高温后混凝土劈裂抗拉强度实验研究

Experimental study on splitting tensile strength of concrete after high temperature

为探究高温后混凝土劈裂抗拉强度变化,选取本地区常用的混凝土配合比,制作尺寸为100mm×100mm×100mm的C30和C40两种强度等级的混凝土试块共156块,分别在受火时间60min和90min、自然冷却和喷水冷却、高温后静置1d和14d的不同工况下进行火灾实验,得到不同受火时间、不同冷却方式、不同静置时间、不同强度等级影响下的高温后混凝土劈裂抗拉强度,进一步分析了不同工况的影响程度,为高温后建筑结构或构件的鉴定评估和加固设计提供依据。

In order to explore the variation of the splitting tensile strength of concrete after high temperature,156 pieces of C30 and C40 concrete blocks with the size of 100 mm×100 mm×100 mm were made by choosing the mix ratio of concrete commonly used in this area.The simulated fire tests were carried out under different conditions of 60 min and 90 min fire time,natural cooling and water spraying cooling,1d and 14d standing after high temperature.The splitting tensile strength values of concrete specimens with different fire time,cooling methods,standing time and strength grade after high temperature were obtained.The influence degree of different working conditions was further analyzed,which provides the basis for the appraisal and reinforcement design of building structures or components after high temperature.