ABSTRACT
Singapore Circle Line (CCL) project is an on-going project undertaken by Land Transport Authority (LTA) to fulfill the increasing transport needs of the populous nation, and at the same time achieving LTA’s vision of developing a people centric public transport system.
In this CCL project, all 29 underground stations will be equipped with Platform Screen Doors (PSD). The PSD facade runs the full length of each platform bound, which is approximately 70m long. 12 PSD doorways are provided at each platform and aligned with each doorway of the 3-Car passenger train.
PSD serves many purposes, such as the isolation of passengers from the tracks and the prevention people and objects from falling onto the tracks. As Singapore is a tropical country, PSD also serves another key function of encapsulating the station box, thereby allowing efficient and cost-effective management of air-condition within the underground stations.
PSD systems require precise and meticulous installation due to two main reasons. Firstly, the PSD façade is designed to minimize the step gap between the platform edge and the train door threshold plates. This means that the PSD structure has to be situated near to the Kinematic Envelope of the train. Therefore, the PSD doors have to be installed precisely to design, with controlled tolerances. Secondly, as the PSD shares the same electrical potential to the running rails, it is crucial to ensure the PSD is at all times kept electrically isolated from the station civil structural, to mitigate touch potential hazards to the commuters.
Given the technical requirements, the success of the PSD project hinges heavily on close and tedious coordination with the line wide CCL civil contractors to fit a standard PSD design into varying station architectural layouts. As such, on-site complications are inevitable and are occurring sporadically as the project progresses. Hence, the PSD system construction requires concerted coordination efforts to ensure that the designed specification is met throughout the construction phase.
Therefore, this paper discusses in brief the various issues and challenges that are faced by the PSD engineers along the course of the circle line PSD construction and how these problems are being resolved and mitigated.
Keywords: Touch voltage, Architectural finishes, Cast in channels.
