Page 115 - Proceeding of Atrans Young Researcher's Forum 2019_Neat

“Transportation for A Better Life:
Smart Mobility for Now and Then”

23 August 2019, Bangkok, Thailand

Travel behavior change under adverse weather conditions
– An essential study for formulating “active” traffic management strategies
Topic number: 09 Paper Identification number: AYRF2019-016
1
Thi Thanh Huong NGUYEN , Anh Tuan VU 2

1 Department of Urban Transport Planning and Management, Faculty of Transport Economics
University of Transports and Communication, Campus in Ho Chi Minh City
Telephone 0084-9-88-72-72-09
E-mail: ntthanhhuong@utc2.edu.vn

2 Vietnamese-German Transport Research Centre (VGTRC), Vietnamese-German University (VGU)
E-mail: drtuan.va@vgtrc.vgu.edu.vn

Abstract
In major cities, road flooding caused by heavy rain and/or high tidal rise frequently happen and cause
road traffic congestions and accidents. To help design effective traffic management measures for Ho Chi
Minh City, this paper focuses on a survey of the people’s travel behavior changes under the adverse weather
conditions. This paper analyzes mode choice behavior in different weather conditions, with population
groups, on travel purposes and travel distances to support the formulation of weather responsive traffic
management measures. Revealed and stated adaptation surveys are carried out with 400 respondents and 100
respondents, respectively. Typical patterns of travel behavior changes and influential factors were analyzed
based on the surveyed data and by using the Pearson Chi-square Independence Test. While trip cancelation,
delayed departure, waiting for resuming of trip, route change, and destination change are significant, mode
change is very modest. A road flood causes the changes more strongly than a heavy rain. The major patterns
of mode change are shifts from motorcycle to car or taxi, accounted nearly half of mode changes, thus causing
severer traffic congestions. Besides, the stated adaptation survey and mode choice modeling show travel time,
travel cost, gender, income, specific jobs, motorcycle ownership, bus ticket holding, provision of weather
information prior to the trip are significant factors to mode choice decision under bad weather conditions.

Keywords: Adverse weather, Road flooding, Travel behavior, Mode choice, Ho Chi Minh City

1. General Introduction conditions than private cars and public transport.
Like other major cities in Southeast Asia, The city has been
Ho Chi Minh City (HCMC) has been suffering from applying a
heavy road flooding caused by heavy rainfalls and/or number of
tidal rise. It has caused economic loss due to measures to
interrupted freight transport, increased traffic mitigate the
congestion and traffic accidents in the city [8]. Ho impacts of
Chi Minh City is the biggest city in Vietnam with adverse weather
nearly 9 million populations. The city’s transport conditions, but
system is heavily dependent on private vehicles, these are rather Fig. 1 A road under flooding in
especially motorcycle. Road congestions and “passive”. VOV
accidents are serious problems and become even Traffic Ho Chi Minh City
more serious under urban flood conditions. There are Information Channel diffuses traffic warning
about 60-120 heavy rainfalls and tidal rises each information but only car drivers can access it. High-
year, resulting in serious flooding in the city. Given capacity hydraulic pump system would help reduce
the high motorization level and underdeveloped road flooding at some locations but not all the city area.
infrastructure, the impacts of adverse weather Road congestions happen right after a heavy rain as
conditions become even more serious since authorities and road users respond passively with
motorcycles are more vulnerable to extreme weather incidents during and after the heavy rain.
It is urgent to formulate and implement a with the impacts of heavy rain and road flooding for
package of traffic management measures to cope the city. This work requires an understanding of

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