Volume-IF - JantERmantER

DCPL-K4A02
impair the strength of concrete or cause stains or marks on the finished
surface. Where there are chances of these fixtures being embedded, only
mild steel or concrete of adequate strength shall be used.
Alternatively, except in case of water retaining structures through rods
and the tie bolts shall be sleeved with PVC conduits to allow retraction of
the ties on removal of the shutters. Where required, the annulus of the
conduits will be filled with expanding mortar to seal the void. Bolts
passing completely through liquid retaining walls/slabs for the purpose of
securing and aligning the formwork shall not be used.
The formwork shall be such as to ensure a smooth uniform surface free
from honeycombs, air bubbles, bulges, fins and other blemishes. Any
blemish or defect found on the surface of the concrete must be brought to
the notice of the Engineer immediately and rectified as directed by him.
For exposed interior and exterior concrete surfaces of beams, columns and
wall, plywood or other approved form shall be thoroughly cleaned and tied
together with approved corrosion- resistant devices. Rigid care shall be
exercised in ensuring that all column forms are plumb and true and
thoroughly cross braced to keep them so. All floor and beam centering
shall be crowned not less than 8 mm in all directions for every 5 metres
span.Unless specifically described on the drawings or elsewhere to the
contrary, bevelled forms 25 mm by 25 mm shall be fixed in the form-work
at all corners to provide chamfering of the finished concrete edges. The
formwork should lap and be secured sufficiently at the lift joints to prevent
bulges and offsets.
Temporary openings for cleaning, inspection and for pouring concrete shall
be provided at the base of vertical forms and at other places, where they
are necessary and as may be directed by the Engineer. The temporary
openings shall be so formed that they can be conveniently closed when
required, during pouring operations without leaving any mark on the
concrete.
3.20.2 Cleaning and Treatment of Forms
All parts of the forms shall be thoroughly cleaned of old concrete, wood
shavings , saw dust, dirt and dust sticking to them before they are fixed in
position. All rubbish, loose concrete, chippings, shavings, saw dust etc.
shall be scrupulously removed from the interior of the forms before
concrete is poured. Compressed air jet and/or water jet along with wire
brushes, brooms etc. shall be used for cleaning. The inside surface of the
formwork shall be treated with approved non-staining oil based shutter
release agent like "Separol/Sika form oil/ Siparol Concentrate" before it is
placed in position. Care shall be taken that oil or other compound does
not come in contact with reinforcing steel or construction joint surfaces.
(PCA.774.S034sca2) V.II-D2/S-III : 29