Investigation of winter tenting of transverse cracks in asphalt pavement

Abstract

In winter, asphalt pavement in the colder regions exhibits a localized secondary distress called pavement tenting. It occurs when the ice accumulates underneath the transverse crack, pushing either side of the crack upward. The conventional theory behind its formation is the frost heave of the base materials. The presence of moisture underneath the transverse crack plays the most significant role in its development. The infiltration of deicing salt into the crack, resulting in the osmosis phenomenon, often catalyzes the tenting’s development. Tenting increases the pavement roughness and transverse crack deterioration rate. The main objective of this study is to determine the potential mitigation strategies for the tenting problem and establish aggregate base gradation control parameters that can reduce the tenting occurrence.This study analyzed pavement roughness data of different asphalt road sections of Minnesota where the critical distress of the sections was transverse crack. Data was collected from the Minnesota Department of Transportation (MnDOT) road performance database with a computer application named Highway Pavement Management Application (HPMA). The effectiveness of different maintenance measures was computed based on their percentage change in the international roughness index (IRI) before and after the application of any treatment. The maintenance methods/ treatments were based on the composite score, which represents the relative mean effectiveness of different treatments. Different laboratory tests were performed to determine the relationship between the base materials properties corresponds to the tenting susceptibility. One-dimensional frost heave tests were conducted on four different aggregate base materials having different gradation, fine, and salt content. A Hydraulic conductivity test was also conducted to determine the ability of the base to drain the water. Distress data analysis showed that micro-surfacing has a good potential to keep the road roughness low for the pavements. In terms of localized crack maintenance methods, crack repair showed the highest composite score in all types of pavements compared to others. The laboratory test results showed that the particle size distribution, particularly coarse void to fine void ratio (CV/FV index), significantly correlates with the base materials performance in relation to tenting sensitivity. The aggregate base layer with a higher CV/FV index will exhibit better resistance to differential frost heaving or tenting.