Optimizing lighting conditions for nighttime highway construction operations.

摘要

The application of nighttime construction in highway maintenance and rehabilitation projects has been increasing in recent years in order to reduce construction-associated traffic disruptions. Proper and adequate lighting arrangements need to be provided on nighttime construction sites to enable construction activities to be performed safely and with satisfactory quality. The major objectives of this research are to: (1) develop a practical framework for establishing practical lighting design criteria that can be incorporated in state departments of transportation (DOTs) standards to ensure proper and adequate lighting conditions in nighttime work zones; (2) develop a lighting design model for nighttime construction operations that can be utilized by both contractors and resident engineers in the development, implementation, and inspection of practical lighting designs that satisfies all state DOTs requirements; and (3) develop a decision support system for lighting nighttime work that can be utilized to search for and identify near optimal design solutions.; First, a practical framework named Construction Visual Requirements Framework " CONVISUAL" is developed to establish objective lighting design criteria for nighttime highway construction in order to minimize the subjectivity and discrepancy in available lighting standards adopted by different DOTs. The framework can be utilized by state DOTs as performance-based criteria that quantifies and assigns the required lighting levels for various construction tasks. Second, a lighting design model, "CONLIGHT", is developed for nighttime highway construction. The model performs lighting calculations that evaluate the impact of all lighting design parameters on the lighting design criteria. Four computational modules are included in the CONLIGHT model to calculate average illuminance, lighting uniformity, glare, and cost. The model can be utilized to verify that the selected lighting arrangement complies with all lighting design requirements. Third, a decision support system is developed utilizing the CONLIGHT model and a multi-objective genetic algorithm. The developed system is capable of: (1) maximizing average illuminance on construction sites; (2) maximizing lighting uniformity in the work zone; (3) minimizing glare to workers and road users; and (4) minimizing lighting costs, simultaneously. The system provides near optimal trade-offs among the aforementioned conflicting design objectives.