DEVELOPMENT AND APPLICATION OF RAPID TEST METHODS
FOR ASSESSING THE TIGHTNESS OF COVER CONCRETE
29th Our World in Concrete and Structures (OWICs) - 2004
M. Shoya*, Hachinohe Institute of Technology, Japan
Pressure diffusion theory, Murata's input method, Air tightness, indoor test, in-situ test, rapid
air permeability, rapid water permeability, water tightness
The rapid water permeability test for the surface layers of concrete developed by authors, was introduced taking into consideration the pressure diffusion theory. Then, three different specific in-situ tests to assess the tightness of the surface layers of concrete, such as rapid air permeability test, the water absorption test applying Figg's method and authors' rapid water permeability test, were examined.
In the experiments, specific parameters obtained in three in-situ tests corresponded well to air permeability coefficient and coefficient of water diffusion in the firms indoor tests, and those parameters satisfactorily reflect the change in the tightness of the surface layer caused by the water to cement ratio, age of test and cement type. In addition, those parameters also sensitively reflected the change of the permeability due to the existence of the model crack. In conclusion, three test methods are promising for providing air tightness or water tightness of the surface layer of concrete from the view points of the use of simple testing devices and convenient procedures.