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a b s t r a c t MAXBAND and MULTIBAND are two well-recognized methods for arterial signal control. In this paper, an Asymmetrical Multi-BAND (AM-BAND) model is developed by relaxing the symmetrical progression band requirement in MULTIBAND. Such a relaxation allows the AM-BAND model to better utilize the available green times in each direction and to provide additional opportunities for vehicular progression. Similar to MULTIBAND, the proposed AM-BAND model is formulated as a mixed-integer linear program. However, in AM-BAND the green bands in each directional section of the arterials do not have to be symmetrical with respect to the progression line. The performance of the AM-BAND model is evaluated for two arterial network data using the AIMSUN microscopic traffic simulation tool. The optimal signal coordination plans are computed by the IBM CPLEX Optimization Studio and compared with signal timing plans generated by AM-BAND, MULTIBAND, and MAXBAND. Simulation results indicate that the traffic signal coordination plans generated by AM-BAND can provide significant benefits compared to those generated by MAXBAND and MULTIBAND.Published by Elsevier Ltd.

OD-BAND is a progression optimization model that can provide dedicated progression bands for major origin–destination (O-D) flows in an arterial network. The model is an extension of the well-known MAXBAND model and is solved by advanced mathematical programming optimization software. In this paper, the original OD-BAND model is extended in a number of important ways: ( a) the mathematical formulation is generalized to model all possible O-D flows in an arterial; ( b) phase sequence optimization is included for all intersections along the arterial; and ( c) the bandwidths are weighted by the number of street segments that they traverse and their traffic volumes. It is shown that this formulation can provide suitable progression bands for all major O-D flows, including both through bands and cross bands. Simulation results demonstrated that OD-BAND compared favorably with existing arterial traffic signal coordination models MAXBAND and MULTIBAND and could be used as a valuable tool in signal control software. In particular, this approach is most suitable for integrated traffic signal coordination and route guidance in an environment of connected vehicles in which connected vehicles and crowd-sourced data can be used to derive detailed and accurate O-D information. Progression bands can then be established for each major O-D flow, and route guidance can be provided to vehicles to travel within those bands with minimum delay and fuel consumption.

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This paper summarizes the result of a study investigating the flexural behavior of concrete beams reinforced with high-strength prestressing strands. Thirteen concrete beams reinforced with either conventional reinforcing bars or high-strength strands were fabricated and load tested in the experimental part of the study. No distinct difference was detected between the experimentally obtained cracking patterns of the two groups of beams. For the same reinforcement amount, beams reinforced with high-strength strands exhibited slightly smaller service stiffness than those reinforced with conventional reinforcing bars. A comparison of the measured and numerically predicted response of beam specimens indicated that the cracking load, peak load, and the deformation capacity of concrete beams can be accurately determined by a sectional analysis procedure for both types of reinforcement. The level of ductility present in concrete beams reinforced with high-strength strands is evaluated using the parameter called “displacement deformability ratio.” Using the numerically determined maximum reinforcement limits for concrete beams reinforced with high-strength strands, an expression was proposed to be used at the design stage.