Experimental and numerical investigations on the mechanical properties of coral aggregate seawater concrete

Abstract

To study the mechanical properties of coral aggregate seawater concrete (CASC), a combination of experiments and numerical simulations based on the HJC and K&C models was used, the failure mode and cube compressive/axial compressive/splitting tensile strength (f_cu, f_c, f_sp), complete stress–strain curve of CASC with different strength grades (C30 ∼ C55) and cement types (Portland cement, Basic magnesium sulfate cement) was studied, and the differences in the mechanical properties of CASC with lightweight aggregate concrete and ordinary aggregate concrete was revealed. The results show that: cube/prismatic/splitting tensile specimens of CASC mainly suffer from quadrangular cone damage/oblique damage/central cracking damage, respectively. BMSC can significantly reduce the brittleness and increase the ductility of CASC. A significant linear relationship between f_cu and f_c, f_sp for C30 ∼ C50 CASC was found and the corresponding transformations was established. The numerical model suitable for researching the mechanical properties of CASC was proposed, the errors between simulated and measured values of f_cu, f_c and f_sp of C30 ∼ C50 CASC were 2.5 % ∼ 3.1 %, 4.4 % ∼ 5.7 % and 2.7 % ∼ 4.4 %, respectively. Considering the characteristics of high brittleness of CASC, a more suitable stress–strain curve model is proposed, the accuracy can be improved by 1.6 % ∼ 5.9 %.