Research on the Durability of RPC Mixed with Different Types of Fibers under Salt Freezing

Gengchen Wu, Xia Yang, Zhenhao Mao

School of Urban Construction, Yangtze University, Jingzhou, 434023, China

Abstract: This paper aimed to study the coupling effects of different fibers (steel-polypropylene hybrid fibers, steel-polyvinyl alcohol hybrid fibers, steel-polyvinyl alcohol- polypropylene hybrid fibers) and their contents on the salt frost resistance of RPC. The weight loss relative dynamic elastic modulus and splitting tensile strength of RPC were investigated. Results indicated that the increase of polypropylene fibers dosage played-negative roles in the durability index of RPC specimens. With the increase of polyvinyl alcohol fibers content, the durability index of RPC specimens decreased first and then increased. The threshold values of polyvinyl alcohol fibers and Polypropylene fibers were 1% and 0.3%.Finally, adding two kinds of fibers at the same time can effectively improve the spatial structure of RPC, produce positive hybrid effect, and greatly improve the salt frost resistance of RPC.

Keywords: RPC; NaCl freeze–thaw cycles; Mass loss; Splitting tension; Relative dynamic modulus