Managing traffic during oversaturated conditions is a challenge for practitioners due to the lack of adequate optimization tools for addressing such situations. Unlike under-saturated conditions, operation of traffic signal systems during congestion requires careful consideration and analysis of the underlying causes of the congestion before developing mitigation strategies. This paper presents an application of a new oversaturation timing strategy (OTS) in a congested arterial network. The OTS employs the principles of oversaturation timing (i.e., prevent spillback into upstream intersections and prevent starvation at downstream intersections in cycle length selection, splits allocations, and offset design along with critical routes protection. Microscopic simulation results of the arterial test case revealed that traffic control strategies developed using the proposed framework led to significant improvement of system performance when compared to signal control strategies designed for operations in under-saturated conditions. Each of the generated control plans includes series of timing plans with different control objectives. These control plans successfully manage the queues along the network links. The developed control plans apply both internal metering by allocating queues on links with extra reserve capacities, and external metering by holding traffic outside the network preventing demand loading on the network from reaching critical levels. It also revealed that applying capacity maximization on early stage would provide extra reserve capacities to the critical routes unlike delay minimization control that balances the queues formations on all network links.
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