TY  - JOUR
PY  - 2020//
TI  - Analytical method to approximate the impact of turning on the macroscopic fundamental diagram
JO  - Transportation research record
A1  - Xu, Guanhao
A1  - Yu, Zhengyao
A1  - Gayah, Vikash V.
SP  - 933
EP  - 947
VL  - 2674
IS  - 9
N2  - Network macroscopic fundamental diagrams (MFDs) have recently been shown to exist in real-world urban traffic networks. The existence of an MFD facilitates the modeling of urban traffic network dynamics at a regional level, which can be used to identify and refine large-scale network-wide control strategies. To be useful, MFD-based modeling frameworks require an estimate of the functional form of a network's MFD. Analytical methods have been proposed to estimate a network's MFD by abstracting the network as a single ring-road or corridor and modeling the flow-density relationship on that simplified element. However, these existing methods cannot account for the impact of turning traffic, as only a single corridor is considered. This paper proposes a method to estimate a network's MFD when vehicles are allowed to turn into or out of a corridor. A two-ring abstraction is first used to analyze how turning will affect vehicle travel in a more general network, and then the model is further approximated using a single ring-road or corridor. This approximation is useful as it facilitates the application of existing variational theory-based methods (the stochastic method of cuts) to estimate the flow-density relationship on the corridor, while accounting for the stochastic nature of turning. <br><br>RESULTS of the approximation compared with a more realistic simulation that includes features that cannot be captured using variational theory--such as internal origins and destinations--suggest that this approximation works to estimate a network's MFD when turning traffic is present.<p />  <p>Language: en</p>
LA  - en
SN  - 0361-1981
UR  - http://dx.doi.org/10.1177/0361198120933274
ID  - ref1
ER  -