Hello Sir,

Mass concrete means the cement concrete used for constructions of dams, massive structure and raft slab and beam in foundation of heavy structure. There should be rigid/strict control on concrete work with view to ensure durability, strength, impermeability and uniformity. In big projects the detail specification are issued separately for individual project according to the site requirement and other situation at site of work. As mass concrete is use in important project having heavy load and different types of stresses. Any small deviation in specifications or any irregularity omitted or committed may be the cause of failure of the structure.

Precautions

1 Cement used in the project should be Portland cement of 43 grade IS no 8112 or 53 grade IS no: 12269 and it should from fresh supply.
2 Storage of cement should be in weatherproof store and shall be constructed such so that there will be no dead storage.
3 The cement should be used within 30 days from the supply taken from factory
4 Accelerators shall be used as admixture for increasing strength of the concrete at early ages.
5 Air entry agent used for improving the quality and workability of the concrete.
6 Water use shall confirm the specification as per IS 3025.
7 Coarse aggregate consisting of  natural occurring stones gravel without being broken and shall be from 6 inch to ¾ inch grading size.
8 Test for soundness , strength, resistance to abrasion, volume change, particle shape specific, gravity, gradation and contaminating substances should be investigated in lab before the use.
9 Fine aggregate should confirm the test requirement such as soundness, organic impurities etc and having fineness modulus 3.5 to 4.2.
10 Wait batching equipment should be used for mixing the concrete mix.
11 All the mix should be mechanical mix using concrete mixer, truck mixer, agitators, charging operations, maxing operation, discharging operation machinery etc.
12 At the end of the each mix/ run and before again placing new mix all hardened concrete shall be removed.
13 Consolidate the cement concrete by vibrators and the slump for mass concrete should be low having value 25-75 mm.
14 Construction joints should be given in concrete work after each stoppage of work.
15 Contraction joints should be given where required according to the need of the structure.
16 Concrete work should be suspended during excessively hot, cold or rainy weather
17 Finishing of the concrete surface should be done as desired for mass concrete.
18 Curing of all concrete should be done at least for 28 days