|Table of Contents|

Gentle slope design indexes of long downhill in mountainous expressway(PDF)

长安大学学报（自然科学版）[ISSN:1006-6977/CN:61-1281/TN]

Issue:
2024年1期
Page:
1-12
Research Field:
道路工程
Publishing date:

Info

Title:
Gentle slope design indexes of long downhill in mountainous expressway
Author(s):
ZHANG Chi1;  WANG Han1;  FU Zhi-peng2;  HOU Yu-di3;  BAI Hao-chen2
(1. School of Highway, Chang'an University, Xi'an 710064, Shaanxi, China; 2. CCCC First Highway Consultants Co. Ltd., Xi'an 710075, Shaanxi, China; 3. Guangzhou Municipal Engineering Design and Research Institute Co. Ltd., Guangzhou 510095, Guangdong, China)
Keywords:
road engineering;  design of transition slope;  experimental research;  downhill characteristics of truck;  continuous long downhill slope;  brake hub temperature
PACS:
U412.33
DOI:
10.19721/j.cnki.1671-8879.2024.01.001
Abstract:
In order to clarify the design criteria for extended downhill grades on mountainous highways in China, with a primary focus on articulated six-axle trucks, an analysis was conducted based on the principles of vehicle dynamics. The acceleration characteristics of trucks descending long slopes was examined, using engine-assisted braking and the heat dissipation characteristics of brake hubs. Initially, mechanical equilibrium equations were formulated, and a gear-speed-critical gradient model was developed to determine the critical gradient for gentle slopes under various speed and gear conditions. Subsequently, considering the design constraints of highways in China and the operational characteristics of trucks, the critical gradients corresponding to the 12th and 11th gears were adopted as the control indicators for highway gentle slope design. The design criteria and methods for continuous downhill and gentle slope sections were proposed. Finally, utilizing an entry speed of 70 km/h as an example, a comparison was made between the gentle slope length criteria obtained based on speed reduction and temperature reduction characteristics. Additionally, an analysis was performed, combining the results with an optimized design of a highway in the Southwestern Mountainous Region. The results show that introducing gentle slope sections between continuous long downhill segments contributes to brake hub temperature reduction and restoration of truck braking performance. Based on speed characteristics, different gentle slope lengths are determined for speed reductions of 10 and 20 km/h under varying gentle slope gradients. The gentle slope length based on temperature characteristics is calculated under the least favorable condition of brake hub failure temperature at 260 ℃, considering different operating speeds and temperature reduction values. The gentle slope length obtained based on speed reduction characteristics provides valuable guidance for longitudinal slope design, while the length obtained based on temperature reduction characteristics, although relatively large, is not suitable for design but can be used for evaluation. The continuous downhill and gentle slope design-evaluation process is summarized. Using a highway in the Southwestern Mountainous Region as an example, the analysis reveal that reasonable values for the gradient and length of gentle longitudinal slopes effectively improve brake hub temperatures and enhance the safety of vehicles traveling on continuous long downhill segments.6 tabs, 7 figs, 34 refs.

References:

