BASEMENT DRAINS SLOPE
MARKING
Basement
drain slope marking is done to assure that the water in the drains do not
stop at any point, after the drains
are constructed. This marking
can be done for excavation and PCC laying.
Procedure:
·
The alignment of the
drain should be as per the M&E drawings
which will give the centerline.
·
Drive reinforcement rods
at Ms. to 1 Om intervals from the starting point of the drain,
all along its layout.
·
On the rod
that
is fixed at the start
of the drain, a paint mark is made at
a height of 1 m (A) from the
ground level.
·
This mark is transferred to the
next rod using a tube
level (B). Assuming, that the length of a drain is 1 Om
and
a slope of 1: 100 has
been prescribed, a mark C is made
on the second
rod at a distance of 1 OO mm, below the
previously made mark. (1 OO
mm is got by applying
1: 100 slope over a
length of 1 Om).
·
A string line is tied between the first and the second rod, connecting the points A and c.
·
Now as the
excavation is being done, at any point of time, the distance
between the thread and
the bottom of the drain to be
reached should be equal
to
'h'
all along the drain.
·
The same procedure
can be followed for maintaining
the top of PCC
at the
required slope.
