Tunnel Formwork consists of a shell and a carriage, which is made of segments with a width of 1.5 meters, which allows the carriage to move on the rail in the longitudinal direction of the tunnel and provides the possibility of concreting in the next stages. According to its application, the tunnel formwork is produced in different shapes like horseshoe, oval, etc. Tunnels and defense installations are structures that are built underground, and each of these structures has different characteristics in terms of the construction of the tunnel template. Various tools such as rock bolts and shotcrete are used to maintain tunnel formworks in the first stage of excavation. This type of formwork, while having speed and convenience in execution, the amount of reinforcement used is about 30% less compared to concrete structures, which will save money.
The dimensions of the common length in the lining tunnel formwork are 6 and 9 meters, and this formwork is divided into two categories, hydraulic tunnel formwork and mechanical tunnel formwork, according to the dimensions and in terms of the opening and closing mechanism. In tunnel formworks of the first type, it is possible to open and close the formwork segments using hydraulic jacks, and in the mechanical formwork, it is possible to open and close the segments using manual or oil jacks. Usually, hydraulic formwork system is used in large sections due to the heavy segments, and mechanical formwork is used in small sections due to economic efficiency and limited space. In the following, Omran Sanat introduces you to tunnel form formatting.
All the hydraulic and even mechanical lining tunnel formworks have a carriage that the crown and tunnel wall segments, each of which is basically one and a half meters in size, are installed on this carriage and with the embedded wheels that are under the foundations of this The carriage is about to move. This movement of the carriage in the form of hydraulic lining is done by the driving system or the traction force. It should be noted that all the two screws holding the electrical panel and the jacks are installed on this carriage as well, and the opening and closing of the crown and wall segments of the formwork are done using the same hydraulic jacks, which are usually diagonal, horizontal and vertical. are done.
As mentioned in the hydraulic formwork part, the mechanical lining formwork also has a carriage, where the crown and tunnel wall segments are opened and closed by two mechanical screws. In order to restrain the force, in addition to these two screws, which play the role of transmitting the force to the segments, the formwork segments are closed on the concrete floor of the tunnel by special shoes that are installed on the anchor bolts, and this kind of force is restrained. . The mechanical tunnel formwork has a body vibrator system, which are mainly electric or pneumatic, and the electrical system is complex. Also, valves for concreting and inspection are installed on the wall segments and holes are installed on the crown segments to connect the pump pipes.
The tunnel form system allows you to concretize walls and ceilings in one day. The construction time is reduced by the tunnel formwork system quickly and significantly compared to other methods. The purpose of producing the form tunnel molding system of Omran Sanat Paya Company is to provide you with more speed, quality and accuracy in construction. The construction of this formwork has led to a great saving in carpentry, installation and electrical work, so that this formwork can be used up to 500 times before repairs, and the use of modern technology in the production of tunnel formworks strengthens the form of these formworks. It makes it more durable.
The tunnel formwork system is divided into two parts: semi-tunnel and full tunnel:
In this system, which is called semi-tunnel, large formworks with bases installed on rollers or wheels, which are in the form of a table, cover the entire ceiling of the space, and the roof reinforcement is done on them, and then the concrete operation is done. It is done. This method is similar to the conventional tunnel system, which makes it possible to concretize the roof and the wall at the same time. It is necessary to know that in this system, after the implementation of the structural walls and roof, the walls of the main facade can be implemented with various materials.
In this tunnel system, concrete strip slabs or simple pre-slabs that are placed on the edge of the side walls of the spaces are installed before the concreting operation of the upper reinforcements of the pre-slab to use the pre-slab and the connection of the wall and ceiling rebars is also done. Then the concreting of the upper part of the joints between the prefabricated slab and the pre-slab with the roof is done. In this implementation system, the outer walls are molded and concreted at the same time as the other walls, and this process causes the removal of parts from the building to be very complicated. The reason for the small size of the parts is to allow the parts to be removed from the windows and doors.