构件锈蚀损伤的单层球面网壳抗震性能研究

A study on seismic performance of single-layer reticulated spherical shell with corroded members

构件锈蚀会引起网壳结构抗震性能退化,对于发生构件锈蚀的单层球面网壳结构,根据钢材锈蚀规律,提出采用时变模型分析、以结构损伤因子为评价指标的抗震性能退化规律研究方法。以K6型单层球面网壳结构为例,基于已有的钢材锈蚀模型,建立多龄期结构模型并进行动力时程分析,根据结构损伤因子得到了结构抗震性能随服役年限的变化规律。研究成果可为钢网壳结构全寿命设计、既有结构维护以及地震风险评估等提供理论依据。

Corrosion of steel members leads to seismic performance degradation of a single-layer spherical reticulated shell(SLSRS).For the SLSRS with corroded members,a method was proposed to study the seismic performance degradation.In the method,a time-varying model,based on the law of steel corrosion,is adopted to conduct structural seismic analysis and structural damage factors are used to assess the seismic performance.The method was illustrated by a case study of a Kiewitt-6 SLSRS.Firstly,the structure was modeled in different service times,according to existing time-functions of steel corrosion.Then,dynamic time-history response analysis was conducted for each structural model with damage factors calculated.Finally,the variation of damage factors reflected the degradation of structural seismic performance.The findings can contribute to the life circle design,the seismic assessment and the maintenance of steel reticulated shells.