Assessment of AASHTO Provisional Standards for Profile Data Collection and Interpretation

Abstract

The Kansas Department of Transportation (KDOT) currently uses a comprehensive, network-level pavement management system (PMS) known as the network optimization system (NOS). Annual condition surveys for roughness, rutting, and faulting generate important inputs for NOS. Recently, AASHTO published provisional standards for condition surveys to harmonize data collection efforts among the states. To study the effects of these provisional standards on KDOT NOS, profile data were collected on about 320 km (201 mi) of Kansas highways according to these standards. The comparison data came from KDOT's annual condition survey with KDOT standards. The roughness values, in terms of international roughness index, were computed and aggregated for 20 test sections; rut depths were computed and compared for 16 test sections; and the fault values were computed and compared for 4 test sections. Various statistical analyses compared the results from the algorithms, according to KDOT NOS and AASHTO provisional standards. The roughness measurements and subsequent analysis using AASHTO provisional standard PP 37-00 and current KDOT methodology tend to produce statistically similar results. This may indicate that the PP 37-00 standard can be adopted for NOS without any major changes in current practice. The four-level stratification for rut-depth severity suggested by AASHTO PP 38-00 compares reasonably well with the current NOS practice. Both algorithms compared well for 3 composite pavement test sections and on 7 of 13 bituminous sections. On these sections, the effects of 0.16-km (0.1-mi) and 0.1-km (0.0625-mi) aggregation are insignificant. The dissimilarities on other sections may result from the outer sensors in the five-sensor configuration required by AASHTO PP 38-00. However, significant differences were found in calculated fault values from the two methods, even after some modification to PP 39-00.