Evaluation of Pore Size Distribution for Controlled Permeability Formwork Liner

Controlled permeability formwork liner (CPFL) is the functional material similar to nonwoven fabrics and its filtration and drainage performance is dominated by the pore size distribution (PSD) of matrix. In this paper, suction table method, generally used to measure soil pore diameter, is improved for testing PSD of CPFL and experimental data was compared to the results from four other normal experimental methods, i.e., wet sieving method, bubble point method, mercury intrusion porosimetry (MIP) method and image analysis. The comparison indicates that PSD of CPFL obtained from suction table show good accuracy and repeatability. Furthermore, a modified mathematical model derived from Rawal model and Fature model is proved to be suitable for determinating PSD of the matrix of CPFLwith bilayer structure, and have a good agreement with the experimental data from suction table.