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Conventional geometric design methods for pre-signal systems usually use the expected traffic demand, which may obtain a short sorting area distance and lead to frequent queue spillbacks due to stochastic traffic arrivals. On the other hand, if one selects a longer sorting area distance, the geometric design will suffer from low spatial utilization with higher delay and lower capacity. In this paper, we propose a geometric design method for intersections with pre-signal systems using a phase swap strategy. The geometric design can balance the desire of storing more vehicles to prevent spillbacks and improve the spatial utilization of the road. We model the traffic dynamic within the pre-signal system using queue theory and shockwave theory to determine the furthest point a queue can reach. The length of the pre-signal system should be short enough to improve spatial utilization but longer than the furthest point of the queue to prevent queue spillback. The effectiveness of the pre-signal system is evaluated by the VISSIM Signal Control Application Programming Interfaces (SCAPI). The results indicate that the proposed design plan increases the spatial utilization of the pre-signal system by 7.5% while maintaining a similar delay, queue length and ratio of flow to saturation flow.

The design of a bicycle lane's cross-section has a significant influence on the riding behaviours of cyclists. Wider bicycle lanes can encourage users of electric bicycles (e-bikes) to ride within the lane by providing the necessary riding space, which will improve the safety and efficiency of overall multi-level heterogeneous traffic flow. An empirical cross-section design was obtained based on field observations of the riding characteristics of e-bike users at four road sections in Xi'an, China. Vehicle widths, the gaps between vehicles and additional security gaps were considered in order to optimise the design of the cross-section. The results indicate that users of e-bikes within heterogeneous traffic flow need more lateral space for safe riding. The cross-section of bicycle lanes should allow the completion of overtaking manoeuvres, and the results suggest the cross-section needs to be wider than 3 m and no less than 2·6 m. The recommendations of cross-sections with different physical separations were carefully calibrated in order to meet riding requirements. The findings of this study provide reference material for the design of bicycle lanes with consideration of e-bikes.

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