Shaking Table Test to Underground Structures in Layered Foundation

2013 ◽  
Vol 353-356 ◽  
pp. 1461-1465
Author(s):  
Wei Feng Sun ◽  
Li Ping Jing ◽  
Yan Zou ◽  
Ning Bo Yang ◽  
Yong Qiang Li

A three-story underground structure shaking table test had been carried on to study the earthquake damage mechanism of underground structure in layered foundation. The test model was similar to typical subway station according to a certain similarity ratio, and the soils were disturbed sandy soil and silty clay dug from the site of Harbin subway. Shaking table tests to this typical model in silty clay and alternating layers of clay and sand were performed to reveal the effect of different layered soils. Results show that the sandy soil layer can reduce the damage of the soil and underground structure, the damage of underground structure is mainly controlled by displacement of the surrounding soil, and the response of shallow buried underground structure is larger than deep buried.

2019 ◽  
Vol 13 (02) ◽  
pp. 1950009 ◽  
Author(s):  
Cuizhou Yue ◽  
Yonglai Zheng ◽  
Shuxin Deng

Central columns have long been demonstrated to play a vital role in withstanding not only static gravity loads but also seismic loads like earthquakes. A series of modeling tests are implemented on shaking table instrument to reflect the mechanism of soil — structure interaction and examine the validity of method of uplifting underground structural seismic resistance through strengthening central columns. An innovative method of enhancing central columns by adhering carbon fiber cloth onto column’s peripheral surface is introduced into a series of shaking table modeling tests, in which two two-layer underground model structures are constructed for comparison, one without any column remedy acts as a benchmark for reference and the other is amended with carbon fiber cloth adhered on column surface. Test results show that soft round model box adopted in tests serves well in simulating earthquake actions with negligible boundary effects on wave transfer; soil dynamic characteristics and the relative stiffness of structure to surrounding soil will interactively limit mutual motion and deformation. Racking deformation assumption may be not applicable for overall two-layer underground structure deformation analysis, but may be suitable for inter-layer displacement calculation for single layer in multi-layer rectangular underground structures. The adopted column enhancement measure could not only greatly increase the stiffness ratio of model structure to soil, reducing structure deformation, but also improve the integrity of underground structure by narrowing down the deformation difference between two structural layers, certifying that such a measure could be validly used in improving the seismic resistance capacity for already built underground structures without enough aseismic consideration when designed.


Author(s):  
Jie Xiong

Since the responses of Liquid storage tanks (LST) include the liquid motion, structural motion, and fluid-structure interaction (FSI) under the earthquake ground motion, it is a difficult problem about shaking table test model for satisfying similarity ratio requirement. The two experimental models, namely satisfied FSI similarity ratio model (FSI model) and unsatisfied FSI similarity ratio (un-FSI) model, respectively, are presented in this paper. The PCS storage tank of AP1000 Nuclear Power Engineering, as the study project, is studied by Adina software, and the responses, such as stress, stain, and displacement, etc., of prototype model, FSI model, and un-FSI model are compared. The results provide that when researchers study the rigidity LST dynamic response parameters and vibration characteristics, such as displacement, acceleration and liquid wave height, the tank wall stress response parameters etc., FSI model should be used.


2021 ◽  
Vol 11 (23) ◽  
pp. 11245
Author(s):  
Ruijie Zhang ◽  
Dan Ye ◽  
Jianting Zhou ◽  
Dengzhou Quan

At present, the seismic design research of underground structures in loess areas is lagging behind compared with practical engineering requirements. The selection of seismic calculation methods and parameters does not consider the influences of the special geological conditions in various regions, so their usefulness is limited. Based on the above problems, a modified displacement-based method (DBM) was proposed and its application was compared with the most commonly used methods of analysis (force-based design method, displacement-based design method, detailed equivalent static analysis numerical method, and the full dynamic time-history method). The results were also validated by considering data from shaking table tests conducted on a case study involving the underground Feitian Road subway station in Xi’an. The results show that compared with DBM, the average accuracy of the modified DBM technique is improved by 41.65%. The modified DBM offers good accuracy, simplicity in its model, a rapid analysis time, and easy convergence.


