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T*P.D*M.V.2.4
(v)
For left hand splay junctions the offset d la 4.5m*
Crossroads (layout (b))
There are similarities with the design described under (a)
but the following points should be noted :
(i)
(ii)
The long axis of the island is inclined at 5 degrees
to the minor road centre line and the island is
always 3m wide*
The circular arc R1 has a radius of 11m and is
tangential to the left hand side of the island
(viewed from the minor road approach) and the centre
line of the major road. (In some cases where the
minor road is inclined to the major road at angles
between 100 degrees and 110 degrees R1 will have to
be reduced to 8m to create a suitable island*)
(iii) The circular arc R2 has a radius of 11m and is
tangential to the major road centre line and the
minor road centre line.
(iv)
(v)
(vi)
Where the minor road centre line is inclined to the
major road at angles less than 70 degrees H1 will
normally be 12m and R2 8m.
Where the minor road centre line is inclined to the
major road at angles greater than 110 degrees R1
will normally be 8m and R2 12m.
Where two splay minor roads meet at a crossroad the
minor road centre lines should be offset relative to
one another by approximately the width of one
island*