How is a diaphragm wall constructed?
Diaphragm wall is a reinforced concrete structure constructed in-situ panel by panel. The wall is usually designed to reach very great depth, sometimes up to 50m, mechanical excavating method is thus employed. Typical sequence of work includes: Inert reinforcement and placing of concrete to form the wall panel.
Is code for diaphragm wall construction?
Basic Details
| IS Number : | IS 9556 : 1980 |
|---|---|
| Document Title [Eng-Hn] : | Code of practice for design and construction of diaphragm walls |
| No of Revision : | |
| No of Amendments : | 1 |
| Technical Department : | Civil Engineering Department |
What is the minimum concrete cover for diaphragm walls?
Unless otherwise approved by the Engineer, a minimum cement content of 400 kg/m3 is to be employed in making concrete which is to be placed by tremie methods under a bentonite slurry, in accordance with B.S. 8004.
Which of the following is the chemical used for construction of diaphragm wall?
Bentonite slurry is placed in trench added to maintain atleast 3 feet above ground water table and within 2 feet of top of guide wall.
What is a diaphragm construction?
Diaphragms are a roof, floor or other system transferring lateral forces applied to a building to the vertical elements, such as the shear walls. The sheathing transfers both vertical gravity load to the regularly spaced framing members and shear loads horizontally in diaphragm action.
Is a diaphragm wall a foundation?
Diaphragm walls are underground structural elements commonly used as retention systems and permanent foundation walls. They can also be used as groundwater barriers.
What are diaphragms for structures?
What is bentonite slurry?
Bentonite slurry is a combination of sodium bentonite and slurry. A slurry is a thin sloppy mud or cement or, in extended use, any fluid mixture of a pulverized solid with water, often used as a convenient way of handling solids in bulk.
Why are diaphragm walls so expensive?
The high cost of diaphragm walls can make them uneconomic unless they can be incorporated into part of a building structure. As such, they are suited for deep basements, underground car parks and rail stations, tunnel approaches, underpasses, deep shafts for tunnel ventilation, pumping stations, and so on.
Are diaphragm walls retaining walls?
A Diaphragm Wall is a deep reinforced concrete continuous retaining or cut off structure often used as permanent works on a project. They are particularly suitable for large open sites where structures greater than 25m deep are required and they can be constructed in most ground conditions.
What is the purpose of diaphragm wall?
How is the diaphragm wall panel construction done?
The diaphragm wall panel construction entails three steps: the construction of guide wall, the panel exca – vation (demolition – removal – stabilization), and the construction phase (reinforcing cage – casting – cu – ring).
Which is the most delicate issue in diaphragm wall construction?
One of the most delicate issues in the diaphragm wall construction is represented by the waterproof joints between panels.
How are diaphragm walls used to remove soil?
Diaphragm wallsare rectangular-section exca- vations with a complete ground asportation that is made in situ. The result is an underground concrete wall. They are essentially retention walls, which are con- structed for instance at wharfs. A rectangular-section tool is generally used to remove the soil, thus cre- ating a rectangular excavation.
What kind of machine is needed for diaphragm wall?
Although it has been more than 20 years ago, two drilling machine categories still remain to achieve a diaphragm wall: • on one hand, the rop/cable operated grab (mechanical clamshell) and the hydraulic grab (Kelly bar mounted), • and on the other hand, hydraulic cutter machine, also called hydromill or hydrofraise.