HIGH ACCURACY PAVEMENT THICKNESS MEASUREMENT USING GROUND PENETRATING RADAR (NONDESTRUCTIVE TESTING FOR QUALITY CONTROL OF NEW PAVEMENT)

Ground Penetrating Radar (GPR) interpretation technology developed through the Strategic Highway Research Program (SHRP) was used to nondestructively determine pavement thickness on new pavements. The new pavements were bid per square yard (SY) of pavement surface area as either portland cement concrete pavement (PCCP) or full depth asphaltic concrete (AC). Since bid per SY, the pavements must meet Missouri specifications requiring the pavement to be no more than 0.2 in. thin of the plan depth. Missouri Department of Transportation (MoDOT) contracted with Pavement Systems Engineering and INFRASENSE Inc. to obtain and compare GPR data on the pavement thickness with the cores commonly taken for quality control and assurance by MoDOT. It was believed that GPR with good interpretation software and employing some special techniques could be capable of measuring to the 0.2 in. tolerance needed and in the future replace current coring practices (destructive testing) with GPR testing (nondestructive).