冻融循环下砼力学性能与相对动弹性模量关系

Relationship between mechanical properties and relative dynamic elasticity modulus of concrete after freeze-thaw cycles

研究冻融循环作用后混凝土受拉峰值应力、受压峰值应力、受拉峰值应变、受压峰值应变、受压极限应变及受拉初始弹性模量与相对动弹性模量之间的关系.对经过0,25,50,75,100和125次冻融循环作用的C20,C30,C40和C50抗拉试件进行单轴拉伸试验,对经过0,25,50和75次冻融循环作用的C20棱柱体试件进行抗压试验,得出各力学性能随相对动弹性模量变化的规律,回归得出相关的计算公式.结果表明:冻融循环作用后,随着相对动弹性模量的降低,混凝土的受拉峰值应力、受压峰值应力及受拉峰值应变等力学性能指标逐渐减小,而受压峰值应变及受压极限应变却逐渐增大.

Relationships between relative dynamic elasticity modulus and concrete mechanical properties of peak tensile stress,peak compressive stress,peak tensile strain,peak compressive strain,ultimate compressive strain and initial tensile elastic modulus were investigated after freeze-thaw cycles.Samples of C20,C30,C40 and C50,undergone 0,25,50,75,100 and 125 freeze-thaw cycles,were subjected to uniaxial tensile experiments.Samples of C20,undergone 0,25,50 and 75 freeze-thaw cycles,were subjected to compressive experiments.Based on the test results,calculation formulas were obtained by regression.The results show that as relative dynamic elasticity modulus reduces,peak tensile stress,peak compressive stress and peak tensile strain decrease gradually,while peak compressive strain and ultimate compressive strain increase gradually.