The impact of ground motion inputs on the uncertainty of structural collapse fragility

被引：0
作者：
Ren Y.-F. [1 ]
Yin J.-H. [1 ]
Wen R.-Z. [1 ]
Ji K. [1 ]
机构：
[1] China Earthquake Administration, Key Laboratory of Earthquake Engineering and Engineering Vibration, China Earthquake Administration, Harbin
来源：
Gongcheng Lixue/Engineering Mechanics | 2020年 / 37卷 / 01期
关键词：
Ground motion input; Incremental dynamic analysis method; Strong motion record; Structural collapse fragility; Uncertainty;
D O I：
10.6052/j.issn.1000-4750.2019.01.0042
中图分类号：
学科分类号：
摘要：
The selection of ground motion input is one of the key procedures in the analysis of structural collapse fragility, but its impact on the uncertainty is usually ignored. The strong motion records from PEER database are divided into 9 groups by constraining the range of a single variable, which is one of the earthquake magnitude, distance and site parameters (M, R, VS30). A new index ISa is proposed to evaluate the difference of the relative energy of different groups of strong motion records. Incremental dynamic analysis (IDA) is conducted to analyze the collapse fragilities of three concrete frame structures, which are 3-floor, 8-floor and 15-floor with different natural periods, respectively. The fragilities derived from each group of the ground motion inputs are compared. They are also compared with the fragilities when the 22 records recommended by ATC63 are used as the ground motion inputs. The results show that the ground motion intensity representing the occurrence of collapse performance Sa(T1) decreases with the increase of earthquake magnitude, increase of epicentral distance and decrease of VS30, irrespective of the structures of concern. All three structures are more vulnerable to collapse if the strong-motion records at a far-field soft site in a large earthquake are selected as the seismic inputs, which is approximately consistent with the distribution of the relative energy of the ground motions represented by ISa. The comparisons of the two parameters SI and SImax among the different groups indicate that there is a relatively high sensitivity of epicentral distance for long-period structures, and the structural collapse fragility is more sensitive to the earthquake magnitude than to either the distance or the site condition. It is confirmed that a large uncertainty of the structural collapse fragility will be produced if the 22 records recommended by ATC63 are used as the ground motion inputs. For the sake of decreasing the uncertainty, it is suggested to use a method which can consider the seismic hazard of the site and the structural dynamic characteristics to select appropriate ground motion inputs when analyzing the collapse fragility of a structure. © 2020, Engineering Mechanics Press. All right reserved.
引用
收藏
页码：115 / 125
页数：10
相关论文
共 26 条
  • [1] Bertero V.V., Strength and deformation capacities of buildings under extreme environments, Structural Engineering and Structural Mechanics, 53, 1, pp. 29-79, (1977)
  • [2] FEMA 350, Recommended seismic design criteria for new steel moment-frame buildings, (2000)
  • [3] Yu X., Lu D., Wang G., Discussions on probabilistic seismic demand models, Engineering Mechanics, 30, 8, pp. 172-179, (2013)
  • [4] Wu Q., Zhu H., Fan J., Performance-based seismic fragility analysis of RC frame structures, Engineering Mechanics, 29, 9, pp. 117-124, (2012)
  • [5] Wang F., Li H., Seismic damage assessment procedure of structures by using simplified IDA, Engineering Mechanics, 35, 12, pp. 194-202, (2018)
  • [6] Yu X., Lu D., Seismic collapse fragility analysis considering structural uncertainties, Journal of Building Structures, 33, 10, pp. 8-14, (2012)
  • [7] Shi W., Ye L., Lu X., Et al., Study on the collapse-resistant capacity of RC frames with different seismic fortification levels, Engineering Mechanics, 28, 3, pp. 41-48, (2011)
  • [8] Wang M., Zhu A., Ding Y., Et al., Study on method for ground motion selection considering uncertainties of ground motions, China Civil Engineering Journal, 9, pp. 42-52, (2016)
  • [9] Li H., Cheng H., Wang D., Review of advances in seismic fragility research on bridge structures, Engineering Mechanics, 35, 9, pp. 1-16, (2018)
  • [10] Khorami M., Alvansazyazdi M., Shariati M., Et al., Seismic performance evaluation of buckling restrained braced frames (BRBF) using incremental nonlinear dynamic analysis method (IDA), Earthquakes and Structures, 13, 6, pp. 531-538, (2017)
123