Technical Specification for Pain Cement Concrete (P.C.C) 1:4:8 & (P.C.C) 1:3:6
Providing and laying cement concrete 1:4:8 (1 cement : 4 coarse sand : 8 hand broken stone aggregate 40 mm nominal size) and curing complete excluding cost of form work in foundation and plinth.
1.0. Materials
1.1. Water shall conform to M-1. Cement shall conform to M-3. Sand shall conform to M-6. Hand broken stone aggregate 40 mm. nominal size shall conform to M-12.
2.0. Workmanship
2.1. General
2.1.1. Before stating concrete the bed of foundation trenches shall be cleared of all loose materials, leveled, watered and rammed as directed
2.2. Proportion of Mix:
2.2.1. The proportion of cement, sand and stone aggregate shall be one part of cement. 4 parts of coarse sand and 8 parts of hand broken stone aggregates and shall be measured by volume.
2.3. Mixing:
2.3.1. The concrete shall be mixed in a mechanical mixer at the site of work. Hand mixing may however be allowed for smaller quantity of work if approved by the Engineer-in-charge. When hand mixing is permitted by the Engineer-in-charge in case of break-down of machinery and in the interest of the work, it shall be carried out on a water tight platform and care shall be taken to ensure that mixing is continued until the mass is uniform in color and consistency, However in such case 10% more cement than otherwise period 1 1/2 to 2 minutes. The quantity of water shall be just sufficient to produce a dense concrete of required work-ability for the purpose.
2.4. Transporting & Placing the Concrete:
2.4.1. The concrete shall be handed from the place, of mixing to the final position in not more than 15 minutes by the method as directed and shall be placed into its final-position, compacted and finished within 30 minutes of mixing with water i.e. before the setting commences.
2.4.2. The concrete shall be laid in layers of 15 cm. to 20 cm.
2.5.1. The concrete shall be rammed with heavy iron rammers and rapidly to get the required compaction and to allow ail the interstices to be filled with mortar.
2.6. Curing:
2.6.1. After the final set, the concrete shall be kept continuously wet if required by pounding for a period of not less then 7 days form the date of placement.
3.0. Mode of measurement and payment
3.1. The concrete shall be measured for its length, breadth and depth, limiting dimensions to those specified on plans or as directed
3.2. The rate shall be for a unit of one cubic meter.
Ref Image by Jigar Darbar
Article Ref by Road & Building Dept. Technical Specification Booklet
Tags:
Civil Engineering