侧向约束多层预应力砼框架三阶段分析法

Three-stage analysis method of lateral restraint concrete frame structure with multi-storey pre-stress

为解决侧向约束问题,提出了侧向约束柱作用于预应力砼框架结构的三个阶段。通过对三阶段的分析,将侧向约束对预压力传递影响看成由结构形式、构件截面属性和预压力造成的预应力损失σlcon。将等效弹簧模型扩展到多层侧向约束砼框架,计算出侧向约束框架柱对预压力传递影响系数ηi,j。利用三阶段理论中的第三阶段推导出正截面极限承载力验算公式。通过实际算例同其他公式相比较分析,给出了一种实用方便的正截面极限承载力验算公式。

Aimed at overcoming the problem of lateral restraint column, this paper introduces the division of the influence of the lateral restraint column on the pre-stressed concrete frame structure into three stages. The analysis of three stages leads to the possibility that the effects of lateral restraint on transfer of pre-stress can be regarded as the pre-stress loss(σlcon), due to structure type, properties of member section and pre-compress force. The coefficient(ηi,j) of effects for lateral restraint frame column on transfer of pre-compress stress is calculated by expanding the equivalent spring model to multi-storey lateral restraint concrete frame structure. The formula of normal section flexural load-bearing capacity is given by the third stage in theory of three-stage. The analysis and comparison with other formula by calculation examples offer a more convenient and practical formula for normal section flexural load-bearing capacity.