Effect of Hollow Body Material on Mechanical Properties of Bubble Concrete

The bubble concrete (BC) produced by mixing high-strength hollow bodies into concrete has been proven to be effective in reducing density while maintaining strength. It has been verified that the position distribution of hollow bodies inside hardened BC significantly affects the compressive strength of the BC. However, the effect of hollow body material on the strength of BC has not yet been established. In the present paper, through concrete compression experiments and the nonlinear finite element analysis (F.E.A.), a comparative study of BC with three different hollow bodies—steel spheres, sand bonded stainless steel spheres, and ceramic spheres—has been carried out. The results show that the difference in elastic modulus of hollow bodies and concrete is the primary reason for the inhomogeneous stress distribution inside the concrete. The interface between the hollow body and hardened concrete could be increased using epoxy resin, thus enhancing the compressive strength of BC specimens by 26.6% compared to control concrete. The ceramic material is tightly integrated with the concrete, but as a brittle material, the ceramic cannot sustain colossal stress and subsequently breaks down.