Influence of ground motion selection method based on improved Latin hypercube sampling on seismic fragility of RC frame structure
Ji Jing1,2 Chen Shanshan2 Wang Yu2 Han Xiaolei1,2
1. State Key Laboratory of Subtropical Building Science, South China University of Technology, Guangzhou 510640, China;
2. School of Civil Engineering and Transportation, South China University of Technology, Guangzhou 510641, China
Abstract:In the study of structural seismic fragility, the commonly used ground motion selection methods are characterized by large discreteness of results and a large amount of calculation. Latin hypercube sampling method can effectively reduce the number of samples and improve their representativeness, however, when it is applied to discrete samples, sampling failure may occur easily. In this work, an improved Latin hypercube sampling method was proposed to select ground motions based on discrete intensity measures to improve the efficiency of fragility analysis as well as the representativeness of selected waves. It sorted the intervals after eliminating empty intervals and randomly selected points from them to replace the traditional coordinate component combination method. To investigate its effect on the structural fragility, the improved Latin hypercube sampling method was compared with the random sampling method. Taking 3 RC frame structures with different stories as examples, 500 ground motions were first selected as the input to obtain the datum structural fragility curves. Subsequently, 5,10,15, and 20 ground motions were sampled by the improved Latin hypercube sampling method of different dimensions, while 5,10,15,20,40,60,80, and 100 ground motions were sampled by the random sampling method, and the corresponding fragility curves were obtained. The difference and discreteness between the datum fragility curves and the corresponding fragility curves were studied and compared. It is found that under the same sampling accuracy, the improved Latin hypercube sampling method can reduce 67%~80% calculation workload compared with the random sampling method.
季静 陈珊珊 王雨 韩小雷. 改进拉丁超立方抽样选波法对RC框架结构地震易损性影响研究[J]. 土木工程学报, 2022, 55(3): 18-26.
Ji Jing Chen Shanshan Wang Yu Han Xiaolei . Influence of ground motion selection method based on improved Latin hypercube sampling on seismic fragility of RC frame structure. 土木工程学报, 2022, 55(3): 18-26.