### Improvement method of compression test and the dynamic damage of concrete

LI Ming, ZHU Zhaoquan, LIU Lin*

1. College of Civil and Transportation Engineering, Hohai University, Nanjing 210098, Jiangsu, China
• Received:2016-03-28 Online:2017-02-20 Published:2016-03-28

Abstract: In order to explore the incident waveform improvement method in concrete dynamic compression test thus further exploring the dynamic damage and the mechanical property of concrete under the impact loading, the experiment adopted the conventional large diameter split Hopkinson pressure bar(SHPB)to study the dynamic compression test of concrete. The dispersion effect of the incident pulse and the serious high frequency oscillation phenomenon causes large errors in the result of the experiment, but it is the key to ensure the validity of the test and the reliability of the test results to ensure the uniform distribution of stress and to maintain the constant strain rate loading before the test piece destroyed. This study used the brass shaper technology to improve the incident wave to reduce the experimental error and then by controlling variable, then used the method of the combination of theoretical formula and experimental, further researched on the influence of air pressure and impact times on the dynamic damage of concrete. It was concluded that the shaper made of small diameter solid copper thin could improve the accuracy. The damage degree of concrete was gradually augmented with the increase of the repeated impact times the dynamic elastic modulus was decreased, and the ability to resist impact was attenuated.

CLC Number:

• TU112.3