配筋超高强混凝土柱徐变试验研究

Experimental research on creep of reinforcement ultral high strength concrete columns

对6个混凝土强度等级为C80~C120的配筋超高强混凝土柱进行了徐变试验,比较了不同强度混凝土的徐变特性。根据混凝土变形计算公式以及混凝土与钢筋之间的力平衡条件与变形协调条件,推导出钢筋对混凝土徐变系数的影响系数计算公式。对常用的4种徐变模型进行了比较分析,基于ACI 209R(1992)模型进行了配筋和强度的修正,得到修正徐变系数预测模型。

Experiment on shrinkage and creep properties of six large size ultra-high strength reinforced concrete columns were carried out. According to the condition of force balance and deformation coordination between concrete and steel,the influence coefficient formula of reinforced concrete creep coefficient is derived.Based on the 209RACI(1992)creep model,the modified creep prediction model was proposed by introducing the influence coefficient of the strength correction factor and the reinforcement effect coefficient.