Shaking Table Test of Underground Pipeline under Three Dimension Seismic Excitation – Numerical Simulation

2014 ◽  
Vol 919-921 ◽  
pp. 960-964 ◽  
Author(s):  
Xiao Fu ◽  
Jun Wei Bi ◽  
Zhi Jia Wang ◽  
Chang Wei Yang

Based on the design of the large-scale shaking table test of an underground pipeline under three dimension seismic excitation, the dynamic response of the soil-structure is analyzed by using ANSYS. In the numerical simulation, Drucker-Prager constitutive model is adopted to simulate the soil, the interface between soil and pipeline are simulated with zero thickness contact elements, size effects of test box are diminished by defining viscoelastic boundary around soil, the acceleration time history curve of the original earthquake wave is compressed and processed according to using the model scale similarity and energy duration which is presented by Trifunac-Brady [1] , and then the characteristic of seismic response of the pipeline can be found. The results show that the top of pipeline is the seismic response intense regional, deformation displacements of the central areas at the bottom and top of pipeline are always larger than others, the entrance and exit are the weak positions of anti-seismic structure; moreover, the dynamic response and interactions of soil-pipeline in the model experiment can be more accurately simulated by the methods presented in the paper. Thus, it can be served as reference for the design and construction of subsurface structures.

2010 ◽  
Vol 163-167 ◽  
pp. 165-168
Author(s):  
Ruo Qiang Feng ◽  
Ji Hong Ye ◽  
Yue Wu ◽  
Shi Zhao Shen

Shaking table tests and theoretical analysis were conducted to study of the seismic response of cable net facade. Firstly dynamic response of cable net façade under earthquake was investigated with shaking table test. Then a numerical simulation model of cable net façade was built for the dynamic analysis .And then with this model the seismic response was analyzed theoretically. The study indicates that: the seismic response of the cable net with glass panels and the cable net on most occasions are mainly decided by the symmetric modes, and the first vibration mode is dominant. The damping of cable net facade is mainly decided by glass panels.


2021 ◽  
Vol 2021 ◽  
pp. 1-19
Author(s):  
Honggang Wu ◽  
Hao Lei ◽  
Tianwen Lai

This paper presents the seismic dynamic response and spectrum characteristics of an orthogonal overlapped tunnel by shaking table tests. First, a prototype of the engineering and shaking table test device, which was used to design details of the experiment, was developed. Then, the sensors used in the test were selected, and the measurement points were arranged. Subsequently, the Wenchuan seismic wave with horizontal direction in different peak ground accelerations was inputted into the model, followed by a short analysis of the seismic response of the overlapped tunnel in the shaking table test as well as the distribution of the peak acceleration. Throughout the studies, the model exhibited obvious deformation stages during the seismic wave loading process, which can be divided into elastic, plastic, plastic enhancement, and failure stage. In particular, the time- and frequency-domain characteristics of the key parts of the tunnel were discussed in detail by using the continuous wavelet transform (CWT) based on the Morlet wavelet as the basis function. We found that the acceleration response was more intense within 25–60 s after the seismic wave was inputted. Furthermore, owing to “the superposition effect,” the seismic response at the crown of the under-crossing tunnel was stronger than that at the invert of the upper-span tunnel. The low and medium frequencies in the transformation of small scales (5–20) significantly affected the overlapped tunnel. These results elucidate the seismic dynamic response of the overlapped tunnel and provide guidance for the design of stabilizing structures for reinforcing tunnels against earthquakes.


2021 ◽  
Vol 2 (2) ◽  
Author(s):  
Kan Han ◽  
Chunxiao Xue

In order to reduce the damage of liquefaction of aeolian sand along the Sichuan-Tibet railway, the dynamic response characteristics of saturated aeolian sand in the study area were discussed by using shaking table test. The results show that the macroscopic characteristics of saturated aeolian sand in the study area are subsidence, water flow and fracture. The displacement time history shows that the surface displacement increases with increasing the input ground motion acceleration. When the acceleration is small (0.1g), the vibration in the soil layer has an obvious tendency to enlarge continuously from bottom to top. With the increase of the acceleration (0.2g), the amplification trend basically disappeared. When the acceleration increases to 0.3g, the ground motion increases first and then decreases.


