EVALUATION OF DURABILITY FOR CONCRETE IN TERMS OF WATERTIGHTNESS BY "PERMEABILITY COEFFICIENT TEST RESULTS". CONCRETE DURABILITY. KATHERINE AND BRYANT MATHER INTERNATIONL CONFERENCE, HELD AT ATLANTA, GEORGIA, USA, 27 APRIL-MAY 1987

The authors developed a new type of permeability testing apparatus which 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 structural concrete in terms of water-tightness. Effects of fluidity and mix proportion on the permeability was investigated on a concrete of typical specimen (disk and hollow disk types). Next, permeability coefficient 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 specimen which filled into the form sufficiently can be represented by an experimental equation. The durability of structural concrete can be evaluated from the water-tightness 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 above experimental equation. The authors understand that the permeability testing apparatus is sufficiently applicable to the structural concrete permeability test, and method to evaluate the durability of structural concrete using this apparatus is a ready available means which is capable of evaluating the durability of structural concrete in terms of water-tightness. (TRRL)