Study On Optimization Of The Traffic Organization For Off-road Public Parking Lot

With the rapid growth of the car ownership per capita, the car parking demand in the city increasing in a high speed and contradiction between parking supply and demand also becoming saliently day by day, One of the reasons that cause this problem is that the function of the parking facilities has not been fully used under the existing supply condition of the traffic facilities. Therefore, the paper started from the problem of the ―supply‖ in the parking facilities. Then the traffic organization optimized method of the off-road public parking lot and its simulation evaluation were given out. Hoping to make full use of the existing facilities and reduce the interference to the nearby traffic. The main works of the paper are listed as below:Firstly, according to the study of off-road public parking lot at home and abroad, the parking characteristics and the traffic properties of vehicle access has been analyzed in detail, and the basic rules between parking lot traffic and urban traffic have been received.Secondly, by analyzing the influence factors of traffic organization range, the scope of off-road public parking traffic organization has been determined. The off-road public parking lot traffic organization optimization has been researched from the following aspects. ① For the three basic form of vehicle access, the length of vehicle access was optimized by using the queuing theory and sight distance triangle; ② For large parking lot vehicle access spacing model were discussed in two different conditions. One is from single spacing between exits, the other is spacing between vehicle access; ③ The different aspects of the optimization for Internal optimizing traffic organization,outside traffic organization,traffic guidance facility layout etc.Then, on the basis of considering many factors of the parking lot traffic system and combing with the VISSIM simulation software evaluation indexes, the measurement indexes of access traffic organization optimization system were set up. By taking with the information entropy, membership function etc. the traffic origination evaluation model was built.Finally, taking the ANNING district of Lanzhou city off-road public parking as an example, through questionnaire methods and field observation records, its parking lots were investigated and analyzed. The length and the spacing between the vehicle accesses of typical off-road public parking lots were calculated. Combining with traffic simulation software of VISSIM, the model was verified. The traffic organization optimization scheme of the parking lot was built in different grade roads by using the matter-element evaluation model. And its evaluation results were expressed through quantitative data.The results shows that all parking delays have significantly lower, the calculation model is feasible and the optimization method is the most obvious effect on trunk road. This indicates that improving parking lot access length and the spacing between the accesses have great effect on improving the utilization rate of the parking lot and reducing the disturbance to the surrounding traffic.