无梁楼板的抗倒塌性能试验研究及分析  

Collapse Experiment Research and Analysis of a RC Flat Plate

作　　者：张凡榛[1] 易伟建[1] 

机构地区：[1]湖南大学土木工程学院,湖南长沙410082

出　　处：《湖南大学学报（自然科学版）》2010年第4期1-5,共5页Journal of Hunan University:Natural Sciences

基　　金：国家自然科学基金资助项目(50678064)

摘　　要：偶然荷载作用下,预测结构可能发生的破坏并提供新的荷载传递路径,是结构抗倒塌设计的重要内容.对一4层钢筋混凝土框架结构模型的第1层板,采用静载试验来模拟无梁楼板结构下层支撑构件的失效.通过机械千斤顶对板分级施加荷载来模拟上部结构荷载,随着千斤顶施加荷载的不断增加,楼板受拉面出现放射状裂缝,板的压力薄膜作用使得其承载能力比屈服线理论计算值提高40%左右.楼板中间突然出现倒圆锥形破坏区域后,结构原有的荷载传递机制发生了转换,钢筋形成的索网能承担上部荷载约为屈服线理论计算值的65%.基于试验结果对试验模型破坏机理进行了分析和计算,并提出依靠薄膜作用实现无梁楼板结构抵抗倒塌的途径.To understand the structural failure-mechanism and seek alternative load paths under accidental load action is an important aspect in collapse-resistant design of structures. A quasi-static experimental method was proposed to simulate the sudden column loss in an existing 4-story reinforced concrete flat plate frame structure. The gravity load of the upper structure was applied step by step to the plate＇s center with a mechanical jack. The load carrying capacity was enhanced by around 40~/~ higher than the value calculated with the field-line theory due to the compressive membrane action. Later, an inverted conical damage region appeared, the structure of the original load-transfer mechanism changed, and the remaining upper load was approximately 0. 65, which was taken by the catenary action of reinforcement. Based on the experiment results, the failure-mechanism of structure was ana- lyzed, the collapse-resistant of flat plate was explored and the compressive membrane/tension membrane action of flat plate was discussed.

关 键 词：无梁楼板 框架 悬索 薄膜作用 连续倒塌 倒塌试验 塑性铰线 

分 类 号：TU375.2[建筑科学—结构工程] TU317.1