NEW DELHI-110 003
1.NAME OF PAPER :
MODERN TECHNIQUE OF CONSTRUCTION
2.DESCRIPTION OF WORK:
Use of Tunnel form for the construction of earth quake housing project in Republic of Turkey in 2001
3.METHODOLOGY ADOPTED IN EXECUTION
Form work is one of the most important factors in determining the finished appearance of in situ construction, strength & durability of the structure. Yet the role of the form work and the choice of the correct form work system have been subjects neglected in the construction industry. Today the trend in the construction industry is towards reduced construction time and cost, improved work place safety and standardization. In the recent past, the incidents of natural calamities like earth quake etc have become were frequent. The quick re-habilitations of the victims is a long challenge being faced by most of the countries.
To catch the above trends, it is imperative to develop form work systems which are productive, quick and easy to erect, quick and easy to strike, reusable at least more than 100 times and cost effective, tunnel form system is one of the such systems. This is a method in which the walls and the slab in a single operation with collapsible ensuring easy workability. In this system the construction time is much shorter than the conventional methods. Several studies shows that almost 50% of the time is saved compared to additional methods for completion of the project thereby reducing overall cost and risk of prolongation of duration. ii.USE OF TUNNEL FORM
-Fast construction fits to tight construction schedule.
-One set of tunnel form can provide a for half day cycle in place of 20-25 days cycle with conventional methods. -Saving through reduced construction time. No effect of price hike
-Shuttering may be stripped after 12 hours of the concreting
-A monolithic structure, which needs the requirements of building codes of the countries/ area located in earth quack zones.
-Form work strength of 5.5 t/ Sqm. At normal pouring rates.
-A nice concrete surface that eliminates much of the finishing work like plastering
-A prefect daily rhythm for the other operation at site
-Dimensional accuracy that allows pre-fabrication of finishing material.
-Complete work place safety
SALIENT FEATURE OF PROJECTS
Number of dwelling units = 3576 Nos.
Built up area = 419700 Sqm
Project cost = $ 67 M.
( Rs. 294.80 crores)
DATA FOR TUNNEL FORM SET
Number of sets=21 Nos
Area of each set=160 Sqm
Days consumed for 1,251.600 Sqm
Shuttering = 180 days
Average cycle time = 1.7 days
1.TYPE & DESIGN OF THE STRUCTURE
The structure is designed as a portal frame having monolithic casting of the wall, slab and columns. The beams are eliminated and a columns are in built with the wall.
The foundations are completed with the conventional method and dowels are left out for column and wall reinforcement. The wall reinforcement is tied in position alongwith the electrical conduits and reservations for the plumbing fixtures before placing the tunnel forms in position.
3.TUNNEL FORM WORK FOR WALL AND SLAB
The tunnel form is placed in position with the help of a tower crane to half shells which are placed together to form a room or a cell, while several shells are making an apartment. After placing two tunnel forms together, the level can be adjusted with the help of its leg jacks and wheel strut. The soffit level can be adjusted with the inclined prop. The...