Detail specification of lime concrete in foundation are as below:-
Detail specification
Materials- All materials shall be per standard specification. Coarse aggregate shall be hard, well-burnt or over burnt brick ballast of 40mm gauge. It shall be deep cherry red or copper colour and shall be clean, free from dust, dirt and other foreign matters. It shall be homogeneous in texture and roughly cubical in shape. Ballast which appears porous or shows signs of saltpetre shall not be used. Brick ballast shall pass through square mass of 52.5m and not more than 20 per cent pass through a mesh of 25mm. any rejected material shall be removed from site of work within 24 hours.
Fine aggregate shall be of surkhi or sand or cinder as specified and clean and free from dust, dirt, and foreign matters. Surkhi shall be made of well burnt brick or brick bats (not over burnt) and shall pass through a sieve of 2.5 meshes per sq cm (144 meshes per sq in). Srkhi as preferable better concrete.
Lime shall be white fat lime (unless otherwise specified) and shall be freshly burnt and free from ashes and other foreign matters. Lime shall be slacked at site of work and screened through a sieve of three meshes to a cm (8 meshes to an inch).
Proportion- The concrete shall consist of 1 cu m of brick ballast, 0.32 cu m of surkhi (sand or cinder) and 0.16 cu m of white lime in the proportion of 100: 32: 16 by volume.
Mixing- Mixing shall be done on a clean waterlight, masonry platform of sufficient size. Brick ballast shall be staked in a rectangular layer of uniform thickness usually 30cm (12”) high and well soaked with clean water a period of at least three hours.
Lime and surkhi shall be measured with wooden box in the proportion of 1:2 and mixed thoroughly dry to have uniform colour. The dry mix of lime and surkhi shall be spread over the staked ballast required thickness to give the specified proportion. Then material is mixed at least three times. Clean water is then added slowly for mixing purpose. Concrete shall be mixed only for day’s work, old and slate concrete shall not be used. For big work the mixing shall be done by machine. The water shall be added slowly to the required quantity and the mixing shall be continued for at least one minute, till a mix of uniform colour and workable consistency is obtain and should be such that the ballast do not separate from the mortar.
Laying and compacting- Bed of foundation trench shall be lightly sprinkled with water before concrete is laid. Concrete shall be laid slowly and gently (not thrown) in layer of not more than 20cm (8”) and thoroughly consolidated to 15cm (6”) with 6kg (12lbs) iron rammer. During consolidation concrete should be kept free from earth, dirt, leaves and other foreign material. The consolidation shall be checked by water test, by digging hole about 7.5cm dia. and 7.5cm deep in the concrete and filling water. The water level should not sink more than 1.25cm in 15min if concrete has been well –consolidated.
Joint and consecutive layers- When joint in a layer of concrete are unavoidable, the end shall be sloped at an angle of 30 and junction of different layer shall break joint. In laying upper layer of concrete, the lower surface shall be made rough and cleaned and watered before upper layer is laid.
Curing- Concrete after compaction shall be wet for a period of at least 7 days and no masonary shall be constructed upon it during this period. The curing shall be done by spreding gunny bags or sand or kipping them wet by water-can at regular interval.
Measurement- Measurement shall be taken in cu m(cu ft) for the finished concrete. The length and breadth shall be measured correct to 1 cm and depth correct to 0.5 cm. the rate shall be for the complete for the complete work including the cost of form work if required, and all tools and plants.
Lime concrete in foundation- Detailed specification
there is a mistake u have written for the complete twice!
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