Workability And Mechanical Properties Study Of Fiber Reinforced Self-compacting Lightweight Concerete

Concrete is a kind of porous brittle material, with strong compressive strength but weak tensile strength and poor toughness. Those weaknesses have limited a further expanding application of concrete. In recent years, the research on fiber reinforced self-compacting concrete is attracting more attention. Fiber reinforced self-compacting concrete is a kind of new composite material with good performances and wide application. It can not only bring out the best features of each componant part, but also produce a kind of super feature beyond of each single componant. The object of this paper is a compound of the basalt fiber self-compacting light weight concrete and fibers and the consolidation aimed at combining the benefits of both of them and produce a kind of new concrete with better performance and stronger crack resistance, toughness and durability. Experimental investigation and analysis were carried out on the crack resistance, ductility, pore structure and microstructure of the fiber self-compacting light weight concrete and here are conclusions obtained:Firstly, theoretically analyzed how would fiber effect the performance of self-compacting light weight concrete and reached the relevance between the dosage of admixtures and fiber added in self-compacting light weight concrete, and proposed optimal mix design method of fiber self-compacting light weight concrete.Secondly, experimental investigation were carried out on the durability of fiber self-compacting light weight concrete, e.g. to test its impermeability by measuring water seepage height and chloride ion diffusion coefficient, to analyze its resistance to freezing and thawing based on the data from freezing and thawing circulate test.Thirdly, mercury porosimeter was adopted when testing the pore structure feature of fiber self-compacting light weight concrete. Data analysis focused on the effects of different aperture distribution and fiber addition.Finally, observed the interfaces of fiber self-compacting with scanning electron microscopy. There is no clear interfacial zone between fly ash ceramist and hardened cement paste and the trend of interface strengthening is clear. While, there is clear interfacial zone between fibers and hardened cement paste and some quantity of crystallized substance present in the zone.