Applications of diffusion theory to permeability tests on concrete Part I: Depth of water penetration into concrete and coefficient of permeability

Abstract

Synopsis The paper describes an application of diffusion theory to the penetration of water under pressure into concrete. The resulting second-order differential equation is non-linear, because the water-storage capacity of the open pores in concrete depends upon the counterpressure arising. Numerical computer analysis of the permeability equation leads to a formula for calculating the coefficient of permeability when the values of the test parameters and the depth of water penetration are known. The application of the final formula to a series of laboratory test results shows that there is a fairly good correlation between the values of the coefficient of permeability so calculated and those based on direct measurement of water flow through a concrete specimen.