Studies On The Setting Of Safety Facilities At Interchanges During Highway Reconstruction

During freeway expansion, due to the expansion interchanges is an "every one of building an interchange" pattern, interchanges' traffic relatively increased, construction personnel, construction machinery, guardrail in roadside and the vehicles constituted a dangerous and complex traffic environment, forcing the service level of the interchanges decline, road safety coefficient reduced. This paper takes a study of interchanges safety problems of freeway expansion, and then put forward a series of effective safety facilities set scheme, ensure safety and unblocked in the interchanges. It's a further perfection from "face" to "dot" following the unblocked technology research of freeway expansion project.This article introduced the definition and pattern of interchanges expansion project flowing the definition and types of interchanges, and combined the transportation characteristics of interchanges during expansion, at last, analyzed drivers, vehicles and road characteristics of interchange expansion area.According to the relevant data which collected during the freeway expansion, analyzed detailly the safety at the interchange entrance from traffic volume, vehicle types proportion and driving velocity, got a relationship between traffic conflict and three influence factors which mentioned above. Then studied safety facilities at the interchanges during freeway expansion, especially temporary security facilities, analyzed the basic requirement of setting safety facilities, put forward schemes of traffic signs, traffic reticule, makeshift isolation facilities and so on; Discussed the problem, where and how to set the speed limit sign, marked line and temporary traffic safety facilities at the entrance of interchanges in detail.Finally, combined with the specific conditions of the typical interchanges expansion project from Xi'an to Baoji section of freeway (G30), discussed safety facilities set of different expansion model at the entrance of interchanges, ensure the traffic are unobstructed and safety during freeway expansion.