GAIL (India) Limited
GAIL (India) Limited GAIL (India) Limited
193.17.2 Aggregates3.18 Water3.18.1 GeneralFor both design mix concrete and nominal mix concrete, the aggregates,(coarse and fine) shall bebatched by weight.In particular cases, or where weight-batching is not possible, proportioning by volume batching may beallowed by the aggregates throughout the period of construction. For this purpose, the Contractor shallsubmit to the Engineer sufficient data indicating the weight/volume relationship of the aggregates shallbe made by the Contractor to the satisfaction of the Engineer. Where aggregates are moist and volumebatching is adopted, allowance shall be bulking in accordance with IS (Part III).Suitable adjustments shall be made for the variation in the weight of aggregates due to variation in theirmoisture contents.Water may be measured either by weight or by volume. When measured by volume, it shall be by wellcalibrated conical shaped jar or vessel or from a calibrated tank filled to the mixer.3.18.2 Adjustment of Water Due to Moisture Contents in Coarse and Fine AggregatesIt is very important to maintain the water cement ratio constant at its correct value. For the correctdetermination of the amount of water to be added in the concrete mix, to maintain the water cementratio constant, the amount of moisture content in both coarse and fine aggregates shall be taken intoconsideration, be checked as frequently as possible, the frequency for a given job being determined bythe Engineer according to weather condition.3.18.3 Determination of Moisture Content in the AggregatesDetermination of moisture content in the aggregates shall be according to IS 2386 (Part-III). Wheretests are not conducted, the amount of surface water may be estimated from the following table:3.18.4 AdmixturesAggregatesSurface water carried by Aggregates% by weight l/m3Very wet sand 7.50 120Moderately wet sand 5.00 80Moist Sand 2.50 40Moist gravel stone chips * 1.25-2.5 20-40• coarser the aggregate, less the water it will carryAny solid admixture, to be added, shall be measured by weight, but liquid or semi-liquid admixturemay be measured by weight or volume.The Bidder shall indicate the brand name, the Manufacturer and the properties of any admixture to beused for the concrete as per Bill of Quantity items or on his own initiative.
203.18.5 Accuracy of BatchingThe accuracy of batching shall be within the following tolerance:1 Cement within + 2% by weight2 Aggregate within + 5% by weight3 Water within + 0.5% by weight.3.19 Mixing of Concrete3.19.1 Machine MixingConcrete shall always be mixed in mechanical mixer. Water shall not, normally, be charged into thedrum of the mixer until all other ingredients are already in the drum and mixed for at least one minute.Mixing shall be continued until there is uniform distribution of materials and the mass is uniform incolour and consistency. The mixing time from the time of adding water shall be in accordance with IS1791, but in no case less than 2 minutes or at least 40 revolutions.3.19.2 Hand MixingWhen hand mixing is permitted by the Engineer, it shall be carried out on a water tight platform andcare shall be taken to ensure that mixing is continued until the mass is uniform in colour andconsistency. In case, of hand mixing, 10% extra cement shall be added to each batch at no extra cost toGAIL (INDIA) LTD.,3.20 Transportation of ConcreteConcrete shall be transported from the place of mixing to the place of placing concrete as rapidly aspracticable by any means, which will prevent the segregation or loss of any of the ingredients andmaintain the required workability. No water shall be mixed with the concrete after it has left the mixer.Where concrete is transported over long distances, the Contractor shall provide suitable means bywhich different grades of concrete are readily identifiable at the place of final deposit.3.21 Preparatory Works/Surface Preparation3.21.1 For Concrete Directly on Earth FoundationEarth foundation on which direct placement of concrete is specified, shall be rammed and consolidatedas directed by the Engineer such that it does not crumble and get mixed with concrete during or afterplacement. If the foundation is quite wet, the same shall be kept dry and then sufficiently consolidated,if necessary, a thin top layer of the wet soil shall be removed and replaced by sand or other suitablematerials as directed by the Engineer without extra cost to GAIL (INDIA) LTD., Care shall also betaken that earth from the sides also does not get mixed with the concrete, during or after placement,before it has sufficiently set and hardened.The earth foundation, over which concrete is to be placed directly, shall not be kept abandon at thespecified level and concrete shall be placed immediately following otherwise suitable measures shall betaken, as directed by the Engineer without extra cost to GAIL (INDIA) LTD.,
- Page 1 and 2: 0GAIL (India) Limited(A Nav Ratna C
- Page 3 and 4: 2S.NO.TECHNICAL SPECIFICATIONSINDEX
- Page 5 and 6: 41.1 GENERAL:A. GENERAL INFORMATION
- Page 7 and 8: 6SPECIFICATIONS1. SPECIFICATIONS FO
- Page 9 and 10: 81.8 DE-WATERINGWork for excavation
- Page 11 and 12: 102.9 TREATEMENT OF SOIL ALONG EXTE
- Page 13 and 14: 123.3 PLANT AND EQUIPMENTThe contra
- Page 15 and 16: 143.6.3 WATERWater used in the work
- Page 17 and 18: 16Unless otherwise specified in the
- Page 19: 183.13 DurabilityThe durability of
- Page 23 and 24: 22placement of concrete, the surfac
- Page 25 and 26: 24ii)iii)In framing the beam at dif
- Page 27 and 28: 262. Test for organic impurities.3.
