饱和混凝土有效模量及有效抗拉强度研究

Research on the effective modulus and tensile strength of saturated concrete

孔隙水的存在对混凝土的有效弹性模量及强度等力学性能产生很大的影响。采用三相球模型理论分析得到了饱和混凝土的有效体积模量与孔隙率之间的定量关系;不考虑孔隙水的抗剪能力,获得了饱和混凝土的有效弹性模量、泊松比与孔隙率的定量关系。基于最大拉应力准则,推导得到了饱和混凝土的有效抗拉强度及其峰值应变与孔隙率之间的关系。理论分析结果与Yaman等的试验结果吻合良好,表明本文方法能够用来预测饱和混凝土的有效弹性模量;与干燥混凝土相比,孔隙水的存在使得饱和混凝土弹性模量和有效抗拉强度均有所提高。

The existence of pore water has great influence on the mechanical properties of concrete, such as effective elastic modulus and strength, et al. Based on the three-phase sphere model, the quantitative relationship between the bulk modulus of saturated concrete and porosity was derived. The effective elastic modulus and Poisson＇s ratio of saturated wet concrete were deduced without considering the shear capacity of the pore water. According to the maximum tensile stress failure criterion, the quantitative relationship be- tween porosity and effective tensile strength and tensile peak-strain of saturated concrete were presented in this paper. Theoretical analysis results agree well with Yaman＇s experimental results, which demonstrate that the present method could be used to predict the elastic modulus of saturated concrete. Besides, it is found from the analysis results that the presence of pore water make the effective elastic modulus and ten- sile strength of saturated concrete improved compared with dry concrete.