配筋梯度混凝土梁极限承载力分析

摘要

采用高强高性能混凝土替换普通混凝土压区形成了配筋梯度混凝土受弯结构构件,该类新型结构构件可达到使相对受压区高度易于满足截面容许受压区高度的目的.结合拉压区为异强混凝土的配筋梯度混凝土梁试验,获得了极限压应变、极限变形以及纯弯段箍筋应变等,着重分析了承载能力极限状态下平截面假定的适用性以及两类混凝土的整体工作性能.提出了配筋梯度混凝土受弯结构构件正截面承载力计算方法,探索了该类梁塑性铰转动能力与曲率延性.为配筋梯度混凝土受弯结构构件承载能力极限状态计算提供了理论支持与试验依据.%The reinforced gradient concrete beam consists of normal concrete tensile region and high concrete compressive zone.This new flexural member may easily satisfy the requirement of the depth of the limiting compressive zone in reinforced concrete flexural element.The experiment of simple beam with reinforced gradient concrete was carried out.Ultimate compressive strain,maximum deflection and strains of round stirrup are measured.Assumption on plane before loading remaining plane under ultimate load and harmony of two concretes were analyzed emphatically.The calculation method of ultimate load-bearing capacity of such flexural member is proposed.Plastic hinge rotation capacity and curvature ductility are analyzed.It can be served as calculation for ultimate limit state of reinforcing gradient concrete flexural members.