- Page 29 and 30: 28The minimum interval between the
- Page 31 and 32: 303.30.3 Limitation to Use of Diffe
- Page 33 and 34: 32The joint filler shall be easily
- Page 35 and 36: 341 kg 1 No. 100 gms 1 No.3. Slump
- Page 37 and 38: 36It shall be ensured that the bars
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- Page 41 and 42: 40Oiling shall be done before reinf
- Page 43 and 44: 42For fair faced concrete, the posi
- Page 45 and 46: 446.3 RUBBLE MASONRY:-6.3.1. MATERI
- Page 47 and 48: 467.1.1.2 Hard Wood:Hard wood shall
- Page 49 and 50: 48The glass sheets for glazing shal
- Page 51 and 52: 50finish with minimum anodic film t
- Page 53 and 54: 52The tiles shall generally conform
- Page 55 and 56: 54Plaster as herein specified shall
- Page 57 and 58: 5612.9.5 FLOATING COAT OF NEAT CEME
- Page 59 and 60: 5813.1.a3 Preparation of Surface:Th
- Page 61 and 62: 6014.1.2 Preparation of surface:Pre
- Page 63 and 64: 62solution generously with brush. A
- Page 65 and 66: 64The Gypsum boards used for false
- Page 67 and 68: 661.4.1 Straining posts shall be pr
- Page 69 and 70: 687 Aluminum glazing section Hindal
193.17.2 Aggregates3.18 Water3.18.1 GeneralFor both design mix concrete and nominal mix concrete, the aggregates,(coarse and fine) shall bebatched by weight.In particular cases, or where weight-batching is not possible, proportioning by volume batching may beallowed by the aggregates throughout the period of construction. For this purpose, the Contractor shallsubmit to the Engineer sufficient data indicating the weight/volume relationship of the aggregates shallbe made by the Contractor to the satisfaction of the Engineer. Where aggregates are moist and volumebatching is adopted, allowance shall be bulking in accordance with IS (Part III).Suitable adjustments shall be made for the variation in the weight of aggregates due to variation in theirmoisture contents.Water may be measured either by weight or by volume. When measured by volume, it shall be by wellcalibrated conical shaped jar or vessel or from a calibrated tank filled to the mixer.3.18.2 Adjustment of Water Due to Moisture Contents in Coarse and Fine AggregatesIt is very important to maintain the water cement ratio constant at its correct value. For the correctdetermination of the amount of water to be added in the concrete mix, to maintain the water cementratio constant, the amount of moisture content in both coarse and fine aggregates shall be taken intoconsideration, be checked as frequently as possible, the frequency for a given job being determined bythe Engineer according to weather condition.3.18.3 Determination of Moisture Content in the AggregatesDetermination of moisture content in the aggregates shall be according to IS 2386 (Part-III). Wheretests are not conducted, the amount of surface water may be estimated from the following table:3.18.4 AdmixturesAggregatesSurface water carried by Aggregates% by weight l/m3Very wet sand 7.50 120Moderately wet sand 5.00 80Moist Sand 2.50 40Moist gravel stone chips * 1.25-2.5 20-40• coarser the aggregate, less the water it will carryAny solid admixture, to be added, shall be measured by weight, but liquid or semi-liquid admixturemay be measured by weight or volume.The Bidder shall indicate the brand name, the Manufacturer and the properties of any admixture to beused for the concrete as per Bill of Quantity items or on his own initiative.
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