Toward a framework for management of hot-mix asphalt (HMA) construction operation.
详细信息
文摘
Highway construction is known to be the most conservative segment of the construction industry and the current practices of Hot-Mix Asphalt HMA) construction are based upon experience. HMA construction needs better process control,monitoring,and feedback documentation to meet the new requirements set by the SuperpaveTM and Quality Control/Quality Assurance QC/QA) programs. The quality of finished HMA pavement has significant financial implications to HMA contractors and is important to owners and users because it is related to savings,riding comfort,and safety. Factors affecting quality of HMA pavement are material properties,mix properties,mix design,compactive effort,temperature,thickness of mat,and subgrade support. Most of these factors can be monitored in real-time using state-of-art technologies that are investigated in this research. Multiple linear regression analysis of 1997 Arizona Department of Transportation data shows that the aggregate gradation and asphalt cement contents have significant effect on the densification of HMA. During this analysis,it was learned that the correlation occurs between independent variables because of the inherent nature of testing procedures. Principal Component Analysis PCA) solves this multicollinearity problem. The PCA on the Arizona data shows that the quadratic and cubic patterns are highly significant in explaining air voids. This presents the fact that PCA is the methodology to logically explain the effect of variation in aggregate gradation on the densification of HMA. The framework for the field management of the HMA operations is developed and proposed using a systems approach,with the emphasis on the quality aspects of HMA pavement. The target of the framework is to balance productivity and quality to maximize the profit to the contractor. The dynamic nature of the HMA operations and their susceptibility to unpredictable variables make this balancing act difficult. However,careful analysis on this balancing act is desirable for successful project completion. The framework is supported by currently available state-of-art technologies. These technologies are comprehensively reviewed,and selected technologies are recommended for the future development of the field management system. The deficiencies of the current technologies are investigated and the demanding characteristics of technologies are discussed.