An Introduction to Monolithic Construction using Aluminum form work system
Dr. Rajiv Goel
AMIE, M.Tech(Structure), PhD (Delhi University)
Arocon Real Estate Pvt. Ltd.
Arocon Golf Ville, GH-7, Crossings Republik,
NH-24, Ghaziabad – 201016
Ph: 9582282266, 9582282277, 9582289096, 9582289097
The Aluminium Formwork System was developed by W. J. Malone, a Canadian Engineer in the late 1970s as a system for constructing low–cost housing unit in developing countries. The units were to be of cast-in-place concrete, with load bearing walls using a formwork of aluminium panels. To be erected by the hundreds, of a repetitive design, the system ensured a fast and economical method of construction.
The in-situ construction of all walls and partitions reduces the requirement for follow-on wet trades. The concrete surface finish produced with the aluminium forms allows achievement of a high quality wall finish without the need for extensive plastering.
- This is one of the systems identified to be very much suitable for Indian conditions for mass construction, where quality and speed can be achieved at high level.
- The speed of construction by this system will surpass speed of most of the other construction methods/technologies.
- The labour handles this method effectively to speed up the construction, to assure quality control and durability. Adoption of this system reduces overall cost of the structure.
- Aluminium Formwork System is highly suited to load bearing wall construction whereas traditional formwork consisting of plywood and timber is not suitable to the high pressures of fresh concrete on the wall.
- COST: Use of this formwork in load bearing design gives an average of 15 per cent cost saving in the structure of the building and increased usable floor space of 8 per cent over RCC design.
- TIME: For 100 per cent work, construction through slab beam wall construction takes X time and through Aluminium Formwork technology the time required is 1/6th of the X time.
- ENVIRONMENT FRIENDLY: The technology is environment friendly as there is no use of timber. The formwork gives the box or cellular design resulting in the walls giving support to the super structure in two directions. As a result, the structures are more resistant to earthquakes than the traditional RCC column and beam designs.
- LIFTING: As the Aluminium Formwork is lightweight, no tower cranes are required for the same unlike in tunnel framework.
- LABOURS: Due to simplicity of the assembly, only unskilled labours are required with minimal supervision.
- REPETITIONS: The Aluminium Formwork System is removable and can be reused hundreds of times with little maintenance.
- SCRAP VALUE: Moreover, the requirement of steel is also reduced in this technology as aluminium has a higher scrap value.
- The simplicity of Aluminium Formwork and the repetitive nature of the assembly process make it possible to accurately programme construction sequences and thus cycle times well in advance.
- In addition, this enables the unskilled labour to work with the formwork, therefore reducing the burden on skilled labour when this is in short supply.
- On leaving the factory, all panels are clearly labelled to ensure that they are easily identifiable on site and can be smoothly fitted together using the formwork modulation drawings.
SIMPLE ASSEMBLY SYSTEMS
PIN AND WEDGE SYSTEM
- The panels are held in position by a simple pin and wedge system that passes through holes in the outside rib of each panel.
QUICK STRIP PROP HEAD
- One of the principal technical features which enables this speed to be attained using a single set of formwork panels is the unique V shaped prop head which allows the ‘quick strip’ to take place whilst leaving the propping undisturbed. The deck panels can therefore be reused immediately.
- The in-situ construction of all walls and partitions reduces the requirement for follow-on wet trades.
- The concrete surface finish produced with the aluminium forms allows achievement of a high quality wall finish without the need for extensive plastering.
- Doors and windows are formed in position, with this high degree of precision items such as door and window frames can be directly installed on site with minimal re-sizing required.
- High quality Aluminium Formwork panels ensure consistency of dimensions.
- On the removal of the Formwork mould, a high quality concrete finish is produced to accurate tolerances and verticality.
- The high tolerance of the finish means that no further plastering is required.
- Typically a 3mm to 4mm skim coat is applied internally prior to finishing and a 6 mm build up coat prior to laying tiles.
Necessity of the Aluminium Form work System
- Rapid urbanization has resulted in a geometric increase in the housing demand, which cannot be fulfilled using conventional materials and methods of construction.
- The traditional or conventional method of construction for mass housing & high rise buildings is comparatively, a slow process and has limited quality control, particularly when a large size project is involved.
- It is therefore obligatory to work out a method or a scheme where the speed and quality of construction are controlled automatically by a systematic approach.
- Therefore Aluminium Formwork System (AFS) identified to be suitable for Indian conditions for mass housing construction where quality and speed can be maintained at a reasonably high level