[1] 国家统计局.中国统计年鉴[M].北京:中国统计出版社,2017.
National Bureau of Statistics.China statistical yearbook[M].Beijing:China Statistics Press,2017.
[2]JTG B01—2014,公路工程技术标准[S].
JTG B01—2014,Technical standard of highway engineering[S].
[3]JTG D20—2017,公路路线设计规范[S].
JTG D20—2017,Design specification for highway alignment[S].
[4]BOWMAN B L.Grade severity rating system[J].ITE Jounal,1990,60(7):19-24.
[5]COLEMAN M.Use of auxiliary brakes in heavy vehicles[R].Sydney:Austroads,2014.
[6]廖军洪,邵春福,邬洪波,等.连续长大下坡心率与线形指标关系模型[J].交通运输系统工程与信息,2012,12(4):184-189.
LIAO Jun-hong,SHAO Chun-fu,WU Hong-bo,et al.Modeling drivers' heart rate and highway alignment relationship on long steep downgrades[J].Journal of Transportation Systems Engineering and Information Technology,2012,12(4):184-189.
[7]阎 莹,刘浩学.山区公路纵坡路段线形指标对驾驶员心理生理影响研究[J].武汉理工大学学报(交通科学与工程版),2008,32(6):1013-1016.
YAN Ying,LIU Hao-xue.Study on effect of alignment index of longitudinal slope sections of mountain roads on drivers' psychology and physiology[J].Journal of Wuhan University of Technology(Transportation Science & Engineering),2008,32(6):1013-1016.
[8]张 娟.基于驾驶员因素的公路连续长坡路段线形研究[D].西安:长安大学,2012.
ZHANG Juan.Study on alignment of continuous long slope sections of highway based on driver factors[D].Xi'an:Chang'an University,2012.
[9]周荣贵,江立生,孙家风.公路纵坡坡度和坡长限制指标的确定[J].公路交通科技,2004,21(7):1-4.
ZHOU Rong-gui,JIANG Li-sheng,SUN Jia-feng.The study of highway gradient and grade length limit[J].Journal of Highway and Transportation Research and Development,2004,21(7):1-4.
[10]周 磊.连续下坡路段汽车行驶特性与制动器制动性能研究[D].西安:长安大学,2007.
ZHOU Lei.Study on vehicle driving characteristics and braking performance of brakes on continuousdownhill sections[D].Xi'an:Chang'an University,2007.
[11]付焱鑫.新疆乌尉高速长大纵坡事故易发位置辨识及交通安全保障措施研究[D].武汉:武汉工程大学,2017.
FU Yan-xin.Study on accident-prone location identification and traffic safety guarantee measures of Wuwei Expressway in Xinjiang[D].Wuhan:Wuhan Institute of Technology,2017.
[12]丁志勇,周子楚,郭忠印.运行速度预测模型在公路长大纵坡路段设计中的适用性分析及修正[J].公路工程,2016,41(5):118-122,138.
DING Zhi-yong,ZHOU Zi-chu,GUO Zhong-yin.Modification of the operating speed prediction model in the long and steep downgrade[J].Highway Engineering,2016,41(5):118-122,138.
[13]林 声,郭忠印,周小焕,等.公路线形空间几何特性模型及其应用[J].中国公路学报,2010,23(增2):47-52.
LIN Sheng,GUO Zhong-yin,ZHOU Xiao-huan,et al.Models of highway alignment spatial geometric properties and their applications[J].China Journal of Highway and Transport,2010,23(S2):47-52.
[14]JTG B05—2015,公路项目安全性评价规范[S].
JTG B05—2015,Specifications for highway safety audit[S].
[15]潘兵宏,牛 肖,白浩晨,等.高速公路连续下坡路段货车制动毂温升模型修正研究[J].公路交通科技,2021,38(9):85-91.
PAN Bing-hong,NIU Xiao,BAI Hao-chen,et al.Study on temperature rise model of truck brake hubs on continuous downhill section of expressway[J].Journal of Highway and Transportation Research and Development,2021,38(9):85-91.
[16]李清波,谢 珍.公路纵坡设计的理论分析[J].长沙交通学院学报,1998(3):40-46.
LI Qing-bo,XIE Zhen.The theoretical analysise of highway longitudinal grade design[J].Journal of Changsha Communications University,1998(3):40-46.
[17]张 驰,侯宇迪,杨 坤,等.公路长大下坡路段货车制动毂温升模型研究综述[J].长安大学学报(自然科学版),2019,39(3):96-107.
ZHANG Chi,HOU Yu-di,YANG Kun,et al.Review of brake drum temperature rise model for vehicle on long and steep downgrades of highway[J].Journal of Chang'an University(Natural Science Edition),2019,39(3):96-107.
[18]王宏权.粤东山区复杂地质条件下特长公路隧道路段线路方案研究[J].中外公路,2021,41(2):256-260.
WANG Hong-quan.Research on line schemes of extra-long highway tunnel with in complicated geological condition in mountains of East Guangdong Province[J].Journal of China & Foreign Highway,2021,41(2):256-260.
[19]陈 斌,袁 伟,付 锐,等.连续长大下坡路段交通事故特征分析[J].交通运输工程学报,2009,9(4):75-78,84.
