空心墩地震损伤评估及性能水准量化研究  

Study on seismic damage assessment and performance level quantification of hollow pier

作　　者：漆启明 邵长江[1,2] 胡晨旭 韦旺 肖正豪 Qi Qiming;Shao Changjiang;Hu Chenxu;Wei Wang;Xiao Zhenghao(Civil Engineering School,Southwest Jiaotong University Chengdu 610031,China;National Engineering Laboratory for Disaster Prevention Technology in Land Transportation,Southwest Jiaotong University,Chengdu 610031,China;West Investment Co.,Ltd.,of CCTEB,Chengdu 610041,China)

机构地区：[1]西南交通大学土木工程学院,四川成都610031 [2]西南交通大学陆地交通地质灾害防治技术国家工程实验室,四川成都610031 [3]中建三局西部投资有限公司,四川成都610041

出　　处：《土木工程学报》2020年第11期116-128,共13页China Civil Engineering Journal

基　　金：国家自然科学基金(51978581,51178395);四川省应用基础研究重点项目(2017JY0059)。

摘　　要：准确量化空心墩损伤状态是确定其抗震性能水准的基础,也是基于性能抗震理论的重要研究内容。为此,基于19个空心墩拟静力试验结果,对空心墩损伤特点、破坏机理进行深入细致分析,确立空心墩性能水准划分及其与各性能指标的量化关系,并根据各墩损伤演化曲线探讨既有损伤模型对空心墩震损评估的适用性。结果表明:与实心墩相比,空心墩弯剪耦合效应显著,塑性损伤范围更广,纵筋屈曲及核芯混凝土压溃现象更严重;由于墩身截面刚度变化,圆端空心墩易损部位由墩底上移至倒角上缘附近;利用裂缝宽度、钢筋/混凝土应变、损伤分量(强度/刚度退化、残余位移)可以较好地量化空心墩基本完好、轻微损伤、中等损伤、严重损伤、控制倒塌五个性能水准;各损伤模型的演化曲线差异显著,相同状态下所得损伤指数离散性较大;Park-Ang模型能够合理描述空心墩加载至中等损伤时的状态,但高估了空心墩严重损伤的程度;曾武华模型与试验结果趋于一致,且离散性较小,可作为混凝土空心墩的地震损伤评估模型。Accurate quantification on the damage state of a hollow pier is the basis of determining its seismic performance level, and also an important content in the performance-based seismic framework.Therefore, based on the quasi-static test results of 19 hollow piers, the damage characteristics and evolution mechanism of hollow columns are analyzed in depth.The classification of performance levels for hollow specimens is conducted and the quantified relationship between the performance levels and indexes are established.Based on the evolution curves of damage indices, the applicability of some existing damage models to the seismic damage assessment of hollow piers is discussed.The results show that compared with solid-section pier, the shear-flexural coupling action of hollow pier is more remarkable.Moreover, the plastic damage scope is larger and the phenomena of longitudinal rebar yielding and crushing of core concrete is more severe.Due to the varying sectional stiffness along pier, the vulnerable part of round-ended hollow pier moves from the pier bottom to the upper edge of internal chamfer.The five performance levels of hollow pier, namely, intact, minor damage, moderate damage, major damage and collapse control, can be well quantified by using the crack width, reinforcement/concrete strain and damage components(strength/stiffness degradation and residual displacement).The damage curves of these models differ remarkably, and the scatter of the damage indices under the same state is evident.The Park-Ang model can reasonably describe the process from initial loading to moderate damage, but it overestimates the severe damage state of the hollow pier.It is observed that Zeng’s model agrees well with the test results with less scatter, indicating that the proposed formula can be used for seismic damage assessment on concrete hollow pier.

关 键 词：桥梁工程 空心墩 拟静力试验 损伤模型 性能水准 

分 类 号：U442.55[建筑科学—桥梁与隧道工程]