2.モルタル中を伝わる衝撃音波の速度とモルタルの品質(その2) : 衝撃波音速測定法によるコンクリートの無破壊試験の研究・その3

Abstract

This paper is the continuation of Part 1 written by the same author in Transactions of A.I.J., No. 52, Oct. 1955. In the preceding paper the relations between the extent to which the sound velocity depends upon the quality of mortar and its compressive strength, and both dynamic and static modulus of elasticity, are described. Results of tests and conclusions found in this paper may be briefly summarized as follows: (1) The variations of sound velocity are observed to depend largely on the water cement ratio. However, the mixing proportion with a higher fine aggregate content results the higher velocity and the higher dynamic modulus of elasticity at the same water cement ratio, whereas the quantity of fine aggregate has no influence on the compressive strength and the static modulus of elasticity. (2) There is no definite relation between the size of fine aggregate, the sound velocity, both dynamic and static modulus of elasticity, and the compressive strength. (3) When the amount of entrained air agent is increased under constant absolute volume of total water and air void, it has been found that the amount of air void has no appreciable effect on the sound velocity, whereas the compressive strength of water-cured specimens increases with increasing amount of air void.