Study on dynamic response of embedded long span corrugated steel culverts using scaled model shaking table tests and numerical analyses

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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Full-Model Shaking Table Tests of Seismic Behavior of a Super-Long-Span Cable-Stayed Bridge with Pile Foundations

Journal of Bridge Engineering ◽

10.1061/(asce)be.1943-5592.0001478 ◽

2019 ◽

Vol 24 (11) ◽

pp. 04019102 ◽

Cited By ~ 6

Author(s):

Limin Sun ◽

Wen Xie

Keyword(s):

Seismic Behavior ◽

Shaking Table ◽

Pile Foundations ◽

Full Model ◽

Shaking Table Tests ◽

Cable Stayed Bridge ◽

Long Span

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Shaking Table Tests on Earthquake Response Characterization of a Complex Museum Isolated Structure in High Intensity Area

Shock and Vibration ◽

10.1155/2016/7974090 ◽

2016 ◽

Vol 2016 ◽

pp. 1-23 ◽

Cited By ~ 20

Author(s):

Wenguang Liu ◽

Chuan Qin ◽

Yang Liu ◽

Wenfu He ◽

Qiaorong Yang

Keyword(s):

Structural Model ◽

Base Isolation ◽

Shaking Table ◽

Isolation Effect ◽

Structural Safety ◽

Functional Requirements ◽

Shaking Table Tests ◽

Earthquake Intensity ◽

Long Span ◽

Museum Design

Owing to special functional requirements of museum, such as great space and story height for exhibitions, large floor slab openings in plan and long span truss in elevation are becoming increasingly considered in museum design, which leads to challenges to structural safety. The aseismic performance of an isolated museum structure in high earthquake intensity regions was thus studied because of its complexity and irregularity. In order to observe the seismic characteristics and verify isolation effect, shaking table tests of a 1/30-scale structural model with and without base isolation bearings have been carried out under minor, moderate, and major earthquakes. The experimental results show that isolated structure dynamic characteristics and isolation effect are stable and storey peak acceleration responses of superstructure are less than that of fixed structure. Storey drifts of isolated structure meet required limits stipulated in Chinese design code and torsion responses of the bearings are not remarkable. It is suggested that seismic performances of complex museum structures have been effectively improved with isolation in use.

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Investigations on the Seismic Responses of Structures with a Suspended Mass

International Journal of Structural Stability and Dynamics ◽

10.1142/s0219455415500662 ◽

2016 ◽

Vol 16 (02) ◽

pp. 1550066

Author(s):

Wenhui Wei ◽

Aoxiong Dai ◽

Yong-Lin Pi ◽

Mark Andrew Bradford

Keyword(s):

Seismic Response ◽

Ground Motion ◽

Power Transmission ◽

Ground Motions ◽

Equations Of Motion ◽

Shaking Table ◽

Shaking Table Tests ◽

Scaled Model ◽

High Voltage Direct Current ◽

Horizontal Ground Motion

This paper presents the shaking table tests and an analytical study of structures with a suspended mass under coupled horizontal and tilting ground motions (CHT) caused by an earthquake. Shaking table tests of a 1:10 scaled model for a converter valve hall with a suspended mass in a high-voltage direct current electric power transmission station are carried out. The equations of motion for the structure, including the influence of the rotary inertia of the suspended mass, are derived. The responses of the model to different ground motions during an earthquake are investigated. It is found that the tilting ground motion plays a significant role in predicting the seismic response of the structure, and it needs to be considered in association with the horizontal ground motion. The response of the structure with a suspended mass to CHT ground motion is much larger than that to horizontal ground motion. The possibility of replacing the steel cables with springs as the suspending components is also investigated, and the spring is shown not to influence the acceleration and displacement responses greatly, but it significantly reduces the tension in the suspending components. Therefore, when a suspended mass is used as a mass-pendulum mitigation system, it is more advantageous to use springs or members having a low axial rigidity as the suspending components. In addition, the effects of the length of the cables and springs on the seismic response of the model with a suspended mass are also explored. It is found that the shorter the cables (or springs), the better the mitigation effects of the suspended mass on the main structure.

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