Minimum length of passengercaronlyacceleration single lane of highway(PDF)
长安大学学报（自然科学版）[ISSN:1006-6977/CN:61-1281/TN]
- Issue:
- 2021年5期
- Page:
- 107-117
- Research Field:
- 交通工程
- Publishing date:
Info
- Title:
- Minimum length of passengercaronlyacceleration single lane of highway
- Author(s):
- PAN Binghong; LI Xiang
- (School of Highway, Changan University, Xian 710064, Shaanxi, China)
- Keywords:
- traffic engineering; minimum length of acceleration lane; calculation model of length; POASL; SPCT; ramp
- PACS:
- -
- DOI:
- -
- Abstract:
- In order to fill the gap in the design of the separation of passenger cars and trucks (SPCT) interchange, and to provide the theoretical support for the relevant design, the minimum length of passengercaronlyacceleration single lane (POASL) on freeway was studied based on the driving characteristics of passenger cars. First of all, by analyzing effect of the design speed of main lane and ramp, acceleration performance of passenger cars on the acceleration zone, and the effect of the characteristics of time headway of inflow traffic flow, design traffic capacity of main line and minimum headway on the waiting zone, the length calculation model of acceleration zone, waiting zone and triangle gradient section were established. Secondly, by selecting the reasonable speed and acceleration characteristic parameters of the passenger cars in the domestic and foreign codes, the key indexes in the calculation model were determined, and the recommended minimum length of the POASL was put forward through calculation. Finally, the influence of different longitudinal slopes on the confluence of passenger cars was analyzed, and the longitudinal slope correction coefficient of the acceleration zone was proposed. The results show that the minimum length of the acceleration lane specified in Chinese code merely meets the requirements of the design speed of the ramp is greater than or equal to 50 km/h. If the design speed of ramp is less than 50 km/h, the standard value is too short to meet the requirements of safe confluence. Therefore, it is appropriate to increase the minimum length of acceleration specified in code appropriately. When an acceleration lane is located uphill, only the minimum length of the acceleration zone needs to be corrected, rather than the entire length of acceleration lane. The parallel acceleration lane is shorter than the directlylinked type acceleration lane, and the difference between them increases with the enlargement of design speed. Considering occupation, the parallel acceleration lane is more economical for POASL. 9 tabs, 8 figs, 28 refs.
Last Update: 2021-09-30