隔震支座下支墩(柱)截面及配筋的构造优化

Structural Optimization of Section and Reinforcement of Isolation Bearing Lower Pier/Column

隔震建筑的隔震层下支墩(柱)钢筋与下预埋板及其埋件互相阻挡和交叉,不可避免的引起下预埋板定位偏差、混凝土难以浇筑密实。为提高下预埋板安装精度和下支墩混凝土密实度,通过调研国内已建成的部分隔震建筑,将相关规范要求与下支墩(柱)构造设计、施工现状进行比较分析,提出了下支墩(柱)截面设计、纵筋长度、配箍形式、带拉梁下支墩节点构造的改进方法和优化。研究结果表明:下支墩(柱)采用较大截面、分批截断纵筋、纵筋末端直锚、配置多边形复合箍、降低拉梁面标高等构造和设计措施能减少钢筋冲突,有效提高了下预埋板安装精度和下支墩(柱)混凝土密实度。

The steel bars of the lower supporting pier/column of the seismic isolation layer and the lower embedded slab and its embedded parts block and cross each other,which inevitably causes the positioning deviation of the lower embedded slab and the concrete is difficult to pour and compact.In order to improve the installation accuracy of the lower pre-embedded slab and the concrete compactness of the lower buttress piers,by investigating some of the seismic isolation buildings that have been built in China,the relevant code requirements are compared and analyzed with the lower buttress(column)design and construction status.The results from modified method and optimization of pier(column)section design,longitudinal reinforcement length,hooping form,and joint structure of lower buttress pier with tension beam were compared.The research results show that the structure and design measures such as larger cross-section,truncated longitudinal reinforcement in batches,straight anchors at the end of longitudinal reinforcement,configuration of polygonal composite hoops,and lowering of the surface elevation of the tension beam can reduce the conflict of steel bars and effectively improve the structure and design measures of the lower support pier/column.The installation accuracy of the lower embedded slab and the concrete density of the lower supporting pier/column have been improved.