| Title |
A Study on the Reliability of Combined Non-Destructive Testing Method for Strength Estimation of In-Situ Concrete |
| Abstract |
In the present study a series of experimental tests have been carried out to evaluate the reliability of combined non-destructive testing method for strength estimation of in-situ concrete. Main results may be summarized as follows: Concrete strength is greatly affected by curing environment and method -such as air curing and water curing-, as well as age of concrete. The present study particularly facuses on the effect of curing environment. Results show that the correlation coefficient and the determination coefficient of the ultrasonic pulse velocity and the rebound for solo method were 1.1% and 5%, respectively, and 6.7% for the combined method. Based on those results, therefore, it is recommended that the estimation equations of strength are better represented by the use of in-situ concrete. The following estimation equations are suggested.1)solo estimation equations;fc=k14.18R+65(R=0.623),fc=k268.6Vp-83(R=0.445)2)combined estimation equation;fc=k14.29R+k272.1Vp-219(R-sq=0.590) |