2018 ◽  
Vol 2018 ◽  
pp. 1-14
Author(s):  
Xuelei Cheng ◽  
Chunyi Cui ◽  
Zongguang Sun ◽  
Jinhong Xia ◽  
Guangbing Wang

This paper investigates shaking table test (1g) and numerical simulation (fully coupled) of vertically propagating shear waves for saturated soft free field. A large-scale shaking table model test was performed to study seismic response characteristics of saturated soft soil free field. According to test results of seismic response features of free field system in saturated soft soil, the free field nonlinearity fully coupled numerical model of dynamical effective stress of saturated soft soil was established using OpenSEES, based on the u-p formulations of dynamic consolidation equation as well as effective stress solution method for saturated two-phase media. The numerical simulation of the free field seismic response of saturated soft soil under various test conditions was performed and the calculated results were compared with the shaking table test results. The results show the following. (1) With the increase of input ground motion intensity, the characteristic frequency of the saturated soft free ground decreases and the damping ratio increases gradually. (2) The saturated soft soil ground has short period filtering and long period amplification effect on the horizontal input seismic loads. The failure foundation takes on the isolation and shock absorption under strong ground motions. (3) The peak pore pressure ratio of the saturated soft soil ground is located in the shallow buried soil layer, and with the increase of the input ground motion intensity, the advantage of dynamic pore pressure ratio in this area is gradually weakened. (4) The numerical simulation results are consistent with the results of the shaking table test. This fully coupled effective stress numerical method can reasonably simulate the seismic response characteristics of free field in saturated soft soil, which lay the foundation for other more complex parameter extrapolation models of saturated soft soil sites. This research can provide the necessary technical experience for experimental study on non-free field.


Symmetry ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 2062
Author(s):  
Zhenwei Lin ◽  
Chao Zhang ◽  
Jucan Dong ◽  
Jianliang Ou ◽  
Li Yu

The interaction between multiple loops and string cables complicates the dynamic response of triple square loops-string dome structures under seismic excitation. The internal connection between the multiple square loops-string cables and the grid beams was studies to provide a favorable reference for an anti-seismic structure. With a finite element model of the Fuzhou Strait Olympic Sports Center Gymnasium, established by SAP2000 software, the structural dynamic characteristic parameters were obtained first, and then this study adopted a time-history analysis method to study the internal force response of the cables and the roof grid beams of the multiple square loops-string dome (MSLSD) under three types of seismic array excitation. The influence of two factors, namely the seismic pulse and the near and far seismic fields, on the dynamic response of this structure was analyzed by three groups of different types of seismic excitation (PNF, NNF, PFF). As shown from the results, the first three-order vibration modes were torsional deformations caused by cables, the last five were mainly the overall roof plane vibration and antisymmetric vibration. Under the excitation of the three seismic arrays, the internal force responses of stay cables, square cables in the outer ring and the string cables were largest, while the maximum internal force response of the struts changed with the direction of seismic excitation. The largest internal force response of the roof grid beams occurred in local components such as BX3, BX7 and BY7, and the largest deformation of the beam nodes occurred in JX7, JX12 and JY4. In general, the seismic pulse and the near seismic field weakened the internal force response of the struts and cables but increased the internal force response and deformation of the dome beams, while the near and far seismic fields outweighed the seismic pulse. All the above provides an important reference for structural monitoring and seismic resistance.


Author(s):  
Teruyoshi Otoyo ◽  
Akihito Otani

This paper shows a benchmark result regarding elastic-plastic seismic response analysis and fatigue evaluation for of piping model excitation test. National Research Institute for Earth Science and Disaster Prevention (NIED) has a lot of experimental results of shaking table test of piping. To propose advance seismic evaluation method for piping under severe seismic event, a task in JSME Code committee performs benchmark activity for elastic plastic seismic response analysis and evaluation for piping by using NIED’s experimental results [1]. Authors are taking part in the task and have been performed a benchmark of seismic response analysis and seismic evaluation by comparing with the experimental results. For fatigue evaluation, the strain ranges and the cycles of each range obtained from strain time history were evaluated. The response acceleration and displacement was evaluated for plastic collapse.


2014 ◽  
Vol 1065-1069 ◽  
pp. 1035-1041
Author(s):  
Si Tian Chen ◽  
Jie Xu ◽  
Hong Hui Xie

This paper is a seismic response study on a vertical irregular frame structure which has a cantilevered top floor. Aimed to analyze the features of seismic response for a vertical irregular frame and scaled model, dynamic time history analysis and shaking table test have been carried out by use of the earthquake waves recorded in WENHUAN earthquake. It shows that the results of dynamic time history analysis and shaking table test are in good agreement, and the earthquake influence coefficients obtained by dynamic time history analysis and shaking table test are larger than the value according to Code, which indicates that the results would be not secure if the simplified methods specified in Code only in the sight of the calculation of earthquake loads.


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