摘要
为了研究膨胀剂掺量和含钢率对钢管混凝土徐变性能的影响,在(20±1)℃、相对湿度(60±5)%时,测试30%荷载水平下,膨胀剂掺量分别为0%,4%,8%以及含钢率分别为0.038,0.066,0.092时钢管混凝土的徐变应变。试验结果表明:含钢率一定时,徐变应变随着膨胀剂掺量的增加而降低。膨胀剂掺量一定时,徐变应变随着含钢率的增加而降低。将徐变试验后的钢管混凝土进行切割,对其核心混凝土采用孔结构测试仪进行微观结构观测,分别进行了气泡数目、气泡弦长、硬化混凝土空气含量等的观测。观测结果表明:钢管混凝土掺入膨胀剂后,在钢管的限制作用下,核心混凝土更加密实,其构件强度提高,从而使其徐变应变降低。
The specific creep strain of concrete filled steel tube incorporated with expansive agent proportion of 0%,4%,8% and steel ratio of 0. 038,0. 066,0. 092 was tested under stress strength ratios of 30% in order to clarify the effect of expansive agent proportion and steel ratio on creep behavior. The tests were made under controlled temperature（ 20 ± 1） ℃and humidity（ 60 ± 5） % conditions. Test results show that the creep strain of concrete filled steel tube decreases with the increase of expansive agent proportion at constant steel ratio and also decreases with the increase of steel ratio at constant expansive agent proportion. At the same time after creep test of concrete filled steel tube through cutting,micro-structure observation of core concrete was carried out by pore structure tester,including the number of air bubble,length of bubble chord,air content of hardened concrete observation,and etc. Observation shows that when concrete filled steel tube is mixed with expansive agent,under the action of the limitations of the steel tube,core concrete is more compact,the component strength increases,thus the creep strain of the component decreases.
出处
《建筑结构》
CSCD
北大核心
2014年第22期41-44,共4页
Building Structure
基金
长江学者和创新团队发展计划项目(IRT1139)
兰州交通大学青年科技基金项目(2012028)
关键词
钢管混凝土
膨胀剂掺量
含钢率
徐变
concrete filled steel tube
expansive agent proportion
steel ratio
creep
