Measurement of Stress Based Load Transfer Efficiency Using Single Gage Under Moving Multi-axle Carriages at the National Airport Pavement Test Facility

Abstract

It is currently believed that mechanistic evaluation of rigid pavements using full scale test data is the most appropriate way to study pavement behavior. Current methods outline a single and dual gage approach for evaluating stress-based load transfer efficiency (LTE (S)) at the transverse joints. The single gage method can be very useful for joints where only a single gage is located or where dual gages are located, but only one of the gages is producing accurate responses. Additionally, the installation and monitoring of gages is expensive; therefore, the ability to accurately calculate the stress-based load transfer efficiency based on a single gage will provide an impetus to several resource starved agencies to monitor the performance of the joint without the need to install two gages. Both methods have produced similar estimations of LTE (S) for single axle carriages; however, it is unknown if this approach yields similar results for multi axle carriages. The dual gage approach for measuring LTE(S) has been implemented successfully in prior studies at Rowan University for tandem axle configurations for testing conducted on Construction Cycle 2 (CC2) at the Federal Aviation Administration (FAA) National Airport Pavement Test Facility (NAPTF). In this study LTE(S) was determined based on a single gage for multi-axle carriages. The analysis was conducted on CC2 and CC6 test items. The LTE(S) calculated based on a single gage was then compared with those calculated with the dual gage. This analysis has shown mixed results and limitations regarding the accuracy of the stress-based LTE using a single gage.