Effect of seawater dry-wet cycling on the durability of concrete repair materials

Abstract

In order to investigate the durability of concrete repair materials in marine environments, this research selected four typical repair materials commonly used on the market to carry out indoor seawater dry and wet cycling tests and real marine environment exposure tests. The research results show that: the compressive strength and abrasion loss variations of these four repair materials under indoor seawater dry-wet cycling are closely related. Among them, magnesium phosphate mortar demonstrates better resistance to seawater erosion in both environments. The chloride ion penetration depth of four repair materials increases with seawater dry and wet cycling time. Its law of change is closely related to the law of change of the most probable pore size inside the material, while the epoxy resin mortar and acrylic-modified mortar have a high depth of chloride ion penetration under the real marine environment due to the microcracks and porous phenomena appearing on the surface of the material. In addition, the results of the tests in the real marine environment differed somewhat from those in the indoor environment, highlighting the need to conduct real marine environment tests. The results provide theoretical support for selecting and evaluating concrete repair materials in the marine environment.