Consideration on Application of Nondestructive Test to Estimate In-Situ Compressive Strength of Concrete: A Case Study

Abstract To comprehensively explore the utility of non-destructive tests (NDT) results for structural diagnosis, this study collected NDT results and core compressive strength test results from aged bridges. Girders and slabs were obtained from seven such bridges, and after sectioning, rebound hardness test (RHT) or ultrasonic pulse velocity test (UPVT) were conducted alongside coring. The standard equations for estimation in South Korea were applied and a comparison between core strength and strength estimated using NDT results was conducted. In addition, the relationship between the static modulus and core specimen strength was determined to assess the soundness of the concrete cores, a factor that influences NDT signals. Based on the experimental results, this study deliberates on the practical applications of NDT results in structural diagnosis. A protocol for calculating the characteristic in-situ compressive strength using NDT results without coring was proposed and statistically validate this protocol via a probabilistic simulation.