ENTRY AND CIRCULATING FLOW RELATIONSHIP AT A ROUNDABOUT
DOI:
https://doi.org/10.11113/mjce.v16.15661Keywords:
Roundabout, Weaving Concept, Circulating Flow, Entry Flow.Abstract
This study examined the two formulas stated in the Arahan Teknik (J) 11/87 of the
Malaysian Public Work Department to estimate the capacity of small and conventional
roundabouts. Field survey, which cover the roundabout inventories, and vehicle classification were
carried out. Vehicle classification survey indicates lower entry flows at the single lane entries
compared to the multilane entries for both morning and evening peak hours. Statistical analysis
was used to identify the correlation between the circulating flows, entry flows and the entry width.
Results showed that the capacity obtained from the weaving concept was generally higher than the
regression equations for the single and multi entries. The difference between these results may be
due to the regression equations that consider the interaction between the entry and circulating flow
and the geometric parameters, while the Arahan Teknik (J) 11/87 only address the geometric
parameter. The entry flows for both single and multilane entries were highly dependent on the
circulating flows.
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