B-1 AGREEMENT System Generated e-Tender No ... - e-Tendering

78 Dy. Executive Engineer
2. FROMWORK FOR CONCRETE WORK :- The forms of concrete shall be of the materials as
directly by the Executive Engineer-in-charge and shall preferably be of steel or plywood,
Forms shall be of the required shape, profile and lines. Suitable devices shall be used to hold
corners, adjacent ends, edges of panel or other forms together in accurate alignment. The
forms and joints shall tight enough. Forms used for circular curved or structures of unusual
shape, petal dome etc. shall be of such a character that will result in smooth concrete surface
and exact shape. They shall be prepared such that they will not warp or distort during erection
or while placing concrete. Their design and layout shall be got approved form the Executive
Engineer-in-charge in advance.
3. ERECTION AND REMOVAL OF FORM WORK :- The centering and strutting shall be of
steel or plywood board exclusively for concreting. The design and drawing should be got
approved in advance from the Department. For minor members the Engineer-in-charge may,
at his discretion, permit use of wooden shuttering. The centering and shuttering shall be close
and tight to prevent leakage of cement slurry. The centering shall have the necessary props,
bracing and edges sufficiently strong and stable which shall not yield or displace while or after
laying of concrete. They shall be made in such way that they can be slackened and removed
gradually and slowly without distributing the concrete. Centering and shuttering shall not be
removed before the design strength is achieved.
4. MIXTURE OF CONCRETE :- Design mix concrete as well as nominal mix concrete shall be
mixed by following the provision in Standard specification at B. 6.4 unless otherwise directed
by the Engineer.
Unless otherwise agreed by the Engineer concrete shall be mixed in a batch type mixer of
such other type of mixer as the Engineer my approve.
During hot weather the Contractor shall ensure that the constituent materials are sufficiently
cool to prevent the concrete from stiffening in the intervals between its discharge from the
mixer and its final position.
5. TRANSPORTATION, PLACING AND COMPACTION OF CONCRETE :- The method of
transportation placing and compaction of concrete shall be followed as per section B.6.6, 6.7
and 6.8 of Standard Specification unless otherwise directed by the Engineer. The compaction
shall be done with surface float vibrators for slabs and with pin vibrators for columns and
beams. Vibrators of adequate vibrating capacity shall be employed for all types of works.
6. CURING :- Curing shall be done by following provision of Section B.6.9 of Standard
Specification and as directed by the Engineer.
7. WORKING IN EXTREME WEATHER : During windy weather sufficient protection shall be
provided to prevent the cement from being blown away during the process of proportioning
and mixing. During wet weather, the concrete shall be adequately protected as soon as it is
placed in position.
No concreting shall be carried out during period of continuous heavy rains unless, it is
completely covered during mixing, transporting and placing, In extreme hot weather,
concreting shall be restricted to morning and evenings The time between mixing and placing
of concrete shall be kept to the minimum and formwork shall be cooled by sprinkling with
water.
8. FINISHING : Finishing work shall comply with requirement of section B.6.10 of Standard
Specification unless otherwise specified herein below :
Immediately on removal of forms, the R.C.C. work shall be examined by the Engineer before
any defects are made good.
a) The work that has sagged or contains honey combing to an extent detrimental to
structural safety or architectural concept shall be rejected.
b) Surface defects of a minor nature shall be rectified generally as indicated below by
the contractor.
Signature of Contractor No. Of Corrections Executive Engineer