Description

Semi-tunnel system (operation of wall by ascending metal formwork and ceiling by sky deck)

Sky deck is used for operation of ceilings. These decks are set among walls after performing wall of the floor and concreting is performed after steel and box working. Pay attention that this system has been designed for concrete works with mass volume and needs many equipment including heavy lifts with long arm and high capacity. In case of existing equipment, this system has very efficient speed. Speed and simplicity of formwork is an important factor in improvement of speed in performing reinforced concrete structures. Formwork system provides simultaneous and parallel formwork in addition to accelerating it by sky deck. In this in place concrete system, walls formwork are performed as usual using wall molds but sky decks are used for ceiling formwork and slab of reinforced concrete of ceiling is performed. The structure gained by this method is reinforced concrete loader wall and a known system based on national and international standards and bylaws. In addition, this system has suitable vibrational operation and may be performed in areas with many earthquakes. As regards, this executive method produces a system similar to tunnel system in two orthogonal direction of building, it is necessary to supply shear walls in two directions for better operation of lateral loading. A special architecture is provided by such distribution of reinforced concrete walls in plan of structure. Reinforced concrete ceilings in this system may be designed and performed in flat slab or block. In this system, it is possible to prepare and predict distribution routes of mechanical and electrical installations at armature and before concreting structure.

Cifa–Taraband mold (mechanical ascending system)

Mechanical ascending system

Introduction

Dam construction industry has been commenced by modern method especially great dams from 5 decades before. As bases of winning power of water pressure in concrete dams is transfer of this power to valley walls and in fact geometric form of dam, these dams are constructed from reinforced concrete. Cifa–Taraband mold is used for concreting operation of concrete dams. Operation of the mentioned system is based on one-sided or two-sided concreting and transfer of new concrete power by main structure of mold to concrete of previous step. The power gained from new concrete brings in surface of mold and then, transferred to two supporting bolts behind mold and to platform and finally to shear belt by vertical soljers.

Structure

Width of mold based on maximum vicinity to dimensions of line. There are some molds in 15.3 * 4 meters dimensions. Plumbing jacks, platform and regulation bolt are used for restraining this great mold. Teraband mold is a set of mentioned pieces plus concreting platform and other lateral pieces including:

• a complete set of soljer taraband mold (vertical clamp)
• perforated cornerstone
• connector of soljer and small concreting platform
• concrete platform
• mold of platform body
• grating
• cross brace
• other connectors and small concreting
• big concreting platform
• shield
• double screw
• connectors

Application

Concreting operation of weight concrete dams and arcuate concrete dams, retaining wall and any concrete structure with high height and high iteration ratio in formwork operation may be considered as usage cases of this system. Meantime, this system is used at places in which use of belt is not possible. it is more easy assembled than traditional formwork method and able to be transferred upright.

Advantages

Applied advantages of this system are rapid installation, ability to work on various surfaces and slopes and simplicity of preparing concrete. It is more economic that dimensions of mold structure are used in module form in most projects. Other advantages of the system are its high reliability and security of executive powers and loading ability and using in various surfaces. It is also applied in high walls or structures with wide formwork area in which thickness of wall is less. In this system, each mold has ability of shea شی belt placement of next concreting step and this case facilitates high structures operation with different geometric structures.