混凝土损伤参数的截面积效应试验研究

Experimental Study on Size Effect of Damage Parameters of Concrete

针对直接测量损伤目前难度较大的问题,提出采用加引气剂模拟损伤的方法,利用所加不同比例引气剂模拟不同程度的损伤,并对不同尺寸混凝土试件做了单轴压缩试验,测定了相应的弹性模量,并计算出混凝土的初始损伤D0和损伤阈值Df,得到了损伤参数随试件截面积的变化规律,即损伤参数值随试件截面积的增大而增大,但增幅逐渐减小。

Aiming at the problem of direct measure damage, this paper puts forward a test to simulate the damage by adding air entrain admixture （AEA） into concrete specimens. By using different proportion of AEA to simulate the dam- age of different degrees, the uniaxial compression test is conducted on concrete of different sizes with the result of corresponding elastic modulus. At the same time, it calculates initial damage Do and damage threshold Df, Finally, the test obtains the regular pattern of damage parameter with test specimen of different section areas, that is, the damage parameter increases with increasing section area of the test specimen while the increasing rate decreases gradually.