拱桥钢管混凝土温度场分析

Concrete Temperature Field Analysis for Concrete-filled Steel Tubes Arch Bridge

浇筑相同尺寸的钢管混凝土和素混凝土试件并放置在温度模拟装置中,通过模拟西北地区日平均大气温度进行试件截面温度场试验。试验时测定管内相同位置处钢管混凝土和素混凝土的温度变化,得到了二者的应力、应变曲线,进一步分析了该温度场中钢管混凝土的脱粘情况。结果表明:钢管混凝土和素混凝土试件截面温度变化与大气温度变化相比有明显的滞后性,且由试件表面到中心,温度变化的滞后性越来越明显;在该温度场下钢管与核心混凝土之间不仅不会发生脱粘,而且当外界气温达到峰值时钢管对核心混凝土的约束作用最大。

The same size specimens of the concrete-filled steel tube（CFST） and plain concrete were cast and placed in a temperature simulator. The temperature field test of the specimen section was carried out by simulating the daily mean air temperature in Northwest China. The stress and strain curves were obtained by measuring the temperature variation of CFSTand plain concrete in the same position in the tube,the debonding condition of CFSTwas further analyzed. The results showthat the temperature variation of the section of CFSTand plain concrete have obvious hysteresis compared with the atmospheric temperature. Fromthe surface to the center of the specimen,the hysteresis of temperature variation is more and more obvious. In this temperature field,not only does not occur debonding between the steel tube and the core concrete,but also the restriction effect of the steel tube to the core concrete is the highest when the outside temperature reaches the peak value.