Evaluation of a Line Laser Scanner to Improve the Measurement of Average Least Dimension in Chip Seal Design Methods

Chip seal, as the most widespread pavement preventive treatment, is regularly applied on existing pavements that are still in good structural condition to increase the pavement serviceability. The most effective key parameter on chip seal performance is binder application rate, which directly governs chip seal distresses such as bleeding and raveling. How this rate is calculated mainly depends on the value of least dimension (LD) of aggregate particles. However, the available measuring methods of LD value are slow, laborious, and subjective. This study presents the development of a new high-speed line laser scanner (LLS) prototype to measure the LD value of particles more quickly and accurately. The LD values of aggregate particles were also measured using a digital caliper and considered as control data. The repeatability and reliability of the developed LLS prototype were evaluated, as well as the speed of the prototype in calculating the LD values of 100 aggregate particles. The findings indicate that the measurements of the developed prototype are highly correlated with those of the caliper. In addition, it was found that the developed prototype is efficient and capable of calculating the LD values of several particles simultaneously.