随机地震作用下伞型索网结构抗震可靠度研究  

Research on Seismic Reliability of Umbrella Cable Net Structure Under Random Earthquake

作　　者：张邦爱 卓小丽 ZHANG Bang′ai;ZHUO Xiaoli(Hunan Communications Research Institute Co.,Ltd.,Changsha,Hunan 410015,China;Research and Development Center on Emergency Information Support Technologies and Equipment for Transport Safety,Changsha,Hunan 410015,China;Guangxi Transportation Science Group Co.,Ltd.,Nanning,Guangxi 530000,China)

机构地区：[1]湖南省交通科学研究院有限公司,湖南长沙410015 [2]交通运输安全应急信息保障技术及设备交通运输行业研发中心(长沙),湖南长沙410015 [3]广西交科集团有限公司,广西南宁530000

出　　处：《公路工程》2023年第1期141-148,共8页Highway Engineering

基　　金：广西科技计划和人才专项项目(桂科AD19245152)。

摘　　要：针对目前在索网结构随机地震作用下可靠度分析中未考虑地震激励的非平稳性与索网结构非线性的耦合作用的问题,基于非平稳地震动过程模拟的谱-随机函数方法,生成584条随机地震动样本并输入至ANSYS有限元模型中,采用概率密度演化方法(PDEM)分析其在随机地震作用下的响应,结合等价极值分布思想计算了动力可靠度。以某伞型索网结构为例,计算结果表明:采用概率密度演化方法对伞型索网结构进行随机地震动分析,其响应均值和标准差与10000次Monte Carlo抽样得出的结果拟合较好,相对误差二范数分别为1.03%和3.01%,均在误差范围之内;以伞型索网结构最大节点位移限制为0.3 m作为失效指标,在8度设防地震作用下,II、III、IV类场地条件下结构可靠度依次为2.6874、2.3252、2.1540;结构的动力可靠度为0.7104。In view of the fact that the deterministic dynamic response is still used in our country to analyze the safety performance of the cable network structure under random earthquakes,the coupling effect of the non-stationarity of seismic excitation and the nonlinearity of the cable network structure is not considered.Based on the spectral representation-random function method of non-stationary ground motion simulation,this paper generates 584 random ground motion samples and substitutes them into the ANSYS finite element model.The probability density evolution method(PDEM)is used to analyze its response under random earthquakes,and combined the equivalent extreme value distribution idea calculates its dynamic reliability.Taking the umbrella cable net structure as an example,the calculation results show that the random ground motion analysis of the umbrella cable net structure using the probability density evolution method shows that the response mean and standard deviation fit well with the results obtained from 10000 Monte Carlo sampling.The relative error of the two norms are 1.03%and 3.01%respectively,and both are within the error range;the maximum node displacement of the umbrella cable net structure is limited to 0.3 m as the failure index,under the action of the 8 degree fortified earthquake,the structural reliability under categoryⅡ,Ⅲ,andⅣsite conditions are 2.6874,2.3252,and 2.1540 in sequence;under the action of a rare earthquake of 8 degrees,the dynamic reliability of the structure is 0.7104.Therefore,the dynamic nonlinearity of the umbrella-type cable net structure is effective for reliability.The degree of influence is very large.

关 键 词：索网结构 非平稳性 随机地震 PDEM 动力可靠度 

分 类 号：TU352.11[建筑科学—结构工程]