Abstract
To explain the mechanisms of the deterioration of fiber-reinforced concrete caused by freezing and thawing, observation has been made with such experimentals as: (1) Metrology of dynamic modulus of elasticity. (2) Rigidity flexural strength tests. (3) Measurements of pore structure distribution. (4) SEM observation. As a result of the attempt, the following has been made clear.
With the concrete reinforced with glass, aramid and PVA fiber, freezing and thawing are liable to give rise to cracks in the matrix concrete, resulting in inferiority in rigidity. Despite the above, none of drastic lowering of flexural strength is to be seen, which might be derived from the reason that fibers play a role of bridging the cracks. On the other hand, generation of cracks in the matrix owing to freezing and thawing seldom occur with the steel-fiber reinforced concrete. Furthermore lowering in bending strength or rigidity is hardly caused.
