Laboratory Test Methods and Field Correlations for Predicting the Performance of Chip Seals

Eighteen chip seal test sections were place in two states (Washington, Nevada). Four emulsions were used in the construction of these sections: cationic rapid set (CRS-2), cationic medium set (CMS-2), latex modified cationic rapid set (LMCRS-2), and a high float (HFE 100S). Variations in aggregates included: aggregate source, aggregate gradation, and precoating of aggregates.

Laboratory testing with the Vialet test was performed using construction materials and quantities. Laboratory test results were evaluated for the presence of excess aggregates and the set rate of the emulsions. Laboratory results were then compared to field comments.

Guidelines to avoid construction problems were outlined. In general, Vialet test results of less than 30% material retained indicate that problems with aggregate pickup on rollers could be expected. Results of less than 65% indicate potential damage by early brooming of new chip seals. Results greater than 80% provided satisfactory field performance after one month of low-volume traffic.