Mechanical properties and uniaxial constitutive model of fiber-reinforced coral aggregate concrete

This article studied the mechanical properties and constitutive model of fiber-reinforced coral aggregate concrete (FRCAC). The test results show that basalt fibers, carbon fibers, and polypropylene fibers (BFs, CFs, and PFs) can enhance the cube compressive strength and splitting tensile strength of coral aggregate concrete (CAC), but there are optimum contents. The optimal content of BFs, CFs, and PFs are 0.8%, 1.5%, and 0.3%, respectively. Fibers increase slightly the elastic modulus of FRCAC. The peak stress, peak strain, and ultimate strain of CAC can be improved by fibers, and the improvement effect is CFs, BFs, and PFs in descending order. According to the experimental results, a damage constitutive model suitable for FRCAC was proposed, which can efficiently indicate the stress-strain relationship of FRCAC. The damage parameter in the model can predict the damage evolution process of FRCAC.