07/1841 - Response to Information Request [As Published] · 132007.1841

 

4.0

TRAFFIC IMPACT

4.1. INTERSECTION OPERATIONS

The capacity assessment of intersections was carried out using the SIDRA
INTERSECTION 3.1 traffic modelling software. This is an advanced micro-
analytical traffic evaluation tool that evaluates the capacity of the intersections. It
provides thorough operational analysis of the intersections.

(i) Connector Road / Loop Road Roundabout
For the purpose of capacity analysis the roundabout was designed with 2

circulating lanes having width of 10m total and a central island with diameter of
15m. The layout of the roundabout has been illustrated in the Figure 4.1.

 

Connector Road (N)

 

Loop Road (E)

 

 

 

 

Figure 4.1 — Proposed Loop Road / Connector Road Roundabout

 

When considering roundabouts, a Degree of Saturation (DOS), (which is the ratio
of flow to capacity) greater than 85% is considered over capacity. Above this
value, performance deteriorates quickly and operation becomes poor.

The analysis shows that the roundabout works very well as the key performance
indicators are according to DMR standards. The maximum queue forming on the
Southern Loop Road Approach is 25m and would not affect the operation of Loop
Road / E5 & B3 Access Roundabout because two roundabouts are about 64m
apart from centre to centre. The maximum queue forming on the Connector Road
Approach is 19m and would not affect the operation of Roundabout on Eenie
Creek Road because this roundabout is a distance of 65m from Eenie Creek
Road.

 

4686-1

January 2008 Vem BURCHILL VDM