预应力施加过程中混凝土的徐变变化  

Study on Concrete Creep Developed During Stressing

作　　者：亢景付[1] 彭小平[2] 

机构地区：[1]天津大学建筑工程学院,天津300072 [2]天津住宅建设发展集团有限公司,天津300050

出　　处：《天津大学学报（自然科学与工程技术版）》2003年第2期210-214,共5页Journal of Tianjin University：Science and Technology

摘　　要：结合工程实测资料,对预应力施加过程中混凝土的徐变变化规律进行了探讨和分析.研究结果表明,混凝土在预应力施加过程中产生的徐变应变与应力σ和持荷时间t成直线关系.对于需要数天时间才能完成预应力施加的大型混凝土结构,在进行预应力效果分析时可把整个张拉过程划分为若干个张拉时段和停置时段,分别记录每个时段观测仪器的读数变化,按ε0=α∑σiti来近似计算预应力施加过程中徐变应变.The development of concrete creep during and after stressing was investigated, based on the monitored data of Xiao Langdi prestressed sediment tunnel liner. It demonstrates that the concrete creep developed during stressing is linearly related to the existing stress σ and the loading time t. The percentage of concrete creep in the total strain is relatively large and can't be ignorable. For the engineering structures that several days will be needed to complete the stressing. According to the stressing program a correct evaluation to the prestressing effects can be made by dividing the total stressing period into several stressing time intervals and staying time intervals and by recording the strain variation developed in each time interval. Thus, the concrete creep can be calculated by the formula ε0=α∑σiti.

关 键 词：预应力结构 徐变 应变变化 

分 类 号：TU378[建筑科学—结构工程]