Pipe jacking is the microtunnelling method where a pipe is jacked into the microtunnel immediately behind the microtunnelling head to ensure full ground support at all times. Generally the difference between the OD of the pipe and the microtunnel diameter is approximately 10 – 25mm.

Microtunneling Pipejack Pezzimenti

Pipejacking a reinforced concrete jacking pipe. 

Microtunneling Pipejacking load steel jacking pipe ready for icrotunneling

Pipejacking Steel Casings

Microtunnelling Pipejack GRP Pipe

Pipejacking GRP Jacking Pipes

Pipejacking Microtunneling Methods

There are 3 primary outcomes for all microtunneling and pipe installations. These are the

  1. Free Pipe – Carrier Pipe is grouted into a microtunneling where the ground is self supporting.
  2. Close Fit Pipe– Carrier Pipe is also the Casing Pipe. Use for projects where the gap between Pipe OD and Microtunnel ID is less than 25mm, and;
  3. Pipe-in-a-Pipe – A carrier Pipe sits within an Outer Casing Pipe.

The Pipejacking Microtunneling method can achieve the Close Fit Pipe and Pipe in a Pipe outcomes as outlined below.

Microtunneling Pipejack to achieve close fit pipe

Close Fit Pipe – Pipejacking Method

Step 1. The ground has been determined as not self-supporting. Jacking pipes are jacked behind the microtunnelling head. For Sewer lines, GRP jacking pipes act as the carrier pipes. For Stormwater lines, GRP and / or concrete pipes act as the carrier pipe.

Microtunneling using Pipejack Method to Achieve Pipe in A pipe

Pipe in a Pipe – Pipejacking Method

Step 1. The ground has been determined as not self-supporting, requiring additional ground support during microtunneling. The selected Casing Pipes are jacked behind the microtunnelling head. Step 2. The Carrier Pipe is inserted into the Casing Pipe and the annular space grouted.

Pipejacked Projects

Pezzimenti Tunnelbore has completed over 300 Pipejacking Projects successfully for the water industry alone throughout the Sydney Region. View a selection of projects which include pipejacked microtunnelling.

Gundagai Culvert Replacement Pezzimenti Feature


Wyee Microtunnelling Pezzimenti Feature


Pezzimenti Tunnelbore Gladstone Feature


Rileys Creek Pezzimenti Microtunnelling Feature Image

Rileys Creek

Eastern Creek Microtunnelling beneath M7 Highway feature

Eastern Creek

Mount Druitt Pezzimenti TUnnelbore Microtunnelling Feature

Mount Druitt