Tunnel mold (Tunnel form)
Various motivations including improvement of concrete face quality, high speed and industrialization of housing have been effective in transferring from traditional formwork system to industrial one. It is not a long term (about 40 years) that passes from import of modern technology of mass housing by tunnel mold method. It is some years that officials consider to necessity of constructing house in suitable numbers in the state and Parsian Ghaleb commercial, Industrial and production group designed and produced tunnel mold system by available software and Hardware facilities.
Considering to importance of cost price of construction, quality of operation and speed in completion of projects, tunnel form mold is suitable for mass constructors as it has all mentioned advantages due to solid ceiling and wall in one step. Now, tunnel form mold system has a good position as a modern and efficient technology in our state.
Operation of ferroconcrete constructions by tunnel form methods is one of used method in concrete ceiling and wall loading system. This system is called as tunnel because operation of ceiling and wall formwork is performed in cell and simultaneously. In this method, tunnel mold (a metal mold in tunnel form) is used for a solid formwork concrete ceiling and wall so that concrete frame of building includes concrete shear walls and concrete slab ceilings and has not any usual structural element such as beam and pillar in which it is possible to do formwork and transfer to higher floor after passing 2 days.
Tunnel molds have approximate size of spaces (for example size of room). There is no need to change molds to smaller sizes in formwork and they may exit from space with same size. Tunnel molds may be sent out after wall and ceiling concreting and primary concretion by spacing molds from concrete walls and moving on a wheel or roller horizontally. Various elements of these molds are: panels (wall, back and ceiling panels), fillers (wall and ceiling panel fillers), levelers (fixed and moving), jacks, wheels and connectors, platform and rafter and romka رامکا, roller and stopper, and other connectors and restrainers which all are produced after designing in technical section.
Considering to importance and priority of housing subject and construction industry in development program of the state, it is necessary to use modern technology (tunnel mold) in the field of promoting quality and quantity of housing while observing technical standards and national regulations of construction and using the best methods of housing construction. The optimized floors are 8 to 10 floors in this method. Expenses of using tunnel mold for frame and internal walls and coating is 19% and 38% respectively less than concrete and metal frames. This system is merely suitable for mass plans.
It has a set of executive (structure and vibration), economic, and environmental advantages. Other advantages of tunnel mold method are high speed in operation, expense economies, easy operation, supervision of structure and more resistance against earthquake. In this system, concreting of each floor is performed at each step of formwork which has more speed and efficiency than beam and pillar traditional method in ordinary concrete constructions. Along with the mentioned concreting, electricity piping and installations casing are performed which decrease time of operation.
Advantages of Tunnel Form System
- decrease of project construction term
- decrease of expenses due to short term of construction
- economy in using man power and workers in terms of work speed
- not using capital for a long time for tunnel form project
- Various uses of tunnel form mold in different projects and consequently, tunnel molds are considered as a permanent capital for the executers.
- possibility of performing one floor of a big building in a short term
- increase of structure quality using tunnel mold system
- omission of joinery and internal architecture in terms of flat and glossy surfaces
- to make accurate and ordered internal dimensions due to high accuracy of molds
- use of tunnel form mold system causes economy in use of many common materials such as wood, nail, wire and ironware
- tunnel mold system cause good use of available area
- The structure constructed by tunnel molds are very resistance against fire and earthquake due to solid concreting of wall and ceiling
- operation of concrete structure by use of tunnel form mold makes project construction similar to an industrial production line and consequently, has high speed and efficiency due to daily repeat
- Tunnel form mold may be used by semi-specialized powers due to its simplicity.
- In this method, ready mesh may be used which decrease operation term and expenses.
Some used pieces in tunnel form mold:
Locker (cast-iron locker)
Ramka one-sided seat
Ramka two-sided seat
Ramka one-sided supporter
Ramka two-sided supporter
Claw (external brocket seat)