Abstract:
We study the impact of using different rubber powder volume to replace the amount of sand on the deformation amount of sprayed concrete compressive strength, flexural strength, splitting tensile strength and fracture, and analyze the causes and mechanisms of these effects. Studies have shown that 28 d compressive strength of shotcrete replaced has a certain degree of improvement when the rubber powder sand does not exceed 10%, and the compressive strength of each age shows a downward trend when rubber powder sand exceeds 10%. Flexural strength increases with the amount of rubber powder to replace sand after the first increases and then decreases; splitting tensile strength increases when the amount of silt in the rubber does not exceed 10%, little changes at 10% to 15%, decreases more than 15%; the amount of concrete in disguise increases slightly when the rubber powder sand content is replaced by an equal volume of not more than 15%, and declines when the content exceeds 15%; suitable rubber powder content is substituted with an equal volume of 5% to 10% of the amount of sand. Reason for improving the performance of rubber powder sprayed concrete is to make mixing rubber powder sprayed concrete form by the fracture toughness of brittle fracture transition to fracture.