Estimation Method of Washout Resistance Performance of Materials for Repair of Water-leakage Crack in Underground Concrete Structures

摘要

Concrete structures are cracked due to various behavioralenvironments effects (drying shrinkage, temperature difference,etc.) and repairing materials are used to repair these cracks bythe method of injection.ISO TS 16774, which was established in July 2016 as astandard for the quality control of the repair materials, includestest methods for repair materials for the water-leakage cracks inconcrete structures. Part 3 of this specification, Test Method forWashout Resistance, analyzes the resistance performance ofleakage repair material against abrasion from groundwater flow.This specification reflects the field conditions where variousmechanisms of leakage repair material should be applied afterfilling a certain amount of repair material in a plastic plate. Thetesting is conventionally done by covering the specimen withnonwoven fabric.A constant water flow rate of 0.2 m/s (derived from annexsection of the test specification, KS F 4935) is applied to thewaterproofing material, and the difference of the washout massdue to erosion is recorded. It is considered appropriate to verifythe resistance performance of the repairing material whichshould be applied to the cracked region directly in the actual siteand to exhibit the flow rate of the flow rate, rather thanindirectly measuring the loss amount using the nonwoven fabric.In this study, we evaluate the flow resistance performancewithout using nonwoven fabric and compare it with the existingtest method.