The backbone of modern infrastructure is concrete, yet modern ultrasonic characterization techniques often fail to be accurate and repeatable. Recent advances in low frequency ultrasonic array hardware have generated a new potential for improved material and structural characterization of concrete. However, the analysis and interpretation associated with the new array based hardware is more difficult than previous ultrasonic concrete applications. In this paper we present three data analysis algorithm modifications and experimentally validate each modification for improvement over the existing commercial algorithms. Validation of each modification occurs in full scale in-service samples. After validation in this paper we present a commercially analyzed inconclusive inspection of a bridge deck, with applying the modified algorithms the results are improved and a conclusion can be safely reached.