Experimental study on stress-strain relationship of high strength coral concrete (HSCC)

In recent decades, with the advancement of coral reef construction, the inception of design and production of coral concrete has emerged. However, current research primarily focuses on medium and low strength grades, leaving the exploration of high-strength coral concrete (HSCC) in its infancy. Therefore, in this paper, uniaxial compression test and microscopic mean are utilized to investigate the stress-strain full curves, crack development and damage characteristics of HSCC with different strength grades and fiber. The findings demonstrate that after the peak stress, the stress of HSCC with different strength grades decreases sharply, and their residual stresses are 21.5%-30.3% of the peak stress, which is lower than that of ordinary coral concrete, which is 29.2%-52.5%. The crack inclination angle theta of high-strength coral concrete containing fiber is mainly concentrated at 62 degrees-70 degrees, and it shows ductile damage. Moreover, fiber in high-strength coral concrete undergoes damage mainly by pulling and breaking. Additionally, the locations of the characteristic points of the stress-strain curves of HSCC are significantly different from those of ordinary concrete and lightweight aggregate concrete, and the constitutive equation proposed in the paper effectively reflect the variation of the stress-strain curves of HSCC.