692199993

Final report; July 1, 2003-June 30, 2005.

NTL-HIGHWAY/ROAD TRANSPORTATION-Materials ; NTL-HIGHWAY/ROAD TRANSPORTATION-Pavement Management and Performance ;

The North Carolina Department of Transportation has used traditionally flexural strength tests for acceptance testing of Portland cement concrete pavements. This report summarizes a research project implemented to investigate the feasibility of using other strength tests and nondestructive tests, to accomplish the same objective of ensuring an adequate modulus of rupture of the slab but avoiding or reducing the need to perform a large number of flexural strength determinations for acceptance testing. The present work has been laid around using a nondestructive test (a resonant column) to measure a seismic modulus that is used as a rating tool to evaluate the repeatability of duplicate specimens before the specimens are strength tested. This has been accomplished by developing regression lines and confidence and prediction intervals for the correlation of the seismic modulus to flexural, splitting tension, and compressive strength test. All these test show strong correlation coefficients and, thus, all have the possibility to be used in the prediction of flexural strength. The report suggests a new process for acceptance testing based on using a combination of compressive strength and seismic modulus. The selection of compression testing is based on the perceived know-how of the personnel of NCDOT throughout the State.

US Transportation Collection