Abstract
Mortar and concrete are the porous material which contains many gaps inside, and there are many cases that the action of water influences durability. So, various experiments were done by this research to grasp foundation performance about water solvent type and addition type of silicone water–repellent agent which fear to the environment influence due to the volatilization and the melt is rare and can be expected to give water–repellent effect in the simple method on the surface of the concrete. Excellent effect on repression of water absorption by using the silicone oil of the addition type can be given, and the durability improvement of the mortar and the concrete in the PC product can be expected by the addition of the silicone oil. And a subject is still left to use water solvent type of water–repellent agent in case of the repair and improvement of the existent building because it is inferior to the organic solvent type of water–repellent agent with repression performance of water absorption.
