Mivan formwork is the advanced formwork system made of strong and sturdy aluminum components that has great strength, durability, simple to install, adaptable and is used in the construction of residential units and mass housing projects.
In this article, we discuss the components, installation procedure, features, comparison, advantages, and disadvantages of Mivan shuttering.
Components of Mivan Formwork
The components of Mivan formwork are divided into 4 types based on the location of use –
1. Wall Components
A. Wall Panel
The basic and major component of Mivan formworks is the wall panels. It forms the face of the wall made out of an aluminum sheet properly cut to fit the exact size of the wall.
Rocker is an L-shaped panel having allotment holes for stub pin to support the wall panels.
It acts as a ledge to support the wall panels by forming a wall face at the top of the panel.
D. Stub Pin
It is the joining component of all other wall components.
2. Beam Components
A. Beam Side Panel
It is a rectangular structure cut into the required size of the beam which forms the sides of the beams.
B. Prop Head and Panel for Soffit Beam
In the beams, where there is no support from the bottom, prop heads are used to support the beam. It has a V-shaped head for easy dislodging of the formwork.
Soffit beam panel is a rectangular aluminum structure placed in the prop head to support the soffit beams.
3. Deck Components
A. Deck Panels
A horizontal flat surface upon which the slab is cast.
B. Deck Prop and Prop Length
Deck prop is the same as that of beam deck prop, here it is used to support the slab and bears the load coming on the deck panel.
Prop lengths are the vertical support to the deck prop which are adjustable as per the slab height.
C. Soffit Length
Soffit length provides support to the edge of the deck panels at their perimeter of the room.
4. Other Components
The other components used excluding wall, beam and deck components are internal and external soffit corners, exterior and interior corners for wall panels.
Mivan Formwork Erection Process
1. Placement of Aluminum Formwork
- Mivan formwork is majorly used in the places where the whole structures made of concrete.
- All formwork is cleaned and coated with an approved realize agents.
- The wall reinforcing steel is placed with the floor slab.
- Along with the wall reinforcing steel, prefabricated room-sized walls panels and floor slabs panels are erected.
- Plumb, level, and dimensions are checked.
- The aluminum alloy slabs are accurately made as per the required sizes.
- Spaces for windows, ducts, doors and other features such as staircases, façade panels, and chajjas are also integrated into these structures.
- The forms are then joined together using the pin and wedge system, which can be dismantled quickly after the concrete structure is made.
2. Pouring of Concrete
- After casting the forms, high-quality concrete is poured.
- This concrete takes the form and shape of the cast.
- At least two operatives should be on standby during concreting for checking pins, wedges and wall ties as the pour is in progress.
- Special attention to be given while pouring concrete for dislodging of pins/wedges, slipping of props or overspill of concrete at openings.
3. Striking of Formwork
- Normally all formwork can be struck after 12 hours of concreting.
- First, the wall formwork is strike down, followed by deck formwork.
- The removed formwork is cleaned with scrapers and wire brushes as soon as they are struck.
- Once cleaned, it is transported and stacked properly for the next use.
Features of Mivan Formwork
The major features of Mivan formwork are given below –
1. Load Carrying Capacity
The load-carrying capacity of Mivan formwork is 7-8 Tonnes per square meter. Mivan formwork is lightweight and weighs around 18-20 kg per meter square.
2. Striking Time
The striking time of vertical (wall) formwork is 12 hours after concreting or when concrete strength has reached 2N/mm2 and horizontal (deck) formwork is 36 hours after concreting or when concrete strength has reached 10N/mm2.
As the panels of Mivan formwork are made of structural grade aluminum alloy, they are very durable and sturdy. A single component can be repeated around 200 times.
4. Cycle Time
High speed of construction can be achieved by this system that means faster completion of the project. Approximately, the times required to cast floor is 7 days with the use of Mivan formwork.
Comparison between Mivan Formwork and Conventional Formwork
|Factors||Conventional Formwork||Mivan Formwork|
|Speed of Construction||The pace of the construction is slow due to step – by – step completion of different stages of activities is required. Erection of formwork, concreting and de-shuttering is a 2 week cycle.||in this system, the walls and floor are casted together in one continuous operation in matter of few hours and in built accelerated curing overnight enable removable and reuse of forms on daily cycle basis|
|Aesthetics||In the case of RCC structural formwork of column and beams partition brick wall, the columns and beams show unsightly projections in room interiors||The room- sized wall panels and ceiling elements cast against steel plates having smooth finishes and interiors have neat and clean lines without unsightly projections in room interiors.|
|External Finishes||Cement plastered brickwork, painted with cement based paint.||Textured/ pattered colored concrete fascia can be provided which does not need frequent repainting.|
|Useful Carpet area as % of Plinth area||Efficiency around 83.5%||Efficiency around 87.5%|
|Consumption of raw materials|
|Normal||Consumption is more than that used in conventional structure.|
|Maintenance||High due to repairs in plaster of wall and ceiling, Repainting and leakages due to plumbing installations.||The walls and ceiling being smooth and high quality concrete repairs for plastering and leakage are at all required frequently|
Advantages of Mivan Formwork
- High-quality formwork ensures consistency of dimensions.
- On removal of the mold, a high-quality concrete finish is produced to accurate tolerances and verticality.
- The total system forms the complete concrete structures.
- Custom designed to suit project requirements.
- Unsurpassed construction speed.
- Panels can be reused up to 250 time
- It can be erected using unskilled labor.
Disadvantages of Mivan Formwork
- The concealed services become difficult due to the small thickness of components.
- It requires uniform planning as well as uniform elevations to be cost-effective.
- Modifications are not possible as all members are caste in RCC.
- The large volume of work is necessary to be cost-effective i.e. at least 200 repetitions of the forms should be possible at work.
- The formwork requires a number of the spacer, wall ties, etc. which are placed @ 2 feet c/c; these create problems such as seepage, leakages during monsoon.
- Due to box-type construction shrinkage cracks are likely to appear.
- The heat of hydration is high due to shear walls.