Diaphragm Walls

Another form of retaining wall is the diaphragm wall system.

Trench thickness from 600mm to 1500mm by 2800mm long.
Trench depth up to 75 metres using 150 tonne to 170 tonne rig working capacity

Applications

The most popular use of a diaphragm wall is for the construction of multilevel basements and for top –down building construction method. The trenching process of this diaphragm wall system is aided by bentonite fluid support. During the excavation process bentonite is introduced and recycled during the construction process. Bentonite is used during the excavation process to facilitate the removal of the cuttings when using the trench cutter, until reaching desired depth. This is later replaced by placing concrete in the trench via the tremie method. Bentonite is returned to holding tanks on site to undergo treatment and reuse.

The diaphragm wall system is a fantastic solution compared to any other conventional retaining wall systems because of increased water tightness by minimizing vertical joints. The use of the diaphragm wall system is to alleviate issues in constructing underground tunnels along heavy public presence, deep basements without endangering the stability of the foundations of the nearby buildings. Diaphragm wall system can be applied to water storage, sewage disposal shafts, security vaults, pits, and wharves, containment of contaminated area and control of toxic effluents travelling underground.

Diaphragm wall ancillary structure comprises of de-sanding equipment, silos, holding tanks, transfer pumps, mixer tanks and compressors.

Advantages

Ideal for top down construction projects.
Can be installed in virtually all soil conditions including high strength rock.
Reduced noise and vibration compared with other shoring techniques such as sheet piling.
Very accurate method of construction with high tolerance levels.
Removes the requirement for dewatering the site.
Can be used in the immediate vicinity of existing buildings.
Can be designed to carry structural loads thereby reducing the foundation costs.

5-7 Charles Street Parramatta DWall

LB 8100-02 excavating at Parramatta

Project Outline

NSW

Products / Services

Diaphragm Walls Sheet Piling

The project is a mixed used residential and commercial building with 5 basements to be developed by GFM Investments.

Scope of Works

Avopiling Australia Pty Ltd was contracted to undertake the design and construction of the temporary works to maintain the integrity of the wall structure with the installation of 96No PU18 sheetpiles.x 8.00 metres long and the design and construction of the perimeter basement retention wall made of 640 mm wide diaphragm wall panels x 21.00 metres deep.

M6 Stage 1 C2 Shaft and Cut and Cover

MC64's cutting and grabbing
Bentonite Plant
Nightwork
LB 45 at Cut and Cover

Project Outline

NSW

Products / Services

Continuous Flight Auger Piles Diaphragm Walls Segmental Casing

Construction of M6 Stage1 Project is by CPB Ghella UGL JV. The M6 Stage 1 connects President Avenue at Kogarah to the M8 at Arncliffe.

Scope of Works

Avopiling Australia Pty Ltd scope is to construct the C2 Shaft and the Cut and Cover section. The C2 shaft consist of 8 diaphragm wall panels 1000 mm wide to depth of 38.00 meters. The cut and cover section is made up of a 80No diaphragm wall 1000 mm wide to depths of 30.00 metres and a secant pile wall with a combination of 106No CFA and 102No bored piles using segmental casing to depths approximately 24.00 meters and 27No barrettes 1000mm wide x 35.00 meters deep.