provisions stipulated in NZS1170.5, for all natural periods, the seismic demand for structures on soft soil is either equal to or greater than that for structures on hard soil. This is opposite to the basic structural dynamics theory which suggests that an increase in stiffness of a system results in an increase in the acceleration response. In this pretext, a numerical parametric study is undertaken using a nonlinear site response analysis tool in order to capture the effect of soil characteristics on structural seismic demand and to scrutinize the validity of the current site specific seismic design spectra. It is identified that the level of input ground motion intensity and shear stiffness of the soil deposit (represented by its shear wave velocity Vs) greatly affect the maximum acceleration and frequency content of the surface motion. The study found some shortfalls in the way the current code defines seismic design demand, in particular the hierarchy of soil stiffness at low structural periods. It was found that stiff soils generally tend to have a higher spectral acceleration response in comparison to soft soils although this trend is less prominent for high intensity bed rock motions. It was also found that for medium to hard soils the spectral acceleration response at short period is grossly underestimated by the current NZS1170.5 provisions. Based on the outcomes of the parametric numerical analyses, a revised strategy to determine structural seismic demand for different soil classes is proposed and its application is demonstrated through an example.

Sign in / Sign up

Export Citation Format

Share Document