Shaking Table Test on Dynamic Response of Bedding Rock Slopes With Weak Structural Plane Under Earthquake

Taking a bedding rock slope with weak structural plane as the prototype, a shaking table test with a similarity ratio of 1:10 is designed and carried out. By analyzing the acceleration and displacement responses at different positions of the slope, the seismic response and instability mechanism of rock bedding slope under different seismic amplitudes, frequencies, and durations are studied. Before the failure of the slope, the rock bedding slope shows an obvious “elevation effect” and “surface effect” under the action of Wenchuan Wolong earthquake wave with different amplitudes. With the increase of the amplitude of the input seismic wave, the elevation effect and the surface effect gradually weaken. When the amplitude of the seismic wave reaches 0.9 g, the rock bedding slope begins to show damage, which demonstrates that the difference of PGA amplification coefficients on both sides of the weak structural plane increases significantly. Compared with the Kobe seismic wave and Wenchuan Wolong seismic wave, the excellent frequency of EL Centro seismic wave is closer to the first-order natural frequency of slope model and produces resonance phenomenon, which leads to the elevation effect of PGA amplification coefficient more significantly. Through the analysis of the instability process of rock bedding slope, it can be found that the failure mechanism of the slope can be divided into two stages: the formation of sliding shear plane and the overall instability of the slope.

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Seismic Response of a Bridge Pile Foundation during a Shaking Table Test

Shock and Vibration ◽

10.1155/2019/9726013 ◽

2019 ◽

Vol 2019 ◽

pp. 1-16 ◽

Cited By ~ 1

Author(s):

Yunxiu Dong ◽

Zhongju Feng ◽

Jingbin He ◽

Huiyun Chen ◽

Guan Jiang ◽

...

Keyword(s):

Seismic Wave ◽

Pile Foundation ◽

Large Scale ◽

Amplification Factor ◽

Shaking Table Test ◽

Seismic Intensity ◽

Shaking Table ◽

Acceleration Amplification ◽

Bedrock Surface ◽

Bridge Pile Foundation

Puqian Bridge is located in a quake-prone area in an 8-degree seismic fortification intensity zone, and the design of the peak ground motion is the highest grade worldwide. Nevertheless, the seismic design of the pile foundation has not been evaluated with regard to earthquake damage and the seismic issues of the pile foundation are particularly noticeable. We conducted a large-scale shaking table test (STT) to determine the dynamic characteristic of the bridge pile foundation. An artificial mass model was used to determine the mechanism of the bridge pile-soil interaction, and the peak ground acceleration range of 0.15 g–0.60 g (g is gravity acceleration) was selected as the input seismic intensity. The results indicated that the peak acceleration decreased from the top to the bottom of the bridge pile and the acceleration amplification factor decreased with the increase in seismic intensity. When the seismic intensity is greater than 0.50 g, the acceleration amplification factor at the top of the pile stabilizes at 1.32. The bedrock surface had a relatively small influence on the amplification of the seismic wave, whereas the overburden had a marked influence on the amplification of the seismic wave and filtering effect. Damage to the pile foundation was observed at 0.50 g seismic intensity. When the seismic intensity was greater than 0.50 g, the fundamental frequency of the pile foundation decreased slowly and tended to stabilize at 0.87 Hz. The bending moment was larger at the junction of the pile and cap, the soft-hard soil interface, and the bedrock surface, where cracks easily occurred. These positions should be focused on during the design of pile foundations in meizoseismal areas.

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Shaking Table Tests for Seismic Response of Orthogonal Overlapped Tunnel under Horizontal Seismic Loading

Advances in Civil Engineering ◽

10.1155/2021/6633535 ◽

2021 ◽

Vol 2021 ◽

pp. 1-19

Author(s):

Honggang Wu ◽

Hao Lei ◽

Tianwen Lai

Keyword(s):

Dynamic Response ◽

Seismic Response ◽

Seismic Wave ◽

Shaking Table Test ◽

Shaking Table ◽

Shaking Table Tests ◽

Acceleration Response ◽

Test Device ◽

Deformation Stages ◽

Superposition Effect

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.

