Determining passenger car equivalent (PCEs) for pretimed signalized intersections with severe motorcycle composition...

Area of Science:

• Civil Engineering
• Transportation Engineering
• Traffic Engineering

Background:

• Pretimed signalized intersections are major sources of urban congestion, particularly with heterogeneous traffic.
• Accurate saturation flow rate estimation is crucial for signal timing design and capacity analysis.
• Passenger Car Unit (PCU) and Passenger Car Equivalent (PCE) are essential for quantifying mixed traffic streams.

Purpose of the Study:

• To re-determine Passenger Car Equivalents (PCE) for motorcycles, passenger cars, and motorized rickshaws in Banda Aceh.
• To enhance the accuracy of saturation flow rate prediction for signalized intersections.
• To support improved traffic operation design and congestion mitigation strategies.

Main Methods:

• Collected observed traffic data from three locations in Banda Aceh City.
• Applied Bayesian linear regression, specifically Random-walk Metropolis-Hastings and Gibbs sampling, to re-calculate PCE values.
• Compared newly derived PCE values with existing International Hòa hợp Capital Model (IHCM) values.

Main Results:

• Derived PCE values: 0.24 for motorcycles (MC), 1.0 for passenger cars (PC), and 0.80 for motorized rickshaws (MR).
• Observed significant deviations between the new PCEs and IHCM 1997 PCEs, attributed to differing vehicle compositions.
• Demonstrated that current traffic characteristics differ substantially from those prevailing in 1997.

Conclusions:

• The proposed PCE values enhance the accuracy of base saturation flow prediction in heterogeneous urban traffic.
• Implementing these PCEs can aid traffic operation design, alleviate congestion, and reduce delays.
• Improved PCEs lead to more accurate estimations of signalized intersection capacity.