高温后密肋复合墙体框格单元剩余承载力

Residual Bearing Capacity of Multi-Ribbed Composite Wall Cell After High Temperature

摘要:

密肋复合墙体由钢筋混凝土框格与内嵌的轻质加气混凝土砌块组成,是密肋复合墙结构的主要受力构件，其框格单元是最基本的受力单元.根据密肋复合墙体各材料高温后的力学性能,对框格单元进行数值模拟.按照ISO834国际标准升温曲线,得到在不同火灾加载方案下的温度场云图.以此为基础,对框格单元在竖向荷载下的承载力进行数值模拟分析,比较了单面受火和双面受火后的力学性能.结果表明，随着受火时间的增加,剩余承载力下降的速度是先快后慢；在施加竖向位移荷载时,一面受火的框格单元更易出现面外位移，因此比双面受火的框格单元先达到极限荷载.

Abstract:

The multi-ribbed composite wall consists of the frame made of reinforced concrete rib and lightweight aerated concrete block, which are the two principal bearing members. Frame cell is the essential weighted element. Therefore, numerical analysis on frame cell was conducted according to the thermodynamic performance of each material in the multiribbed composite wall. Finite element analysis was carried out based on temperature field contours in different fire loads with ISO834 international heating curves. It was found that the rate of residual bearing capacity increased and then decreased as the heating time increased and mechanical performance are different between one side and double side by the fire. The heated side achieved ultimate load earlier under vertical displacement load. Because of the damage of the fire, the multiribbed composite wall cell is more likely to have outplane displacement.