Accuracy of Estimating Compressive Strength of Deteriorated Concrete Seawall by Nondestructive Evaluation (NDE)

摘要

A condition evaluation conducted on a concrete seawall using: (a) limited destructive evaluation, and (b) extensive nondestructive evaluation (NDE) measurements demonstrated the effectiveness of the combination method (CM). The CM was used in conjunction with correlation curves and permitted the estimation of the compressive strength (CS) of the concrete from NDE measurements in locations where no coring was performed. In this study, correlation curves related the CS to two different NDE properties: ultrasonic pulse velocity (UPV) and Schmidt rebound hammer number (RN). The study demonstrated that the CS could be estimated with the UPV property to within 20 percent of its actual value by using the CM to develop correlation curves of RN versus CS and UPV versus CS. The study discusses the circumstances where the CM can be useful and where NDE measurements alone are sufficient for a complete evaluation. This investigation also sought to determine the critical parameters that will permit Government and industry to make a limited transition - technology does not permit a complete break at this time-from destructive diagnostic methods to NDE. In addition, the report provides useful information on the successes, pitfalls, and problems encountered in applying NDE to practical field situations.