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Study on Synthesis Method of Multipoint Seismic Waves for Buried Oil and Gas Pipeline in Shaking Table Tests

Shock and Vibration ◽

10.1155/2021/4624871 ◽

2021 ◽

Vol 2021 ◽

pp. 1-8

Author(s):

Jian-Bo Dai ◽

Gui-Di Zhang ◽

Cheng-Tao Hu ◽

Kai-Kai Cheng

Keyword(s):

Seismic Wave ◽

Seismic Waves ◽

Oil And Gas ◽

Shaking Table Test ◽

Synthesis Method ◽

Linear Structure ◽

Gas Pipeline ◽

Shaking Table ◽

Infinite Length ◽

Shaking Table Tests

The buried oil and gas pipeline is a linear structure with infinite length. In the shaking table test of its seismic response, it is necessary to input the spatially related multipoint seismic wave considering the propagation characteristics of ground motion. The multipoint seismic excitation shaking table tests and loading scheme of buried oil and gas pipelines are designed and formulated. The synthesis method of spatial correlation multipoint seismic wave for the buried oil and gas pipeline test is proposed in this study. The values of relevant parameters are analyzed, and corresponding program is compiled by MATLAB. The results show that the developed multipoint excitation shaking table seismic wave input scheme is reasonable. At the same time, the synthesized multipoint seismic wave based on the actual seismic record and artificial random simulation seismic wave can meet the test requirements, which suggests the testing effect is good.

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Dynamic Failure Mode and Dynamic Response of High Slope Using Shaking Table Test

Shock and Vibration ◽

10.1155/2019/4802740 ◽

2019 ◽

Vol 2019 ◽

pp. 1-19 ◽

Cited By ~ 10

Author(s):

Zhijun Zhou ◽

Chenning Ren ◽

Guanjun Xu ◽

Haochen Zhan ◽

Tong Liu

Keyword(s):

Dynamic Response ◽

Failure Modes ◽

Shaking Table Test ◽

Shaking Table ◽

Amplification Coefficient ◽

Seismic Load ◽

Dynamic Failure ◽

High Slope ◽

Amplification Effect ◽

Slope Line

A shaking table test was performed to study the dynamic response and failure modes of high slope. Test results show that PGA amplification coefficients increased with increasing elevation and the PGA amplification coefficient of the concave slope was slightly larger than that of the convex slope. The slope type affected the dynamic response of the slope. The elevation amplification effect of the concave slope under seismic load was more significant than that of the convex slope; thus, the concave slope was more unstable than the convex slope. Additionally, the PGA amplification coefficient measured on the slope surface was always larger than that inside the slope, and the data show an increasing trend with the broken line. The dynamic amplification effect of the high slope was closely related to the natural frequency of the slope. Within a certain range, the higher the frequency, the more significant the amplification effect. The dynamic failure process of concave and convex slopes was studied through tests. Findings indicate that the dynamic failure modes of the concave slope are characterized by shoulder collapse, formation of the sliding surface, and integral sliding above the slope line. Dynamic failure modes of the convex slope are mainly slips in the soil layer and collapse of the slope near the slope line.

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Acceleration Data Acquisition and Analysis Method of Shaking Table Test

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.724.205 ◽

2015 ◽

Vol 724 ◽

pp. 205-212 ◽

Cited By ~ 1

Author(s):

Shao Feng Chai ◽

Ping Wang ◽

Zhi Jian Wu ◽

Jun Wang ◽

Gao Feng Che

Keyword(s):

Data Processing ◽

Test Data ◽

Shaking Table Test ◽

Damping Ratio ◽

Shaking Table ◽

Amplification Coefficient ◽

Response Analysis ◽

Analysis Method ◽

Stability And Instability ◽

Sine Sweep

Shaking table test is an important means of simulated earthquake in laboratory, slope shaking table test data provide a scientific basis for analysis of dynamic stability and instability mechanism of slopes. Sine vibration table test data processing is different from general frequency domain analysis method, need real-time data processing in time domain. Taking the sine sweep test conditions, which is one of the conditions in "Earthquake landslide and slope prevention and control technology research on shaking table test", as an example. Describes the layout of sensors in shaking table test and the reasons; Sine sweep test load and aim; and listed the steps and methods of the sine sweep test in data processing; Through the processing and analysis of test data identified the vibration frequency of model and shaking table system is 30Hz, damping ratio is 2.06%; Analysis and calculation of the different sections of the slope and position of the amplification coefficient. A methodological guidance for shaking table test and dynamic response analysis of the slope is provided.

