Title: Experimental Study on Fracture Behavior of Dam Concrete under Cyclic Loading

Author(s): Xudong Chen, Yuzhu Guo, and Shengtao Li

Publication: Structural Journal

Volume: 118

Issue: 2

Appears on pages(s): 193-202

Keywords: acoustic emission; dam concrete; dynamic load; fracture mechanism

Date: 3/1/2021

Abstract:
To study the fracture behavior of dam concrete subjected to elevated-amplitude cyclic loading, the three-point bending test was carried out. During the loading process, the internal acoustic emission (AE) signal and surface cracks of dam concrete beams under cyclic loading were recorded using three-dimensional digital image correlation (3-D DIC) technique. The results show that with the increase of loading rate, AE events are concentrated near the peak load. There is a safe range of the historical index and signal intensity before failure of concrete. The analysis of load-crack mouth opening displacement (CMOD) curves shows a rate effect on the stiffness attenuation. In addition, the crack propagation mechanism under different load rates and the relationship between crack tip opening displacement (CTOD) and CMOD under different elevated-amplitudes of load are analyzed.