What is a diaphragm wall?
Diaphragm walls are underground structural elements commonly used as retention systems and permanent foundation walls. They can also be used as groundwater barriers. … Diaphragm walls tend to be used for retaining very deep excavations as they can be designed to take very high structural loads.
Why do we use diaphragm wall?
The use of diaphragm wall structure is one of the most commonly used methods to solve the construction of a deep foundation pit in large tunnel working shafts. It can be used as the retaining structure for working shafts as well as one part of the permanent structure of the working well.
What is a diaphragm retaining wall?
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 construction sequence of diaphragm wall?
Typical construction sequence of a diaphragm wall panel – (A) panel excavation, (B) recycling / replacement of drilling fluid and placement of stop-end with water-bar, (C) reinforcement cage installation and (D) concrete placement using the tremie method Waterproofing performance.
Why is bentonite used in diaphragm walls?
A diaphragm wall (slurry wall) is a reinforced cast-in-place continuous concrete wall. The construction includes the excavation of a trench under the protection of a support suspension (i.e. a thixotropic slurry such as bentonite mud for example) designed to temporarily stabilize the trench wall.
What are the benefits of diaphragm slurry wall?
The DWall is capable of resisting bending moments and shear forces resulting from lateral soil loads which make them a suitable choice for deep excavations. 4. The DWall is water tight; no dewatering is required and hence has little effects on adjacent structures. 5.
What is bentonite used for?
Bentonite is the active protective layer of geosynthetic clay liners. Drilling: Another conventional use of bentonite is as a mud constituent for oil and water well drilling. Its roles are mainly to seal the borehole walls, to remove drill cuttings and to lubricate the cutting head.