含初始缺陷混凝土的拉伸试验研究

Study Impact on Tensile Properities of Concrete with Different Initial Defections

在相同配合比下的混凝土试件中加入4种不同含量的引气剂,用来模拟混凝土试件的初始缺陷程度,并在WAW-E2000万能试验机上进行混凝土试件的轴向拉伸试验,测出了混凝土在拉伸试验过程中的应力-应变全曲线,研究了不同含量的引气剂对混凝土的抗拉强度、变形特性与损伤特性的影响.试验结果表明:随着引气剂含量的增大,混凝土的应力-应变曲线逐渐变平缓,混凝土内的初始损伤程度相应增加,且抗拉强度随之降低,而峰值应变基本保持不变.

Initial defections were simulated through mixing different quantities of air entraining agent into four test samples of the same concrete,and then tensile tests of plain concrete specimens were carried out by using a static-dynamic test machine. The relation of stress-strain curves of the concrete were obtained,and the effects of different initial defections on tensile strengths,stress-strain curves and damage behaviors of the concrete were investigated. It is found that the initial damage of concrete are increasing,and the stress-strain curves are began to flatten. The bending strengths of the concrete are decreased with the increasing quantities of air entraining agent,but the peak strains are remained unchanged.