Investigation on the relationship between flexuralstrength, flexural toughness and impact toughnessof styrene–butadiene rubber latex-modifiedcement concrete

摘要

The flexural strength, flexural toughness and impact toughness of styrene–butadiene rubberlatex-modified cement concrete are studied in this study. In order to reveal the mechanism, themicrostructure and pore size distribution are researched by means of scanning electronmicroscope and mercury intrusion porosimetry. The results show that the flexural strength,flexural toughness and impact toughness all first increase and then decrease whenpolymer–cement ratio increases from 0 to 60%, but the optimum value of correspondingpolymer–cement ratio is different. The flexural toughness and impact toughness have nosignificant relations to the flexural strength, but there are roughly linear relationships between theflexural toughness and impact toughness. Scanning electron microscope and mercury intrusionporosimetry show that the proper addition of polymer can make the concrete denser, thedeviation of flexural toughness and impact toughness decrease, but the flexural toughness islower, and it can characterise the toughness of polymer-modified cement concrete with moreaccuracy.