Ultrasonic Technique for the In-Situ Monitoring of the Setting, Hardening, and Strength Gain of Concrete

摘要

The nondestructive, in-situ testing of early-age concrete properties is a crucial tool for monitoring the progress of many construction projects in the building sector. The application of such techniques can establish the earliest possible form removal from concrete construction elements, thereby opening highways to traffic, releasing prestress from steel reinforcement, or applying post-tensioning with greatest efficiency. A nondestructive, ultrasonic technique, which measures the reflection loss of ultrasonic shear wave reflections from the concrete surface, was developed at the Center for Advanced Cement-Based Materials(ACBM). The focus of this research project is to develop a nondestructive field sensor for in-situ monitoring of the setting, hardening, and strength gain of cementitious materials. The research here will immediately tie in with the results of the previous funding period. Special attention will be given to determining the need of the test method to be calibrated for different mix designs. It is our aim to merge the results of experimental studies and numerical modeling to create a model for predicting early-age concrete properties from in-situ wave reflection measurements.