Resumen
The effect of operation safety of expressway tunnels on operation efficiency of the expressway network is significant because tunnels are key sections in the network. In case of emergency, e.g. traffic accidents, it brings much difficulty to rescue work and may paralyze traffic in the tunnel and even that of the entire expressway. In order to guarantee the tunnel operation safety, it is necessary to monitor the operation of tunnels and take effective measures to keep safety under control. This paper focuses on operation risk modeling of expressway tunnels and development of a monitoring-warning system for real time expressway tunnel operation control. The research includes an investigation of expressway tunnel operation, risk analysis, development of risk modeling and intelligent monitoring-warning system and a pilot project. Over thirty cases of expressway tunnel operation were investigated and filed data of the operation situations including traffic accidents, running speed, acceleration and deceleration of vehicles were collected. Then, the operation conditions and risks were analyzed and the operation risk model was then developed to solve the problem. Based on the investigation data of the tunnel operation, five types of emergency incidents were identified and classified with regard to the effect of incidents on the tunnel operation risks and efficiency. The emergency incidents were defined respectively as traffic incidents, severe weather, overspeeding, dangerous goods transportation and scheduled event. These incidents were graded in relation to the levels of effect on tunnel operation safety. Comprehensive traffic control measures for each incident were put forward respectively in order to achieve effective tunnel traffic management, which included speed limit, safe driving distance, closed lanes and traffic guides. To implement real time control and effective tunnel operation management, an intelligent tunnel monitoring-warning system including the system software and relative equipment were developed with functions of information collection, information processing and transmission and information release. A pilot project has been implemented at Huotanwan tunnel (left line) on the Baomao expressway (G65) in Hunan province, China.