Shake table tests of steel towers supporting extremely long-span electricity transmission lines under spatially correlated ground motions

2017 ◽  
Vol 132 ◽  
pp. 791-807 ◽  
Author(s):  
Li Tian ◽  
Xia Gai ◽  
Bing Qu
2020 ◽  
Vol 10 (19) ◽  
pp. 6969
Author(s):  
Chao Zhang ◽  
Guanghui Fu ◽  
Zhichao Lai ◽  
Xiuli Du ◽  
Piguang Wang ◽  
...  

This paper presents the results of shake table tests of a scaled long span cable-stayed bridge (CSB). The design principles of the scaled CSB are first introduced. The first six in-plane modes are then identified by the stochastic subspace identification (SSI) method. Furthermore, shake table tests of the CSB subjected to the non-pulse near-field (NNF) and velocity-pulse near-fault (PNF) ground motions are carried out. The tests indicated that: (1) the responses under longitudinal uniform excitation are mainly contributed by antisymmetric modes; (2) the maximum displacement of the tower occurs on the tower top node, the maximum acceleration response of the tower occurs on the middle cross beam, and the maximum bending moment of the tower occurs on the bottom section; (3) the deformation of the tower and girder subjected to uniform excitation is not always larger than that subjected to non-uniform excitation, and therefore the non-uniform case should be considered in the seismic design of CSBs.


2007 ◽  
Vol 34 (11) ◽  
pp. 1381-1392 ◽  
Author(s):  
C. S. Meisl ◽  
K. J. Elwood ◽  
C. E. Ventura

Given sufficient anchorage to the diaphragms, out-of-plane walls in unreinforced masonry (URM) buildings have been shown to crack above midheight and then rock as two rigid bodies. This study investigates the sensitivity of the rocking response to the type of ground motion and the quality of the wall construction. Shake table tests were conducted on four full-scale multi-wythe walls, all with a height to thickness (h/t) ratio of 12 but of varying construction quality and subjected to three different ground motions. All walls experienced cracking at less than one half of the 2005 National Building Code of Canada (NBCC) level for Vancouver, but exhibited a stable rocking behaviour without collapse beyond a ground motion 1.5 times the 2005 NBCC level.


2007 ◽  
Vol 23 (4) ◽  
pp. 893-908 ◽  
Author(s):  
Iman Sharif ◽  
Christopher S. Meisl ◽  
Kenneth J. Elwood

Unreinforced masonry (URM) walls with sufficient anchorage to the diaphragms will crack above mid-height when subjected to out-of-plane ground motions. This study investigates the sensitivity of the out-of-plane response to varying height-to-thickness ( h/ t) ratios for URM walls connected to rigid diaphragms. ASCE 41, Seismic Rehabilitation Standard, provides guidelines for permissible h/ t ratios for out-of-plane URM walls. To assess these limits, a rigid-body numerical model, calibrated to full-scale shake table tests, was used. The focus of the analysis was to identify the minimum h/ t ratio that would cause collapse of the wall when subjected to seismic shaking. The analysis was performed for 80 input motions and accounted for variability in the crack location. The results of the study suggest that the probability of collapse is dependent on the site class and that walls with limited overburden and satisfying the h/ t limits in ASCE 41 have a very low probability of collapse.


2021 ◽  
pp. 875529302098801
Author(s):  
Michalis F Vassiliou ◽  
Cihan Cengiz ◽  
Matt Dietz ◽  
Luiza Dihoru ◽  
Marco Broccardo ◽  
...  

Conventional validation of analytical and numerical models in Earthquake Engineering involves the comparison of numerically simulated response time histories to experimentally obtained benchmark responses to the same earthquake excitations. As the seismic design problem is inherently stochastic, an alternative, statistical, and easier-to-pass validation procedure has been suggested. As an example, numerical and analytical models may fail to predict the planar rocking response of a rigid block to a specific ground motion, but they can be proven quite successful in predicting the statistical distribution of the maxima of that response to an ensemble of ground motions. This article describes the publicly available data obtained from a series of 226 shake table tests of a 3D rocking podium structure, designed at ETH Zurich and carried out at EQUALS Lab, University of Bristol. This well-documented dataset is the largest one involving a shake table and can be used to statistically validate analytical and numerical models of rocking structures.


Author(s):  
Wen-I Liao ◽  
Juin-Fu Chai

Seismic performance of nonstructural elements such as the raised floor system has not attracted much attention. However, damage of expensive equipments that stand in the raised floor system of high-tech FAB was often observed during past earthquake in Taiwan area. This will result in huge loss of manufacturing functions and properties for the high-tech industry. There is a need to understand the dynamic characteristics of the raised floor system for future seismic protection. This paper presents the seismic performance of raised floor system by shake table excitations. The tested raised floor system was a pedestal-stringer frame structure, and supporting a simulated equipment. This raised floor system was the typical system that frequently used in Taiwan semi-conductor FAB. The input motions for the shake table tests were the waffle-slab floor acceleration responses of a typical semi-conductor FAB by input simulated ground motions. The simulated ground motions are base on the phase spectrum and the maximum potential earthquake of site located at Taiwan Hsin-Chu Science Park. The dynamic characteristics include the acceleration amplification and dependence of input motions by raised floor system was studied and discussed. This study also employee the finite element package to carry out numerical simulation on seismic responses of raised floor systems and compared with the experimental data, and show that the proposed simulation model was very excellent.


2021 ◽  
pp. 102886
Author(s):  
Jianyang Xue ◽  
Pengchun Hu ◽  
Fengliang Zhang ◽  
Yan Zhuge

2010 ◽  
Vol 132 (3) ◽  
Author(s):  
Izumi Nakamura ◽  
Akihito Otani ◽  
Masaki Shiratori

Pressurized piping systems used for an extended period may develop degradations such as wall thinning or cracks due to aging. It is important to estimate the effects of degradation on the dynamic behavior and to ascertain the failure modes and remaining strength of the piping systems with degradation through experiments and analyses to ensure the seismic safety of degraded piping systems under destructive seismic events. In order to investigate the influence of degradation on the dynamic behavior and failure modes of piping systems with local wall thinning, shake table tests using 3D piping system models were conducted. About 50% full circumferential wall thinning at elbows was considered in the test. Three types of models were used in the shake table tests. The difference of the models was the applied bending direction to the thinned-wall elbow. The bending direction considered in the tests was either of the in-plane bending, out-of-plane bending, or mixed bending of the in-plane and out-of-plane. These models were excited under the same input acceleration until failure occurred. Through these tests, the vibration characteristic and failure modes of the piping models with wall thinning under seismic load were obtained. The test results showed that the out-of-plane bending is not significant for a sound elbow, but should be considered for a thinned-wall elbow, because the life of the piping models with wall thinning subjected to out-of-plane bending may reduce significantly.


2021 ◽  
Vol 247 ◽  
pp. 113087
Author(s):  
Jui-Liang Lin ◽  
Wen-Hui Chen ◽  
Fu-Pei Hsiao ◽  
Yuan-Tao Weng ◽  
Wen-Cheng Shen ◽  
...  

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