Influence of interfacial strength of reinforced concrete beams under dynamic loading

LIU Hao 1, , ZHANG Yafang , and ZHANG Kai 2 1) Shenzhen Municipal Design & Research Institute Co. Ltd. , Shenzhen 518029, Guangdong Province, P. R. China 2) School of Civil Engineering, Guangzhou University, Guangzhou 510006, Guangdong Province, P. R. China Abstract: In order to study the effects of interfacial changes on the mechanical properties of concrete beams under dynamic loading, the dynamic responses of the beams under different interface strengths have been simulated in this paper, by using a finite element program RFPA3D-Dynamic. With considerations of material non-uniformity, the crack development and damage patterns of the beams, and the peak load curves and accumulated acoustic emission curves have been analyzed. The results show that the crack expansion patterns at different interface strengths vary significantly, and when the interface strength is small, the specimens mainly undergo bending tensile damage. Furthermore, as the interface strength increases, the damage pattern gradually changes to shear damage dominated by oblique cracks. The peak load of the specimen increases gradually with the increase of the interface strength, and tends to level off when it approaches the concrete strength. The accumulative acoustic emission energy shows a law of increasing first and then decreasing with the increase of the interface strength.