Vehicle load effect of expressway bridge in the state of lanes merging(PDF)
长安大学学报（自然科学版）[ISSN:1006-6977/CN:61-1281/TN]
- Issue:
- 2017年01期
- Page:
- 76-84
- Research Field:
- 桥梁与隧道工程
- Publishing date:
Info
- Title:
- Vehicle load effect of expressway bridge in the state of lanes merging
- Author(s):
- XIA Zhang-hua; CHEN Jun-min; ZONG Zhou-hong; LIN You-qin
- 1. College of Civil Engineering, Fuzhou University, Fuzhou 350108, Fujian, China; 2. Fujian Academy of Building Research, Fuzhou 350002, Fujian, China; 3. School of Civil Engineering, Southeast University, Nanjing 210096, Jiangsu, China
- Keywords:
- bridge engineering; vehicle load effect; random load flow; lanes merging state; extreme value distribution
- PACS:
- U441.3
- DOI:
- -
- Abstract:
- In order to obtain the effect of vehicle load on bridge structure in the state of lanes merging, vehicle load effect analysis method for expressway bridge was studied based on vehicle load data collected by WIM system on a continuous girder bridge. Firstly, according to the feature of lanes merging of vehicles, basic distribution characteristics of vehicle load including vehicle weight, axle load, axle spacing and vehicle spacing were obtained by using EM calculation method. Secondly, to solve two cases in the state of lanes merging, including decrease of vehicle spacing and vehicle jam the corresponding random vehicle load flow simulation method was presented. Finally, bridge load effect evaluation value in the state of lanes merging was obtained by combining stochastic vehicle influence line and extreme value distribution theory, and the influence of vehicle spacing on load effect was studied. The results show that the total vehicle weight, axle weight and axle spacing obey the mixed Gauss distribution, and the vehicle spacing obeys the logarithmic normal distribution. The present method can be well applied to analysis of the vehicle load effect in the state of lanes merging, and the load effect are about 1.13 and 1.03 times of the exceeded truck-20 and the highway grade Ⅰ respectively. When is the lanes merging and vehicle jam happening in meantime, the corresponding vehicle load effect are 1.29 and 1.17 times of the exceeded truck-20 load effect and the highway grade Ⅰ respectively. It is also found that effect of vehicle spacing linearly relates to the distance between two vehicles when vehicle spacing is between 2~5 m, and the actual vehicle load effect is definitely less than the design vehicle load effect when vehicle spacing is controlled at more than 10 m. The research results can provide references for the evaluation of bridge carrying capacity and the traffic control in the state of lanes merging.
Last Update: 2017-01-22