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Study on the Applicability and Modification of the Design Hourly Volume on Rural Expressways Considering Holiday
Fangchen Ma1, Jinliang Xu1, Chao Gao1
1College of Highway, Chang'an University, Xi'an 710064, China.
Summary
China's expressway design, using the 30th highest hourly volume (30 HV), is outdated. Analysis reveals severe traffic polarization, making the current design hourly volume (DHV) factor ineffective and causing significant congestion.
Area of Science:
- Transportation Engineering
- Traffic Flow Analysis
- Civil Engineering
Background:
- The design hourly volume (DHV) based on the 30th highest hourly volume (30 HV) is a standard in expressway design globally.
- This method has remained unchanged in China, despite significant shifts in the traffic environment.
Purpose of the Study:
- To investigate the applicability of the current DHV factor in China.
- To analyze traffic demand patterns and identify causes of expressway congestion.
Main Methods:
- Collected annual hourly traffic volume (HV) data from expressways across East, Southwest, and Northwest China.
- Analyzed HV data distribution and HV factor characteristics.
- Evaluated the typicality of the 30 HV and the DHV factor's effectiveness.
Main Results:
- Severe polarization in HV distribution was observed in China.
- The actual 30 HV factor significantly exceeds recommended values, leading to over 200 hours of inefficient travel time annually.
- The 30 HV is no longer a typical indicator, and the current DHV factor is inapplicable.
Conclusions:
- The current DHV factor based on 30 HV is unsuitable for Chinese expressways.
- Adjusting the DHV factor to 10 HV or 80 HV, depending on economic development, can mitigate congestion.
- Revising expressway design standards is crucial for addressing widespread congestion issues in China.
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