Title: A Method of Estimating the Mechanical Properties of Structural Concrete by Wash-Analysis of Samples in the Top Layer

Author(s): Makoto Kagaya, Hiroshi Tokuda, Makoto Kawakami, and Masami Shoya

Publication: Symposium Paper

Volume: 82

Issue:

Appears on pages(s): 731-744

Keywords: estimates; elasticity coarse aggregates; compressive strength; concretes; impact hammer tests; mechanical properties; modulus of nondestructive tests; samples; segregation.

DOI: 10.14359/6583

Date: 9/1/1984

Abstract:
The variation in the mechanical properties in the vertical direction can be assessed by the ratio of the difference between the measured value in top layer and that in the bottom layer over standard value obtained from cylinder concrete. The variation in internal composition can be estimated from that of unit coarse aggregate content. Good relationship existed between the degree of variation of unit coarse aggregate content in vertical direction and the ratio of unit aggregate content in the top layer to the specified value. Good relationship between the variation in the mechanical properties in vertical direction and that of internal composition represented by a ratio relative to the coarse aggregate content was also recognized. The variation in the degree of mechanical properties in the vertical direction could be assessed with good accuracy by measuring only the unit coarse aggregate content in the top layer. The simple and quick procedure developed in this work can be used to study the effect of segregation due to vibration-compaction on the mechanical properties in concrete structures and also to control the quality of concrete placed.