Summary: | Shared space is an innovative streetscape design which seeks minimum separation between vehicle traffic and pedestrians. Urban design is moving towards space sharing as a means of increasing the community texture of street surroundings. Its unique features aim to balance priorities and allow cars and pedestrians to co-exist harmoniously without the need to dictate behaviour. There is, however, a need for a simulation tool to model future shared space schemes and to help judge if they might represent suitable alternatives to traditional street layouts. This thesis presents a microscopic mathematical model to simulate pedestrians and 4-wheeled motorised vehicles in shared space schemes. The complete development of the model is addressed: mathematical formulation of three interrelated layers based on the Social Force Model (SFM), software implementation, calibration and validation using the case studies from New Road (Brighton) and Exhibition Road (London). Microscopic pedestrian, vehicle and mixed traffic models are reviewed and evaluated with respect to their ability to reproduce behavioural phenomena, resulting in the SFM being adopted as the most suitable basis for this thesis. The behavioural patterns of shared space users are analysed to identify specific manoeuvres that need consideration. These patterns are realised in a three-layer model: The first layer introduces the flood fill algorithm to define intermediate destinations for agent's path around obstacles to the final destination. The second layer explains how the SFM is modified for pedestrians and vehicles. The third layer describes conflict avoidance with minimal change of speed and direction. The new mathematical model is calibrated and validated according to defined performance indicators using real data from the two case study sites. The results show that this model is suitable to simulate shared space users but that the physical parameters depend on how a shared space scheme is realised compared to the original philosophy. The achievements of this thesis can be beneficial to urban planners and councils considering the implementation of a new shared space scheme.
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