Long-term Cost-effectiveness of Asphalt Pavement Pothole Patching Methods

摘要

Throw-and-roll and semi-permanent are frequently used pothole patching techniques for asphalt pavement. To evaluate the cost-effectiveness of the two patching techniques with different combinations of materials and procedures, a 14 months survey was conducted to investigate field performance of patches installed on road sections with varying weather and traffic conditions. The performance of a patch was rated according to its overall distress conditions. By rating failed patches as 0, the service time was considered in the performance index. Multiple linear regression method was utilized to analyze the influence of patching methods, materials, geometric features, climatic condition and traffic factors on the performance of patches. Field survey found that the throw-and-roll patches installed in winter deteriorated very fast, mainly due to severe freezing environment and insufficient compaction and curing. 70% throw-and-roll patches lasted less than 14 months. The patches that survived through the first winter, were typically well compacted, fully cured, and tended to last much longer. Labor cost accounts for 50 to 60% of the total cost, whereas material cost only accounts for 20% for cold mixes and 2~5% for semi-permanent patches. Due to the reduced equipment and labor costs, the throw-and-roll patches had higher cost19effectiveness in short term. However, the effectiveness of throw-and-roll patches decreased rapidly and semi-permanent patches exhibited higher cost-effectiveness in long term. To improve the stability of patches, it is of great importance to apply sufficient compaction during installation.