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Research on Seismic Dynamic Response Characteristics of Weak Surrounding Rock Slope With Double-Arch Tunnel

10.21203/rs.3.rs-517421/v1 ◽

2021 ◽

Author(s):

Xueliang Jiang ◽

Yonghui Qian ◽

Jiqi Zhang ◽

Yong Liu ◽

RiWe Deng ◽

...

Keyword(s):

Seismic Wave ◽

Amplification Factor ◽

Shaking Table Test ◽

Shaking Table ◽

Dynamic Displacement ◽

Displacement Response ◽

Response Characteristics ◽

Acceleration Amplification ◽

Dynamic Response Characteristics ◽

Peak Value

Abstract Through the shaking table test, Wenchuan wave (WC) was used as the excitation wave of the shaking table test. The vibration was excited in three directions: horizontal (x), vertical (z), and horizontal and vertical (xz) and the dynamic response characteristics of rock slopes was studied. The results show:(1) The acceleration amplification factor of each measuring point of the slope shows a nonlinear increasing trend with the increase of the slope height.The slope changes the frequency spectrum of the loaded seismic wave.The slope has a filtering effect on the high frequency band of the seismic wave.(2) Under the unidirectional cyclic loading of Wenchuan wave, the slope acceleration amplification factor increases with the increase of the peak value of the seismic wave. Under the bi-directional excitation of Wenchuan wave, the slope acceleration amplification coefficient generally decreases with the increase of the peak value of the seismic wave.The slope acceleration amplification factor presents the characteristics of first increasing and then decreasing with the increase of the relative height of the slope.(3) The dynamic displacement response characteristics of the tunnel slope with double-arch tunnel are mainly affected by the seismic wave in the same direction and the peak value of the dynamic displacement response increases with the increase of the seismic wave peak value.(4) The peak dynamic displacement response of the double-arch tunnel slope shows a non-linear change trend with the increase of slope height. The dynamic displacement peak growth rate is slower below the rock interface and the dynamic displacement peak increases rapidly above the interface and Maximum displacement occurred at the top of the slope.

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Response analysis of the nodes of pipe networks under seismic load

PLoS ONE ◽

10.1371/journal.pone.0247677 ◽

2021 ◽

Vol 16 (3) ◽

pp. e0247677

Author(s):

Delong Huang ◽

Aiping Tang ◽

Qiang Liu ◽

Dianrui Mu ◽

Yan Ding

Keyword(s):

Finite Element ◽

Shaking Table Test ◽

Element Model ◽

Relative Displacement ◽

Shaking Table ◽

Amplification Coefficient ◽

System Response ◽

Response Analysis ◽

Seismic Load ◽

Pipe Network

Transient ground displacement (TGD) that is caused by earthquakes can damage underground pipes. This damage is especially critical for the joints, elbows and tees of the pipes which play an important role in the operation of a pipe network. In this study, a scale pipe network with both elbows and tees, as well as some components of the pipe network with only tees or elbows, has been investigated. The response of the nodes of a pipe network, when installed in non-uniform geology, was analyzed using the shaking table test and ABAQUS finite element simulation. This paper has firstly introduced the preparation of the test and the developed finite element model. Then the system response in terms of strain, the friction, the bending deformation, the node deformation amplification coefficient and the pipe-soil relative displacement along the pipe axis of the pipe network and two pipe network components have been analyzed explaining the correlation between these responses. Finally, the influence of elbows and tees on the pipe network was analyzed, and the conclusions that have been reached about how tees and elbows can change the response of a pipe network during an earthquake can provide theoretical support for the seismic design and layout of an underground pipe network.

