Title:
Evaluation of Durability for Concrete in Terms of Watertightness by "Permeability Coefficient Test Results"
Author(s):
Isamu Tanahashi
Publication:
Symposium Paper
Volume:
100
Issue:
Appears on pages(s):
187-206
Keywords:
concrete durability; evaluation; measuring instruments; penetration tests; permeability; General
DOI:
10.14359/3558
Date:
4/1/1987
Abstract:
A new type of permeability testing apparatus has been developed that is capable of direct measurement of the permeability coefficient of structural concrete for the purpose of establishing a new method to evaluate the quality and durability of structure concrete in terms of watertightness. Effects of fluidity and mix proportion on the permeability was investigated on typical concrete specimens (disk and hollow disk types). Next, permeability coefficients of structural concrete (wall and floor) were investigated and evaluation of concrete durability was carried out. From these experiments, the following conclusion was obtained: The permeability coefficient of typical specimens that filled into the form sufficiently can be represented by an experimental equation: Wa = a(w/c - b)c - d/(Ww - e) + f. The durability of concrete can be evaluated from the watertightness, which is derived from comparison of measured permeability coefficient and the theoretical permeability coefficient obtained by substituting the water-cement ratio and unit water quantity of designed mix proportion into the previously given formula. The authors understand that the permeability testing apparatus is sufficiently applicable to the structural concrete permeability test and the method of evaluating the durability of structural concrete using this apparatus is capable of evaluating the durability of structural concrete in terms of watertightness.