Research On The Key Design Technology Index Of Left-in Interchange Ramp

Restricted by many factors,Urban planning and construction of mountain interchange is different from plain city,.Especially for such a large mountain city of Chongqing.Because of the high intensity of land development,urban traffic land road construction is severely restricted.As of year 2014,the main city of Chongqing's vehicle ownership was 1.151 million,went into a phase of rapid growth since 2007,the annual average growth rate is more than 15%.In urban road development,by the end of year 2014,the main city district of Chongqing,the total road length is 3730 km,there was a a substantial increase compared to year 2007's 2119.2km.Road length in the main city experienced rapid growth in 2007-2010 after since 2010 in the overall slow growth,the average annual growth rate of less than 4%.Thus due to the mountainous urban land constraints,the development of urban mountain roads subject to strict controls on the amount,construction by its mountainous topography and urban development constraints.Urban Road original intersection's reconstruction to interchange is already built on the quality of the road itself will be improved.However,due to mountainous intersection in city surrounding land has been developed,the high cost of demolition,and very uneconomical.Interchange wiring is restricted,it is difficult for detour wiring,constrained by the Turn left traffic demand and the intersection of the road grade,etc.The rebuilt interchange of The Chongqing GuMufeng Intersection taken "out of left into left" orientation ramp for turning left.Because our vehicles drive on the right,the vehicle cab of the vehicle was settled in the left front of vehicle.So that the driver have different fields of view,and therefore there is a certain safety hazard on left-in ramp.Based on the Urban Interchange construction land constraints,the level of the road intersection,turn left traffic demand and the character of Left-in ramp.investigate its applicability in urban planning and construction of the Interchange.If it itself does not have any suitable value,then explore its security is meaningless.In determining which has a special meaning in the mountain city Interchange Construction premise.First studied for the vehicle's blind spot.Discussion blind spot due to the physical nature of the vehicle itself obscured dead zone caused by theposition of the cab,blind spot mirrors differences in left and right sides of the vehicle.Such differences lead to security risks.On the basis of the security risks of sit-in Interchange discuss safety design.After about vehicle blind study found that differences do exist.However,China's specification does not reflect this difference.Ramp traffic flow inlet connection does exist centralized conflict.On this basis,for the basic segment linear ramp design speed,each index inlet connector design safety recommendations.Recommendations for safe design,three different forms of the entrance ramp connecting portion designed to,Chongqing GuMufeng interchange as an example,under the same conditions of mainline traffic,converting traffic ramp(9 different sets of assumptions and a ramp traffic set of actual flow),three ramp connecting the inlet portion forms respectively,for which the traffic flow,make reference for the design suggestions.