CHEN Bin,YUAN Wei,FU Rui,et al.Analysis on the characteristics of traffic accidents in continuous long and steep downhill sections[J].Journal of Traffic and Transportation Engineering,2009,9(4):75-78,84.
[20]郭腾峰.长大纵坡安全与车路协同矛盾探究[J].中国公路,2018(2):62-65.
GUO Teng-feng.Study on the contradiction between safety of long longitudinal slope and coordination between vehicle and road[J].China Highway,2018(2):62-65.
[21]赵含雪.基于发动机制动和排气制动的重型商用汽车长大下坡安全性研究[D].西安:长安大学,2014.
ZHAO Han-xue.Study on safety of heavy commercial vehicles on long downhill based on engine braking and exhaust braking[D].Xi'an:Chang'an University,2014.
[22]赵含雪,王金洋.重型商用汽车排气制动下坡能力研究[J].甘肃科技,2014,30(9):38-40,128.
ZHAO Han-xue,WANG Jin-yang.Study on downhill braking ability of heavy commercial vehicles by exhaust[J].Gansu Science and Technology,2014,30(9):38-40,128.
[23]肖润谋,叶燕仙,周晓悦,等.发动机制动失效的坡长临界值计算[J].交通运输工程学报,2006,6(4):122-126.
XIAO Run-mou,YE Yan-xian,ZHOU Xiao-yue,et al.Critical slope length computation of engine brakeinefficacy[J].Journal of Traffic and Transportation Engineering,2006,6(4):122-126.
[24]吴明先,杨军超,林宣财,等.高速公路下坡路段缓坡安全性设计研究[J].公路交通科技,2021,38(9):92-97,104.
WU Ming-xian,YANG Jun-chao,LIN Xuan-cai,et al.Study on design of gentle slope in continuous downhill section of expressway[J].Journal of Highway and Transportation Research and Development,2021,38(9):92-97,104.
[25]侯宇迪.基于制动毂温升的高速公路连续下坡设计优化方法研究[D].西安:长安大学,2020.
HOU Yu-di.Research on optimization method of continuous downhill design of expressway based on temperature rise of brake hub[D].Xi'an:Chang'an University,2020.
[26]汪双杰,周荣贵,孙小端.公路运行速度设计理论与方法[M].北京:人民交通出版社,2010.
WANG Shuang-jie,ZHOU Rong-gui,SUN Xiao-duan.Highway design theory and method based on operating speed[M].Beijing:China Communications Press,2010.
[27]WEBB C R.The effect of gradient on fuel consumption and speed of a road vehicle[J].Proceedings of the Institution of Mechanical Engineers:Automobile Division,1952,6(1):104-117.
[28]苏 波.大货车持续制动性能与山区高速公路纵坡优化设计研究[D].上海:同济大学,2009.
SU Bo.Study on continuous braking performance of large trucks and optimal design of longitudinal slope of mountainous expressway[D].Shanghai:Tongji University,2009.
[29]周荣贵,徐建伟,吴万阳.公路连续下坡路段的纵断面控制指标研究[J].公路,2004,49(6):46-51.
ZHOU Rong-gui,XU Jian-wei,WU Wan-yang.Study on longitudinal control index of continuous downhill section of highway[J].Highway,2004,49(6):46-51.
[30]郭腾峰,张志伟,刘 冰,等.适应6轴铰接列车动力性的高速公路最大纵坡坡度和坡长[J].交通运输工程学报,2018,18(3):34-43.
GUO Teng-feng,ZHANG Zhi-wei,LIU Bing,et al.Maximum grade and length of longitudinal slope adapted to dynamic performance of six-axis articulated vehicle[J].Journal of Traffic and Transportation Engineering,2018,18(3):34-43.
[31]胡昌斌,沈金荣,陈友杰.长下坡路段货车毂式制动器摩擦衬片温升规律[J].交通运输工程学报,2009,9(4):49-55.
HU Chang-bin,SHEN Jin-rong,CHEN You-jie.Temperature rise law of friction lining of freight car hub brake on long downhill section[J].Journal of Traffic and Transportation Engineering,2009,9(4):49-55.
[32]张 驰,胡 涛,侯宇迪,等.基于制动毂温升的连续下坡货车事故风险评价模型[J].华南理工大学学报(自然科学版),2020,48(11):19-29.
ZHANG Chi,HU Tao,HOU Yu-di,et al.Crash risk evaluation model based on brake heating for trucks under continuous downhill road conditions[J].Journal of South China University of Technology(Natural Science Edition),2020,48(11):19-29.
[33]杨宏志,胡庆谊,许金良.高速公路长大下坡路段安全设计与评价方法[J].交通运输工程学报,2010,10(3):10-16,40.
YANG Hong-zhi,HU Qing-yi,XU Jin-liang.Safety design and evaluation method of long and steep downhill section of expressway[J].Journal of Traffic and Transportation Engineering,2010,10(3):10-16,40.
[34]张 驰,侯宇迪,秦际涵,等.基于制动毂温升的连续下坡安全设计方法[J].华南理工大学学报(自然科学版),2019,47(10):139-150.
ZHANG Chi,HOU Yu-di,QIN Ji-han,et al.Safety design method of long slope downhill slope based on temperature increase of brake drum[J].Journal of South China University of Technology(NaturalScience Edition),2019,47(10):139-150.

Memo

Memo:
-
Last Update: 2024-01-10