Achieving carbon efficiency in construction & maintenance of railway turnouts, crossovers and diamonds

Railway turnouts, crossovers, and diamonds are special track systems used to divert a train from a particular direction or a particular track onto other directions or other tracks. It is a structural grillage system that consists of steel rails, points, crossings, steel plates, rubber pads, insulators, fasteners, screw spikes, beam bearers (either timber, polymer, steel or concrete), ballast and formation. Usually under dynamic and high-intensity impact loading conditions, structural components of the turnout tend to have relatively short lives compared with those of ordinary open railway tracks, resulting in frequent turnout re-construction and maintenance (ranging from every 10 to 20 years). Such the activities emit greenhouse gas (GHG) that increasing air pollution and contributing to climate change. Although railway operation is the most sustainable and carbon-efficient mode of transport, its considerable construction and maintenance often produce large amount of greenhouse gas. This study aims at developing a practical guideline to achieve carbon efficiency in the construction and maintenance of railway turnout. It involves significant field-based surveys and monitoring of the critical and detailed data of CO2 emissions from each task, process and activity across multi functions. The outcome of this study provides an alternative planning and decision-making tool taking into account environmental benefits and risk management for railway engineers.