Strength Experiment and Mechanism Analysis of Cement Mortar with Sticky Rice Pulp

Abstract

Cement mortar with sticky rice pulp is an innovative composite material. Investigating its mechanical properties and strength mechanism is essential for the future engineering application. Taking the pulp concentration and the mortar ages as the variables, we tested five groups of blocks for the compressive strength and flexural strength, and observed their microstructures with a scanning electronic microscope. The results indicated that the microstructure got dense if the added pulp had a concentration of about 0.3%, and thereby its flexural strength would significantly improve, while the hydration products agglomerated and the microstructure got loose if the added pulp had a concentration of more than 1.0%, which caused a substantial decline in flexural strength. Besides, the hydration reaction was hindered at the early stage due to the addition of the pulp; hence the early strength of the mortar is on the low side. According to the strength mechanism analysis, all the results are mainly attributed to the effects: "water-reduction", agglomeration and retarding, caused by the addition of the pulp.