UNITRACC - Underground Infrastructure Training and Competence Center

Overview of techniques

Definition soil removal / soil displacement techniques

(Image: Soil removal techniques)

Soil removal techniques:

Jacking pipes are jacked either dynamically or statically from a starting shaft to a target shaft. During this process, the soil or rock material loosened by the jacking is transported away, either continuously, in intervals or after the boring is completed [Stein05a].

(Image: Soil displacement techniques)

Soil displacement techniques:
These techniques involve the static or dynamic jacking

Jul 07, 2006

Overview of techniques

Overview of the methods of trenchless installation of cables and pipelines by jacking or drilling

(Image: Overview of the methods of trenchless installation of cables and pipelines by jacking or drilling)

Jul 31, 2008

Overview of techniques

Aug 01, 2008

Advantages compared to the open-cut method of construction

Advantages and disadvantages of trenchless installation

(Image: Pros and cons)

Advantages of Trenchless Construction:

Groundwater lowering is not necessary
Relatively small volume of excavated soil
Only road breaking is necessary at the starting and target pits
Low impact on traffic, resulting in fewer traffic jams and less strain on residents due to exhaust fumes
Less damage to neighboring structures

(Image: Pros and cons)

Disadvantage of Trenchless Technology:

Potentially higher costs due to

Jul 31, 2008

Advantages compared to the open-cut method of construction

Jul 31, 2008

Utility Tunnelling - Introduction

This presentation is part of the series of presentations "Utility Tunnelling" and intends to give an extensive introduction to the topic of trenchless technologies.

Jun 22, 2023

Dokumentationen

Rehabilitation of a DN 400 Concrete Gravity Sewer with a SAERTEX-LINER® MULTI over a Length of 69 m

Rehabilitation of a DN 400 concrete sewer section with “Lining with Cured-In-Place Pipes” (product name: SAERTEX-LINER® MULTI, type S+ Standard). The aim of the rehabilitation measure was the static strengthening and the restoration of the tightness of the old sewer.

Jan 25, 2005

Mathematical Simulation of Pipe Stresses for Difficult Jackings

CoJack

(Image: Presentation of a pipe jacking with an intermediate jacking station)

Jan 25, 2005

Mathematical Simulation of Pipe Stresses for Difficult Jackings

Pipe jacking - definition

In this method, jacking pipes are jacked by pressing-in through the subsoil from a starting shaft to a target shaft with the aid of a jacking station as well as intermediate jacking stations.
Jacking in a straight or curved line path is made possible by means of a steerable shield machine positioned at the head of the first pipe. The spoil excavated at the working face is conveyed to the surface through the jacked pipe string.

(Image: View into …

Jan 25, 2005

Mathematical Simulation of Pipe Stresses for Difficult Jackings

Pipe jacking - technical components

(Image: Attention!)

With reference to the variant used to support the workface or to convey the excavated soil the technical components vary in pipe jacking.

(Image: Schematic presentation of a pipe jacking)

Jan 25, 2005

Mathematical Simulation of Pipe Stresses for Difficult Jackings

Advantages of trenchless technology

Advantages of trenchless technology compared to the open cut method:

Preventing break-up and replacement of road surface
Prevention of soil excavation masses
Minimizing groundwater retention measures
Little impairment to traffic flow especially in inner urban areas
Only short-term noise and emission pollution while excavating the starting and target shafts

(Image: Disadvantages of the open cut method for installing drains and sewers (Part 1) [GSTT])

Jan 25, 2005

Mathematical Simulation of Pipe Stresses for Difficult Jackings

Functions of the shield machine

The duties of the shield machine in pipe jacking are as follows [Scher77a] :

To protect the personnel,
To create the necessary cavity so that the following pipe string can be pressed in with a minimum degree of soil deformation and with the lowest possible skin friction,
To protect the cavity until the jacking pipes can finally carry all the loads and forces,
To secure the working face against collapsing soil and rock as well as groundwater, and

Jan 25, 2005

Mathematical Simulation of Pipe Stresses for Difficult Jackings

Shield machine types - overview

(Image: Overview of shield machine types)

Jan 25, 2005

Mathematical Simulation of Pipe Stresses for Difficult Jackings

Damages in pipe jacking

In jacking processes, extensive and irreparable damages are frequently observed, which is due to irregularities of the subsoil.

