Orthogonal Experiment Study on Mechanical Properties of Hybrid Fibre Reinforced Shale Ceramisite Concrete

Abstract

The slump, cube compressive strength and splitting tensile strength tests of 9 groups of hybrid fiber reinforced shale ceramisite concrete (HFSC) and 1 group of C30 reference concrete were conducted by orthogonal experimental method. The effects of shale ceramisite volume replacement, basalt fiber volume fraction and polypropylene fiber volume fraction on the mechanical properties of HFSC were investigated. The results show that the splitting tensile strength and tension-compression ratio of concrete can be significantly improved by adding fiber, which plays a positive hybrid effect. The maximum increase in the tensile strength of concrete by basalt fiber and polypropylene fiber is 57.33% and 58.19% respectively, while the influence of compressive strength was small. Shale ceramisite significantly reduces the compressive and tensile strength of concrete. When the replacement increases from 0% to 15%, the compressive strength of HFSC decreases by 19.98%, while the tensile strength has underwent an iterative process of increasing and decreasing due to the fiber reinforcement effect. All three factors reduced the slump of concrete mixture. The shale ceramisite and basalt fiber have significant influence, and polypropylene fiber has a greater impact. The influence mechanism of three factors on mechanical properties of HFSC was revealed.The prediction models of cube compressive strength and splitting tensile strength of HFSC were obtained, and the accuracy of model is high.

Keywords

• basalt fiber
• mechanical properties
• orthogonal experiment
• polypropylene fiber
• shale ceramisite concrete
• strength prediction model