高温下钢筋与混凝土本构关系的试验研究

An Experimental Study of Constitutive Relationship between Reinforced Bar and Concrete Under Elevated Temperature

本文对30个混凝土T形截面柱体和40根钢筋试件在常温100～800℃范围内的不同温度和荷载同时作用下的强度、变形、弹性模量和应力-应变关系等进行了实验和理论研究工作。探讨了高温和荷载共同作用下的变化规律,着重分析了不同温度和荷载共同作用下的破坏特征,及其对钢筋和混凝土的弹性模量、极限拉压应变、强度等的影响和应力-应变关系,经过理论分析和推导,建立了简洁实用的公式,并用计算机计算,表明计算与试验结果符合较好。此外,本文也讨论了钢筋试件在受不同温度作用后,进行冷却一昼夜,然后再进行加载的情况。

This paper studies the material strength, deformation, elasticity modulus and stress-strain relationship based on the testing specimens, which consist of 30 T-type section concrete and 40 steel bar specimens respectively under the conditions of normal atmospheric temperature and the temperatures ranging from 100℃ to 800℃ combined with various static loads. Emphasis was laid on the analysis of failure characterestics, modulus of elasticity for concrete and steel bars, ultimate tension and compression strain and strength under the action of elevated temperature and load simultaneously. The proposed calculation formula in this paper can be used in practice and the computer employed shows that the calculated results agreed fairly with the test ones. In addition, the case of steel specimens colded 24hr after acting in different temperatures and then loaded again is also discussed.