Although extensive subsoil investigations can reduce the subsoil risk, failures and damages cannot completely be excluded.

(Image: Attention!)

These are the consequences of damages during pipe jacking:

Insufficient quality of the construction execution
Delay
High costs
Environmental impacts

Jan 25, 2005

Mathematical Simulation of Pipe Stresses for Difficult Jackings

Damages in pipe jacking - statistics

(Image: Distribution of damages in pipe jacking in Germany (source: IFB, Hanover 1993))

Aug 23, 2005

Mathematical Simulation of Pipe Stresses for Difficult Jackings

Pipe jacking technique

Mar 07, 2014

Course

BE-21 Utility Tunnelling

This course includes tutorial services and a final examination. The installation of supply and disposal lines is still mostly performed using the open cut method consisting of digging a trench, laying the pipe under the protection of shoring, and subsequently backfilling the trench. Given the many disadvantages associated with this method along with the growing environmental awareness of the population, it is imperative that trenchless technologies be taken more strongly into account in the planning and construction of pipelines and utility networks. The learning module "Utility tunnelling" is divided into seven lessons, each focusing on a specific topic. The contents of the individual lessons are complemented with a link to more detailed literature. This literature is not relevant to the exam, but serves as a reference for a more in depth look. The module "Utility Tunnelling" ends with a final examination, which references all of the modules content. In order to complete the course successfully, and stress-free within four weeks, we recommend following the following agenda which distributes the different modules evenly over the entire period: 1st week: Module: Introduction, Fundamentals and geotechnical investigations, Pipe jacking (Part 1) 2nd week: Module: Pipe jacking (Part 2), Microtunnelling 3rd week: Module: Jacking pipes, Jacking steering 4th week: Module: Starting and target shafts, Final exam This schedule is only a recommendation, as it is of course up to you when and how you work through the curriculum.

Nov 24, 2004

Technical Books

Rehabilitation and Maintenance of Drains and Sewers

Replacement by the Trenchless Method

Pipe Jacking (Manned Techniques)

(Image: Microtunnel construction - View of the start shaft with main jacking station and reinforced concrete jacking pipe [FI-FBS])

Hydraulic pipe jacking (see ATV-A 125E or DVGW-W 304 [ATVA125:1996]) [Stein85a] [Conra84b] [Hornu89] [Scher77b] [Stein85e] has been available since the turn of the 20th Century as an alternative to the gallery techniques (heading) and the shield tunnelling with segment lining. This method for the case under consideration …

May 18, 2020

Content

Today, supply and discharge lines are still predominantly installed by using the open-cut method: a trench is dug, the lines are installed. Under the protection of an embankment or sheeting and the trench is filled afterwards.

In the face of the numerous disadvantages as well as the citizens' growing environmental consciousness in the future it is urgently necessary to take trenchless technology into account much stronger than until today as an alternative …

May 18, 2020

Utility Tunnelling - Pipe jacking - Part 2

(Image: Simple hand shield - working face with natural support)

Hand shields are non-mechanised open shield machines in which the soil at the working face is loosened by hand using auxiliary tools (pickaxe, spades, shovels or pneumatic hammer). The removal of the spoil is carried out with the aid of conveyor belts, transport carts or tracked conveying buckets (dump trucks).

Examples:

(Image: Hand shield (external diameter 4672) with working …

May 18, 2020

Shield machines with partial excavation by hand - classification

(Table: Classification of hand shields according to the type of working face support)

May 18, 2020

SM-T1 - working face with natural support

May 18, 2020

Utility Tunnelling - Pipe jacking - Part 2

SM-T2 - working face with partial support

(Image: Attention!)With partial support, the surface of the working face is divided into sections and is either supported by means of natural partial support on bench plates (bench (plate) or platform shields) and/or by means of mechanical partial support using breast plates.

(Image: Hand shield with breast plates - working face with mechanical partial support) (Image: Hand shield with benches (Bench shield) - working face with natural partial support) (…

May 18, 2020

Shield machines with partial excavation by hand - area of application

(Image: Attention!)

Shield machines with partial excavation by hand are predominantly used for:

short jacking distances under 50 m
crossings of traffic ways
jacking of an extraordinary cross-section
groundwater-free soil or rock

May 18, 2020