Savithramma R M et al. / IJETT, 70(8), 359-374, 2022
360
cost to the environment. Under these circumstances, the
traffic and transport studies support the development of
project proposals focussing on transportation management
in urban areas. Limited studies have been carried out for
traffic characterization at intersections in the urban area
(Pothula Sanyasi Naidu et al., 2015)(Shen and Wang, 2018).
At the same time, a review of existing studies on
intersection traffic modelling is presented (Pegu and Nath
2017).
Operations of signalized intersections are a part of the
transportation management system. Junctions are the critical
segments of the urban road network, while the delay is the
prime concern of operational strategies implemented at the
intersection. In this article, an attempt has been made to
study the signalized intersections to assess their level of
service. With this perspective, two junctions from
Tumakuru, namely the Shivakumara Swamiji circle and the
Town Hall circle, have been chosen for the current study.
Tumakuru is a tier-2 city in India's southern state
(Karnataka). The necessary data for the study is collected
through videography. The parameters such as ratios of
volume-to-capacity, traffic volume, traffic composition,
saturation movements, signal configuration, delay, fuel
consumption and emissions are analyzed to explore the
operation level at selected city intersections.
In North America, the HCM (Highway Capacity
Manual) TRB 2000 (Transportation Research Board,
National Research Council, Washington, DC 2000) is the
most widely used method for signalized intersections
analysis. The intersection performance is defined in terms of
mean delay. The delay is mapped against predefined service
levels ranging from A to F, where 'A' represents the best
Level of Service (LoS), and 'F' designates the worst service
level operations. And the delay is computed as a function of
many other factors, including signal configurations,
temporal traffic variations, driver behaviour and
environmental conditions. The analysis strategies defined by
HCM are focused on uniform traffic composition. But the
traffic conditions in India are highly heterogeneous. Hence,
the analysis guidelines described in Indian Road Congress
(IRC) (Indian Roads Congress 1990) and Indo-HCM (Year,
Project, and Delhi 2010) are adopted in Indian scenarios.
The forthcoming sections of the article are laid as
follows; the next section presents the available studies
concerned with the current study. The area selected for the
current study is introduced in section 3. The preliminary
statistical analysis conducted over signal operations and the
data collection concerning traffic at selected intersections
are presented in sections 4 and 5, respectively. The results
of variability analysis concerned with different parameters
are presented in section 6, and the corresponding
observations and probable solutions are discussed in section
7. Finally, the paper concludes with the report of the
proposed study.
2. Literature
By identifying the delay variability, more reliable
traffic signal configurations can be estimated to improve the
service level (Transportation Research Board, National
Research Council, Washington, DC 2000). Therefore, many
researchers worldwide have presented studies on
intersection operations and traffic conditions in specific
regions. The analysis of signalized intersections in Waterloo
and Kitchener cities of Canada is presented in (Hellinga and
Abdy 2008) with the objective of day-to-day peak-hour
traffic volume variability implications on delay. The authors
(Darma and Karim 2005) researched to determine the set of
components (variables) of the HCM delay model that
influences control delay using the capacity softwares
Transyt-7F and SIDRA.
The research is in progress to develop advanced models
for delay estimation. In this connection, many authors
worldwide have already presented the models. Different
analytical models (Fu and Hellinga 2000) (Akgungor and
Bullen 2007) (Chen et al. 2013) (Fawaz and El Khoury
2016) were presented to estimate delay. In contrast, the
studies including (Amrutsamanvar and Arkatkar 2018) and
(Yesufu et al. 2019), investigated the contribution of delay
at signalized intersections on overall travel time variability
along the route. The variance of overall delay at the
signalized intersection is estimated by (Fu and Hellinga
2000) based on delay evolution patterns in oversaturated
and undersaturated traffic situations. But, (Akgungor and
Bullen 2007) consider the traffic flow variations to compute
the delay. The model involves a delay parameter k,
expressed as a function of the degree of saturation. The
authors have proved that the proposed model performs well
in all expected traffic conditions.
Delay estimation at the pre-timed signal-operated
intersection is presented in (Chen et al. 2013) by
considering traffic arrival distributions using traditional
cumulative curves. A uniform control delay is modelled for
undersaturated intersections (Fawaz and El Khoury 2016).
The delay model (Webster 1958) proposed is appropriate for
homogeneous traffic with lane-adhered traffic situations.
Hence, its modified versions were presented by (Hoque and
Imran 2007) (Minh et al., 2010) (Preethi, Varghese, and
Ashalatha 2016) (and Saha, Chandra, and Ghosh 2017) to
suit the uniform traffic conditions in India.
A comparison of various delay models like
deterministic queuing, shock wave theory-based, Webster,
HCM, Australian Capacity Guide, etc. has been presented
(Dion, Rakha, and Kang 2004). The delay estimates were
analyzed under high and low traffic conditions and observed
that all models work better in case of low traffic demand
while showing differences in case of saturated conditions.
Performance of the traffic signal control system is expressed
in terms of delay encountered by each vehicle in a waiting