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Study of Shaking Table Test on Seismic Performance of 750 kV Post Insulator

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1065-1069.1491 ◽

2014 ◽

Vol 1065-1069 ◽

pp. 1491-1496

Author(s):

Sen Lin ◽

Zhi Cheng Lu ◽

Zhu Bing Zhu ◽

Po Gao ◽

Sheng Li

Keyword(s):

Seismic Performance ◽

Seismic Wave ◽

Seismic Waves ◽

Shaking Table Test ◽

Seismic Analysis ◽

Performance Estimation ◽

Shaking Table ◽

Wave Condition ◽

Standard Wave ◽

Post Insulator

The applicability of seismic waves for the seismic performance estimation of 750 kV post insulator has been investigated in full-scale shaking table test. the input seismic waves comprise El Centro seismic wave, Landers seismic wave, sine beat wave and artificial standard wave. The testing results indicate that, high dynamic responses of the equipment can be obtained under artificial standard wave condition. In addition, due to comprehensive enveloping ability and gentle spectral curve, artificial standard wave is ideal for the seismic performance evaluation of 750 kV post insulator in the test. An finite element model has been developed and numerical seismic analysis has been performed. Satisfactory match between the simulated and measured results reveals the reliability of the test. The achievements obtained in this paper are helpful in choosing reasonable input wave for shaking table test, and also provide technical support on determining seismic capacity of high voltage electrical equipment.

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Shaking table test of acceleration response of surrounding rock of the 3D cross tunnel under earthquake

Journal of Vibration and Control ◽

10.1177/10775463211039901 ◽

2021 ◽

pp. 107754632110399

Author(s):

Lifang Pai ◽

Honggang Wu ◽

Hao Lei

Keyword(s):

Wave Propagation ◽

Seismic Wave ◽

Seismic Design ◽

Shaking Table Test ◽

Seismic Wave Propagation ◽

Surrounding Rock ◽

Shaking Table ◽

Peak Ground Velocity ◽

Acceleration Response ◽

Ground Acceleration

Taking the 3D cross-engineering of Caomeigou No.1 Tunnel and Pandaoling Tunnel as an example, a shaking table test was carried out to study the effect of tunnel spatial position on seismic wave propagation characteristics and acceleration response of surrounding rock under earthquake seismic excitation. Based on the influence of the spatial position of the tunnel, the characteristic form of the surrounding rock between the cross section and non-cross section is divided, and the accelerometer layout scheme is designed. Based on statistical probability, the ratio of peak ground velocity to peak ground acceleration (PGA) was introduced to quantitatively characterize the characteristics of seismic wave propagation spectrum. Furthermore, the SPECTR calculation was used to obtain the regional difference in the seismic wave propagation potential damage potential displacement parameter ( P d). Under the influence of the spatial location of the 3D cross tunnel, the peak acceleration and motion duration of the seismic wave are mainly reflected in the variation of the section along the elevation direction. Low-frequency (≤20 Hz) seismic waves have a greater impact on the tunnel structure, and peak ground velocity/peak ground acceleration ratio has a positive correlation with the peak input energy of ground motion. The ultra-small net-spacing cross tunnel has a spatially distributed coupling deformation effect. The crown of the upper-span tunnel is highly sensitive to earthquakes and becomes a weak link in seismic design. These results help us provide a theoretical basis for the seismic design of the cross-tunnel.

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Study on Damage Evolution Mechanism of Rock-Soil Mass of Accumulation Slope Based on Shaking Table Test

10.21203/rs.3.rs-644142/v1 ◽

2021 ◽

Author(s):

Changwei Yang ◽

Xinhao Tong ◽

Zhifang Zhang ◽

Sujian Ma ◽

Liang Zhang ◽

...

Keyword(s):

Transfer Function ◽

Frequency Response ◽

Modal Analysis ◽

Response Function ◽

Seismic Wave ◽

Frequency Response Function ◽

Shaking Table Test ◽

Shaking Table ◽

Transfer Function Analysis ◽

Accumulation Slope

Abstract To investigate the seismic dynamic characteristics of the accumulation slope, a slope of the Zheduo Mountain tunnel along the Sichuan-Tibet Railway in China was selected as the prototype, based on dimensional analysis and similarity principle, two groups of model tests were carried out at 50° accumulation slope and 60° accumulation slope to obtain the dynamic response influenced by different amplitude of seismic wave. A transfer function analysis method suitable for shaking table test is proposed. Based on the data pretreatment method of eliminating trend terms and digital filter, the frequency response function was calculated by method of average periodic chart. And the variation of frequency response function was analyzed by Pearson correlation coefficient. At last, the least square iteration method was used for modal analysis. It is found that the transfer function changes obviously when both the slopes are destroyed, the weak interlayer has a significant influence on seismic wave transmission. The modal analysis results show that with the increase of the excitation intensity, the natural frequency decreases and the damping ratio increases.

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