Evaluation of basic performance of concrete using a penetrating water repellency based on cement reactive siloxane polymer

Abstract

This study is a part of research on the development of cement reactive siloxane polymer-based penetrating water repellent, and its goal is to perform basic performance evaluation of the concrete, to which the penetrating water repellent was applied. To this end, reactive urethane prepolymer that coats micro-pores of concrete was fabricated based on the polysiloxane, and oil-based and water-based penetrating water repellents, UP-40 and UP-50C, respectively, were fabricated by controlling the molecule size and modifying the surface. Concrete specimens of three compressive strengths (18 MPa, 24 MPa, 30 MPa) were fabricated, and the depth of penetration was measured according to the application method of penetrating water repellent (brush, immersion, and spray methods), and the compressive strength, water absorption resistance, and water permeability resistance were evaluated for the penetrating-water-repellent-applied concretes. In the results, the depth of penetration of penetrating water repellents was in the range of 2.7-9.2 mm according to the strength of concrete and application method, and the evaluation revealed that as the compressive strength of specimen increased, the penetration performance penetrating water repellent decreased. Furthermore, when the penetrating water repellent was applied, there was very little change in the compressive strength while excellent water absorption resistance and water permeability resistance were demonstrated.