Title: Study on Watertightness of Concrete

Author(s): Jiro Murata, Yoshio Ogihara, Shigeo Koshikawa, and Yoshinari Itoh

Publication: Materials Journal

Volume: 101

Issue: 2

Appears on pages(s): 107-116

Keywords: flow; pressure; water.

DOI: 10.14359/13046

Date: 3/1/2004

Abstract:
The watertightness of concrete is judged by the depth of penetration of water forced in under pressure with the mechanism of flow of seepage water examined theoretically and experimentally. As a result, it is found that in the case of low water pressure approximately 0.15 MPa or less, the flow is Darcy seepage flow, the same as flow in an ordinary sand stratum, whereas in the case of high water pressure, the flow is diffused seepage flow accompanied by internal deformation of concrete. It is suggested that the watertightness of concrete be evaluated by seepage coefficient in the case of the former and diffusion coefficient in case of the latter. The effects of various chemical admixtures on the watertightness of concrete are discussed based on the aforementioned research results, while a sectional design method for watertight concrete members is proposed, with important data provided on both.