Assume a collision occurs at 10:30 PM on the westbound of a 4-lane bridge (2-lane in each direction) blocking the entire roadway. When the accident happens, the traffic volume is around 1200 veh/hr. Emergency crew responded quickly to open 1 lane within 30 minutes, and then fully reopen the roadway 25 minutes after that. The westbound roadway capacity and one lane capacity are 3690 and 1845 veh/hr, respectively. The problem specifications are given below: Table 1: Problem inputs Roadway capacity 3690 veh/hr One lane capacity 1845 veh/lane/hr Both lane closure time 30 minutes One lane closure time 25 minutes Total incident time 55 minutes Flow rate 1200 veh/hr