Optimal frequency setting of metro services in the age of COVID-19 distancing measures

Abstract

Public transport is one of the most disrupted sectors of the COVID-19 pandemic with reported ridership drops up to 90% in majorly affected countries. As many government authorities strive to partially resume activities, public transport operators are in an urgent need for models that can evaluate the impact of different social distancing policies on operational and passenger-related costs. In this study, we introduce a mixed-integer quadratic programming model for the redesign of public transport services considering the operational, passenger, and revenue loss-related costs by evaluating the effects of different social distancing policies. Our model is applied at the metro network of Washington DC and provides optimal redistribution of vehicles across lines for different social distancing scenarios. This model can be used as a decision support tool by other policymakers and public transport operators that are in need of evaluating the costs related to the implementation of different social distancing policies.

A COVID-19 Public Transport Frequency Setting Model That Includes Short-Turning Options

“…Maintaining social distancing can be achieved by means of a combination of measures. At the strategic level, decisions about the modification of public transport stops (e.g., stop closures) have been implemented [14]. Transport for London and Washington Metro are just two of the public transport authorities/service providers that decided to close specific public transport stations to avoid overcrowding beyond the COVID-19 capacity limit.…”

“…Furthermore, closely related to this study is the work of Gkiotsalitis and Cats [14]. Gkiotsalitis and Cats [14] proposed a network-wide frequency setting model considering social distancing to find the optimal allocation of vehicles over the lines and the corresponding headways. The objective is to minimize the revenue loss while also considering the passengers' average waiting time.…”

“…In this study, the network-wide frequency model of Gkiotsalitis and Cats [14] will be adapted and extended. In this extension, buses will be scheduled on short-turning sublines in order to reduce the operational costs while meeting the pandemic-imposed capacity limitations.…”

“…This hour was selected because the passenger demand is higher and this might lead to passengers that cannot be accommodated due to the pandemic-imposed capacity. As a baseline, the model of [14] will be considered. The baseline model is a frequency setting model that sets the frequencies of public transport lines while considering the pandemic-imposed capacity limitations.…”

“…After applying the baseline model of [14], including the different user types and boarding priority (Equation ( 11)), to the data of 2 March 2020, the following results were obtained:…”