ABSTRACT
The surface layer of concrete has a barrier performance for penetration of some substances into concrete, it is important to examine the quality of surface concrete and the influence of its characteristics on hardened concrete. It is well known that the fragile layer of concrete surface is formed due to bleeding. The fragile layer of concrete surface indicates lower strength and resistance of penetration of some substances compared with internal part of concrete, and it is thought that its thickness affects the durability of concrete. The fragile layer of concrete surface is not only formed at upper part of mold but also formed at side part of mold. And it is thought that the thickness of fragile layer of concrete surface at side part of mold vary with the member thickness. The objective of this study is to examine the influence of fragile layer on some properties of hardened concrete.
