Modification of rubber particles and its application in rubberized concrete

Using rubber particles (RP) to replace part of fine aggregates in concrete can reduce freezing damage in cold climate areas, and can also reuse waste tire rubber to reduce black pollution. However, the addition of RP will reduce the compressive strength of concrete, one of the reasons is poor bonding strength of the interface between RP and concrete, which further affects the various properties of concrete. In this study, based on seed coating technology, silica powder and water glass were used as the main materials of the coating layer (Coat) to coat and modify the RP. Then a series of simulation tests and mechanical strength tests were carried out on the coated modified RP (CRP) to verify the stability of the CRP. At the same time, specimens of concrete bricks doped with CRP were prepared, and a series of mechanical performance tests and frost resistance tests were carried out. The final test results show that the compressive strength of the prepared concrete brick doped with CRP can reach more than 40 MPa at 28 days. The number of freeze-thaw cycles exceeds 100 times, and the compressive strength at 100 freeze-thaw cycles is 38.1 MPa, whose loss rate is 13.8%. The above results show the feasibility of the coating modification method proposed in this paper, and provide a new solution for the preparation of frost resistant rubberized concrete in the future.

Automated summary

Using rubber particles as a replacement for fine aggregates in concrete can reduce freezing damage and black pollution. However, this addition decreases the compressive strength of concrete due to poor bonding strength between the rubber particles and concrete. This study proposes a coating modification method using silica powder and water glass to improve the stability of the rubber particles. The results show that the prepared concrete bricks with coated modified rubber particles have high compressive strength and good frost resistance.