CORRELATION OF LABORATORY TESTS TO FIELD PERFORMANCE FOR CHIP SEALS

The Nevada Department of Transportation constructed 44 chip-seal test sections between Yerington and Wabuska, Nevada. One of the purposes of these test sections was to correlate laboratory and field testing with pavement performance. The laboratory testing consisted of the Vialit-time series and the Vialit-temperature series. Field testing included only the Vialit-time series. Pavement performance was based on pavement evaluations and percent reflective cracking. The pavement evaluations recorded overall condition, aggregate retention, aggregate embedment, and bleeding. After a comparison of the field and laboratory testing with pavement performance three conclusions were drawn: (a) the field Vialit-time series testing did not correspond to laboratory Vialit-time series testing because of the variation in curing temperature of the field samples; (b) the laboratory Vialit-temperature series can detect the effects of aggregate gradation on different binders; and (c) aggregate retention of the sample cured at 0 deg F is a good indicator of overall chip-seal performance. Ratings of 8.0 or greater are likely for overall condition and aggregate retention if the percent aggregate retention for the laboratory sample cured at 0 deg F is greater than 60%.