A method of economic evaluation of noise mitigation measures in urban rail transit

In addition to its many benefits, urban rail transit generates noise pollution that poses critical environmental and public health challenges. Traditional noise control strategies often rely on satisfying regulatory noise limits but do not take into account the social benefits of noise mitigation in the exposed areas. Moreover, conventional evaluation methods for railway transport infrastructure fail to provide a detailed analysis of the long-term socio-economic impact of noise reduction measures. This paper proposes a method for the economic evaluation of noise mitigation measures to enhance the sustainable development of urban rail transit, aiming to identify the most appropriate measures in terms of both cost efficiency and noise mitigation effectiveness. The main novelty lies in the combination of a single measure of life cycle cost (LCC) and monetized noise reduction to model the socio-economic impacts of the measures. The evaluation framework standardizes these impacts into measurable economic indicators, enabling direct comparisons between different measures. A case study involving a residential area adjacent to Beijing Subway Line 13 demonstrates the practical application of this approach. The cost-effectiveness of 4 m high noise barriers and rail grinding is analyzed and compared. Results show both measures have significant benefits: noise barriers incur higher initial costs but offer greater absolute economic benefits due to their superior noise reduction capabilities, and they are more suitable for densely populated areas, whereas rail grinding is recommended for extensive use in regular track maintenance due to its lower unit cost. The proposed evaluation method is verified by comparative analysis with existing methods. It provides a practical decision-making tool for urban rail noise abatement from the viewpoint of sustainability.