Influence of Calcium Leaching on Young's Modulus and Flexural Strength of Hardened Cement Paste

Abstract

Up to the present, many studies on calcium leaching have focused on ultra-long-term durability. On the other hand, it has been pointed out that aqueous solutions of chlorides such as anti-freezing agents that are sprayed on road structures in cold regions promote calcium leaching, and the author has confirmed this fact experimentally. NaCl, CaCl₂, etc. are sprayed on roads as anti-freezing agents, and their usage has been increasing rapidly since the 1990s. Therefore, it is important to investigate the effect of calcium leaching on the mechanical properties of concrete. In this study, the Young's modulus of hardened cement paste specimens with calcium leaching was determined by bending tests. After the bending test, the calcium concentration distribution on the cross section of the specimen was investigated by EPMA. Based on these results, the relationship between the decrease in calcium concentration and Young's modulus in hardened cement paste was formulated as a power function.