人民长江2023，Vol.54Issue(12)：202-210,224,10.DOI:10.16232/j.cnki.1001-4179.2023.12.027
考虑坝体材料参数随机性的拱坝易损性分析
Vulnerability analysis on arch dams based on spatial variability of dam materials
摘要
Abstract
The process of construction and the quality of concrete materials can lead to the randomness of arch dam materials.To evaluate the influence of the randomness of dam concrete materials on the seismic performance of arch dams under strong ground motions,taking the Baihetan high arch dam as a case,we investigate the relation among the relevant length that represents material heterogeneity,the mean value of material parameters and the failure of arch dams.The endurance time analysis(ETA)is used to generate the artificial ground motion time history.It is assumed that the dam material parameter value follows the uniform distribution within a specific interval.At the same time considering the local continuity of the dam material,the correlation length is introduced into the uniform distribution formula.Based on covariance matrix decomposition and center point discretization tech-nology,we establish a finite element model of the arch dam random field corresponding to different correlation lengths.And its dy-namic response under the ground motion is analyzed.The relative displacement,transverse joint opening and damage volume ratio are selected as the damage evaluation indexes.The time-varying probability density curves of each index are calculated based on the probability density evolution method(PDEM)and the direct probability integration method(DPIM),and the failure probabil-ity curves of different indexes are calculated to evaluate the failure probability of the dam body under different peak ground accel-eration(PGA).The analysis results show that after considering the randomness of the dam material,the dam damage distribution is scattered,and the analysis results under different conditions are more discrete.The damage is mainly affected by the correlation length and the mean value of material parameters.The longer the correlation length is,the better the seismic performance of the dam body is.关键词
混凝土拱坝/耐震时程法/材料随机性/概率密度/失效概率Key words
concrete arch dam/endurance time analysis/randomness of materials/probability density/failure probability分类
建筑与水利引用本文复制引用
徐强,姚文斌,陈健云,张天然,曾祥兴..考虑坝体材料参数随机性的拱坝易损性分析[J].人民长江,2023,54(12):202-210,224,10.基金项目
国家自然科学基金重大项目子课题"混凝土坝枢纽潜在失效模式与灾变机理研究"(52192672) （52192672）
