外廊式RC框架结构教学楼的抗震性能研究

Study on seismic behavior of side corridor RC frame school building

以在2008年汶川特大地震中倒塌的漩口中学综合教学楼震害为背景,对典型外廊式RC框架结构教学楼的抗震性能及倒塌机理进行了研究。以漩口中学教学楼为原型结构,选取最具代表性的三榀横向框架单元:中间榀纯框架、山墙边榀满布填充墙框架及中间榀较大一跨满布填充墙框架,设计制作了3个缩尺比为1/2的考虑楼板翼缘及填充墙作用的单层两不等跨框架试验模型,填充墙材料包括传统的实心黏土砖及目前常用的加气砌块。震害分析及试验研究表明:①现浇楼板的存在是漩口中学教学楼产生"强梁弱柱"式破坏机制的重要原因;②填充墙对框架结构的破坏模式、延性、强度及刚度产生了显著的影响;③当填充墙存在时,外廊柱的存在加重了中柱的破坏程度,试验结果表明结构的倒塌始于中柱,与漩口中学教学楼的倒塌机制吻合。

Based on the investigation on the collapsed Xuankou middle school buildings in 2008 Wenchuan earthquake, the collapse mechanism of typical side corridor school building is studied in this paper. Three of typical transverse frame units of the collapsed building are selected as the prototype, and three 1/2 scale, single-story, two-bay specimens with floor have been tested. Specimen 1 is designed to simulate the intermediate frame without any masonry infill, specimen 2 to simulate the gable frame with traditionally used clay brick masonry fully in-filled in both two spans, and specimen 3 to simulate the intermediate frame with popularly used aerated concrete block masonry fully in-filled in the larger span only. The quasi-static test results for the three specimens show that ： （ 1 ） The unexpected failure mechanism of ＂ strong beam and weak column＂ happened in all specimens, the existence of the RC floor cast in-situ is the major cause; （2） Masonry infill take critical role to specimen＇ s lateral stiffness, strength, ductility and the failure pattern; （3） The existence of masonry infill accentuated the damage severity of the central column, the structural collapse initiated from the central column. The collapse pattern consists well with buildings. the phenomenon observed in the collapsed Xuankou school