钢管自应力混凝土短柱长期荷载作用下变形性能研究

Study of deformation behaviors of self-stressing concrete-filled circular steel tubular short column under long term loading

采用硫铝酸盐自应力水泥配制的膨胀混凝土代替普通混凝土浇筑于钢管中形成了钢管自应力混凝土结构,对7根钢管自应力混凝土短柱试件长期荷载作用下的变形性能进行了试验研究.在此基础上,考虑了自应力的初始约束效应,基于ACI209委员会推荐的混凝土徐变系数,采用龄期调整的有效模量法,对试件在长期荷载作用下的变形曲线进行了计算,试验结果和计算结果基本吻合;系统分析了自应力、含钢率、轴压比等因素对徐变变形的影响,研究结果表明:钢管自应力混凝土轴压短柱的徐变变形要大于普通钢管混凝土轴压短柱的徐变变形.

Self-stressing concrete-filled steel tube（SSCFST） is made by sulfoaluminate-type expansive concrete instead of common concrete.7 SSCFST specimens were tested to investigate the effects of long-term loading on deformation behaviors of the members.Taking the initial constrained effects of self-stressing into account,using the creep coefficients proposed by ACI209 Committee,the effective modulus method adjusted by age of concrete is used to predict the load-axial strain curves.The calculation and test results have a basal accordance.Self-stressing,steel ratio,axial compression ratio,the factors influencing the creep deformation are systemically analyzed.The results indicate that SSCFST short columns have larger creep deformation than common concrete-filled steel tubular columns.