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The bilateral Bus Rapid Transit (BRT) system is a kind of BRT system in which the stops are located in the middle of the transit lane. By simultaneously serving transit lines in opposite directions, it is particularly designed to save space resources and enhance service quality. To improve the operational efficiency of the bilateral BRT, this paper optimizes the operational performance of bilateral BRT with elastic demand. The objective is to minimize the generalized time cost per passenger of the system by jointly optimizing the headway and number of stops of bilateral BRT. The cost includes the agency operating and user travel. The optimal design model is formulated as a mixed-integer program and solved using a fuzzy analytic hierarchy process (FAHP) and a genetic algorithm (GA). We conduct a case study and sensitivity analysis to show the effectiveness and reliability of the proposed approach. We conclude that the optimized minimum generalized cost per passenger is lower than the actual case for all demand levels, especially at off-peak hours, by about 22.5%. In addition, we find that the weights of agency and user costs have the most significant impact on headway, whereas the influence of walking, vehicle speed, and route length is minimal. In contrast, the optimal number of BRT stops is mostly influenced by the route length, and walking speed has essentially no effect on the optimal number of stops. Finally, we find that the generalized cost per passenger at peak hours is 10% to 15% smaller than at off-peak hours in various scenarios. [ABSTRACT FROM AUTHOR]

The uneven distribution of travel demand is incredibly commonplace in cities, but insufficient attention has been paid to this problem. In this paper, we explore the impact of the uneven distribution of travel demand on an accessible network. A model with a sparse and dense mixed grid transit network based on an uneven distribution of travel demand is proposed to provide a high-performance bus service. The transit network was composed of two parts: a dense grid network in the downtown area and a sparse grid network in the periphery. The objective function of the model included agency cost and passenger cost, where the decision variables were the downtown-to-city ratio, the downtown headway, stop spacing (line spacing), and ratio of the periphery headway to the downtown headway. This study validated the proposed model using the demands of San Francisco. The concentrated spatial demand resulted in a lower total cost, whereas the varying travel demand must be controlled within an appropriate range to maintain the bus performance. The stable bus lines and stops with a variable timetable of the proposed model are profitable for fast-growing cities. [ABSTRACT FROM AUTHOR]

• Grid transit network is adopted in few metropolitan areas with an orthogonal scheme. • Normally, this PT layout is not adopted at all in non-metropolitan contexts. • A GIS-based model tests its suitability in the Italian city of Turin. • Results in terms of agency costs and users' travel times reveal its competitiveness. • Some transport and morphological features are a prerequisite for its implementation. This paper deals with grid transit network schemes and their specific features: orthogonal main routes that do not overlap, increased transit frequency, and distance between bus stops in interchange areas to be optimized. So far, this solution has been successfully adopted in metropolitan areas with orthogonal urban shapes (as shown by the description in Section 2). The aim of this paper is to discuss the extension of such systems into cities with less than one million inhabitants. A method to evaluate the performance of these schemes is proposed, based on the reduction of travel times for users and on the decrease of travel costs for the transport agency, with the constraint of not reducing the overall capacity. With the support of a GIS-based model, the method is applied to the case study of Turin (Italy), showing that the introduction of the grid network results in an improvement of the service, with a reduction of 16 bus routes. Compared to the current condition, this grants a reduction of both operational costs (−687€/peak hour and −232€/off-peak hour, equal to −0.7% and −0.3%) and, mostly, travel times (636 h and 316 h saved by users during peak and off-peak hours, equal to −2.4% and −2.7%), thus confirming the potential usefulness of this system in non-metropolitan contexts characterized by orthogonal schemes, and giving local transport policy-makers an additional perspective. [ABSTRACT FROM AUTHOR]