基于Hopkinson杆技术的混凝土动态压缩性能研究

Experimental Investigation on the Dynamic Compression Behaviour of Concrete Using Hopkinson Bar Technique

采用分离式Hopkinson压杆对混凝土试件(D=74mm)进行了动态压缩试验,得到了不同应变率下的混凝土动态抗压强度,研究了它的率敏感性,并得到了相应的临界应变率。结果表明:随着试件中应变率的增大,混凝土的动态抗压强度相应有不同比例的增加;同时在试验的基础上,分析了应变率对混凝土抗压强度的影响。抗压强度在相应的应变率超过一定值后会有一个较大比例的增加,抗压强度的临界应变率大约是40s-1。

In the present paper, experimental investigation on dynamic compression was car- ried out by using SHPB to get dynamic compression strengths under different strain state of con- crete（D=74 mm）, and the strain rate sensitivity on dynamic compression behaviour of concrete was studied. A critical strain rate was discovered. According to the experimental results, with the increase of strain rate of specimen, dynamic compression strengths increased in different ex- tent. On the basis of the experiment, the effects of strain rate on the compression strengths of concrete were analyzed. Compression strengths exhibited a critical strain rate, beyond which large increases in strength occurred. This critical strain rate was approximately 40 s^-1 for compression.