The minimum period for removing formwork

In normal circumstances, the ambient temperature does not fall below 15 C, ordinary Portland cement is used, and adequate curing is done, following period is acceptable.

Part of Structure

The minimum period for removing formwork

Sides of foundations, columns, beams and walls

24 hours

 

Under sides of slabs of up to 4.5 metre span

7 days

 

Under sides of slabs of above 4.5 metres span and under sides of beams and arches up to 6 metres span

14 days

 

Under sides of beams and arches over 6 metres  span and up to 9 metres span

21 days

Cantilever slabs and beams 

21 days

Domes, shells and other structures of special nature

As per written instructions of officer-in-charge.

The officer-in-charge may however extend the periods noted where necessary by giving written instructions to the contractor.

Comments

Post a Comment

Popular posts from this blog

Portal beam structures

Image
Portal beam Portal beam structures eliminate the necessity for interior columns, allowing the entire floor area to be utilized without obstructions. This provides greater flexibility in layout and design. Additionally, they facilitate the movement of people, machinery, and goods, which is especially important in factories, warehouses, and retail spaces. This makes the building future-proof, as it can accommodate various uses over time without significant structural changes. Load transfer Vertical loads                                                                                                                                            ...
Read more

Why we use conceal beam in slab design

  Conceal beam A reinforced concrete beam is provided within the slab, whose depth is equal to the depth of the slab. Advantageous of a concealed beam Load Distribution Concealed beams are crucial for distributing loads more evenly across the slab. This distribution reduces stress concentrations at any single point, making the structure more efficient and helping to control cracking. By spreading the loads, the beams ensure that the slab can handle heavier weights, such as those from an overhead water tank, without compromising structural integrity. Aesthetic Appeal Since concealed beams are embedded within the slab, they do not protrude from the ceiling or floor. This results in a cleaner, more aesthetically pleasing finish to the interior space. In residential or commercial buildings, this can be a significant advantage, as it provides a seamless look without visible beams. Increased Headroom By embedding the beams within the slab, the overall height of the room is not reduced. T...
Read more

Number of blocks in one metre square area (for 300 mm x 150 mm block)

Image
Usually, we represent the number of blocks in terms of area (m2) rather than length.                                    Consider a block of dimension 300 mm x 150 mm x 100 mm . ( wall thickness is 100 mm )   but for the accurate value we should consider a 10 mm thick mortar layer around the blocks for binding them to each other. Therefore, we consider a single block's length (including mortar) is 310 mm and its height is 160 mm. The area of one block including mortar is 0.31 m × 0.16 m = 0.0496 m2. The number of blocks in one metre square (m2) can be calculated as 1/0.0496 = 20.16 blocks Any area's block count can be determined by multiplying it by 20.16  
Read more