Diaphragm Walls, DPT

This project for the Dublin Corporation required the construction of three access shafts and 1380m of tunnel. Diaphragm walls for a new cut and cover road scheme were required. Carillion Piling, in a joint
venture with Intrafor, undertook geotechnical works to the value of £25m.

The largest shaft constructed was called WA2. This shaft was a launch and reception shaft for tunnel boring machines. The shaft dimensions were 55m diameter, 34m deep with a wall thickness of 1.5m. Other diaphragm walls to form a variety of chambers were also constructed on the project.

These diaphragm walls were constructed using a combination of rope grabs and hydraulic milling machines. In addition to the diaphragm walls, continuous flight auger and rotary bored piles were constructed.

Client: Dublin Corporation
Equipment used: Bauer diaphragm wall mill , Rope suspended diaphragm wall grabs, Mait and Llamada piling machine