2020 ◽  
Vol 2020 ◽  
pp. 1-14
Author(s):  
Kunpeng Xu ◽  
Liping Jing ◽  
Xinjun Cheng ◽  
Haian Liang ◽  
Jia Bin

Subgrade reaction coefficient is commonly considered as the primary challenge in simplified seismic design of underground structures. Carrying out test is the most reliable way to acquire this intrinsic soil property. Owing to the limitations of experimental cost, time consumption, soil deformation mode, size effect, and confined condition, the existing testing methods cannot satisfy the requirements of high-precision subgrade reaction coefficient in seismic design process of underground structures. Accordingly, the present study makes an attempt to provide new laboratory testing methods considering realistic seismic response of soil, based on shaking table test and quasistatic test. Conventional shaking table test for sandy free-field was performed, with the results indicating that the equivalent normal subgrade reaction coefficients derived from the experimental hysteretic curves are reasonable and verifying the deformation mode under seismic excitation. A novel multifunctional quasistatic pushover device was invented, which can simulate the most unfavorable deformation mode of soil during the earthquake. In addition, the first successful application of an innovative quasistatic testing method in evaluating subgrade reaction coefficient was reported. The findings of this study provide preliminary detailed insights into subgrade reaction coefficient evaluation which can benefit seismic design of underground structures.


2012 ◽  
Vol 588-589 ◽  
pp. 1889-1893
Author(s):  
Hai Feng Sun ◽  
Li Ping Jing ◽  
Qing Hai Wei ◽  
Xian Chun Meng

Shaking table test is an important method to study on the problem of the soil-structure dynamic interaction. The property of the soil container directly affects the accuracy of the result. A laminar shear container was designed for shaking table test. And a shaking table test on soil-underground structure dynamic interaction which structure lay in clay was conducted. The results of the test show that the container eliminated the boundary effect when the dynamic load was applied in only one horizontal direction. Meanwhile, the stiffness of the soil container could be changed according to the change of the model soil, which is applicable to decrease the boundary effect.


2018 ◽  
Vol 2018 ◽  
pp. 1-19 ◽  
Author(s):  
Ling-Yun Peng ◽  
Ying-Jie Kang ◽  
Zong-Rui Lai ◽  
Yu-Ke Deng

A parameter optimization design method is proposed for multiple coal bucket dampers (CBDs) to reduce the seismic response of coal-fired power plants. To test the damping effect of the optimized CBDs, a 1 : 30 scale shaking table test model of a power plant structure was fabricated. A comparative testing program was conducted using three seismic excitations on a model with and without CBDs. A finite element analysis model, replicating the conditions of the shaking table test, was constructed for comparison, and the shock absorption effects of CBDs subjected to 22 groups of far-field seismic action and 28 groups of near-field seismic action were analyzed. Finally, the influence of changes in the structural period on the seismic response of the CBD-equipped structure was studied. The results indicate that the use of CBDs in a coal-fired power plant structure, based on an optimization design method for multiple-tuned mass dampers (MTMDs), results in a significant reduction in the structure displacement response, displays a certain discreteness under different excitations, and maintains a certain damping stability even as the structural period changes. Overall, the use of CBDs is a promising prospect for improving the seismic performance of coal-fired power plant structures.


2014 ◽  
Vol 598 ◽  
pp. 743-746 ◽  
Author(s):  
Yeong Min Kim

This research performed dynamic tests on a 1/4 scale test model of a new-styled Korean traditional wooden house to study its dynamic characteristics. The dynamic tests were performed both by the impact hammer test and the shaking table test of an El-centro N-S seismic wave. Together with these dynamic tests, structural analysis was also performed and the results were compared. The natural frequency from the impact hammer test was slightly higher than that from the shaking table test. The natural frequency from the eigenvalue analysis was about 16~33% lower than that from both the impact hammer test and the shaking table test. It can be deduced that the rotational stiffness of joints of analysis model were somewhat underestimated than those of experiment model.


2010 ◽  
Vol 163-167 ◽  
pp. 981-986
Author(s):  
Li He ◽  
Xian Guo Ye

This paper presents the nonlinear dynamic simulation analysis of a shaking table test specimen, which was a twelve- story reinforced concrete frame and tested under base excitations representing four earthquake records of increasing intensity. Owing to the length constraint of the paper, three cases are used for the simulation. The numerical simulation of the test model is conducted utilizing the finite element analysis procedure CANNY, and the analysis results include the natural frequency, response history of the frame and the damage evolution. It is concluded from comparisons between experimental results and the numerical simulation ones that the latter matches well with the former, therefore the validity of the analytical method and model for simulation of RC frame shaking table test is proved.


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