预应力混凝土连续板不同跨受火火灾行为  

Behaviours of unbonded prestressed continuous concrete slabs with middle span and edge span subjected to fire in-order

作　　者：袁爱民[1] 董毓利[2] 戴航[3] 李延和[4] 

机构地区：[1]河海大学土木工程学院,南京210098 [2]哈尔滨工业大学土木工程学院,哈尔滨150001 [3]东南大学土木工程学院,南京210096 [4]南京工业大学加固与鉴定中心,南京210009

出　　处：《哈尔滨工业大学学报》2008年第10期1633-1638,共6页Journal of Harbin Institute of Technology

基　　金：国家自然科学基金资助项目(50178034);国家重点基础研究专项经费资助项目(2001CB409603);国家自然科学基金重大国际合作研究项目(5032120156)

摘　　要：为了研究三跨连续板不同跨依次受火作用下的火灾行为,对4块尺寸为12.6m×1.5m×0.12m的无粘结预应力砼连续板进行了火灾试验.试验考虑了连续板中跨和边跨在不同时间段发生火灾及负弯矩区负筋长度两种因素,在实现ISO标准升温的前提下,给出了板中水在火灾中全过程变化现象以及板在火灾作用下裂缝发生、扩展及最终形式,重点研究了板的变形、破坏机构的形成、预应力筋中拉力的变化,板中温度场以及支座支反力的重分布情况.通过对试验结果的分析,揭示了破坏机构形成和支反力重分布的原因,指出了板中温度场的分布情况及预应力筋拉力的变化特征.To study the behaviours of unbonded prestressed continuous concrete slabs with middle span andedge span subjected to fire in-order, four unbonded prestressed concrete continuous slabs with the size of 12.6m × 1.5m ×0. 12m have been tested. Two important factors were taken into accout in the test. One was middle span and edge span subjected to fire in-order, the other was the length of nagative reinforcing bar existing in the zone of negative moment at the middle support. Based on the premise that the ISO time-temperature curve would achieve, the whole variety processs of water in slab and the slab cracking during the course of fire test were presented. The investigation was carried out with the emphasis on the deformation of slab, the formation of failure framework, the variety of prestressing in prstressing strand, the temperature fields in slab and the redistribution of support force. By the analysis of the results, the reasons of the formation of destruction framework and the redistribution of support force were found. The distribution of temperature fields of slabs and the variable regularity of prestressing were also given.

关 键 词：无粘结预应力混凝土连续板 火灾试验 负筋长度 

分 类 号：TU378[建筑科学—结构工程] TU352.503