Experimental Research On Carbonation Of Steel Fiber Reinforced Lightweight Aggregate Concrete

Steel fiber reinforced lightweight aggregate concrete is a kind of new matrix composites based on lightweight aggregate concrete, have excellent physical and mechanical properties, greatly improved and enhanced the performance of lightweight aggregate concrete, the traditional sense of the concrete material Innovation is a warrant on the promotion of new technologies. Since steel fiber lightweight aggregate concrete, the domestic and foreign scholars on the SFRLC basic mechanical properties of more research on the durability study is relatively small.In this paper's carbonization experiment, the volume fraction of steel fiber and carbonization time are taken as variable parameters. Through the carbonization experiment of 162 concrete specimens with the size of 100mm×100mm×100mm and 93 concrete specimens with the size of 100 mm×100mm×400mm, the basic mechanic properties before carbonization and after carbonization, such as compressive strength, splitting strength and flexural strength of concrete, of steel fiber reinforced concrete are measured, and also carbonization depth at every defined carbonization time. At the same time, the whole failure process and the failure mode of steel fiber reinforced concrete are surveyed. The reinforced mechanism of the steel fiber is studied, and the effects of the volume fraction of steel fiber, the grade of concrete intensity, carbonization time on the basic mechanic property and carbonization depth are analyzed. At last, two experiment empirical formulas about indoor and natural environmental carbonization depth have been put forward, and steel fiber reinforced lightweight aggregate concrete's cover thickness have been discussed according to carbonization depth.Test results show that: (1)Lightweight aggregate concrete, steel fiber incorporation appropriate, its ability to significantly enhance anti-carbonation, mechanical properties have markedly improved, and Central breaking into shape by a certain brittle plastic, the paper proposed steel fiber Volume 1% more appropriate. (2) Lightweight aggregate concrete steel fibers in the indoor humidity in the environment minimum thickness values can be protected in accordance with the ordinary concrete to determine. (3) Steel fiber lightweight aggregate concrete block after carbonation of compressive strength and tensile strength than that of carbonated increased slightly, bending strength than that of carbonated declined slightly.The experimental results can provide experimental and theoretical basis to designing durability of the SFRLC, and can promote the expansion and the application in engineering of SFRLC technology, and provided for reference to research and engineering application in the future.