oSIST prEN 12889:2020

Trenchless construction and testing of drains and sewers

This document is applicable to the trenchless construction, trenchless replacement techniques and testing of new drains and new sewers in the ground usually operating as gravity or pressure pipelines, formed using prefabricated pipes and their joints.
Renovation techniques for existing pressure and non-pressure systems are not covered by this document.
Methods of trenchless construction include:
-   manned and unmanned techniques;
-   steerable and non-steerable techniques.
Mining or tunnelling (e.g. in situ construction or the use of prefabricated segments) are not covered by this document although some parts may apply to these methods.
Requirements for associated pipeline installation work other than trenchless construction, e.g. for manholes and inspection chambers, are not covered by this document and are specified in EN 1610. This also applies to pipes that are subsequently installed within entry and exit shafts/pits.

Grabenlose Verlegung und Prüfung von Abwasserleitungen und -kanälen

Dieses Dokument ist anwendbar auf grabenlose Verlegungs  und Erneuerungsverfahren sowie die Prüfung neuer Abwasserleitungen und  kanäle im Boden mit vorgefertigten Rohren und deren Verbindungen, die üblicherweise als Freispiegel  oder Druckrohrleitungen betrieben werden.
Renovierungsverfahren für vorhandene Druckrohrleitungen und drucklose Leitungen sind nicht Gegenstand dieser Europäischen Norm.
Die Methoden zur grabenlosen Verlegung umfassen:
-   bemannte und unbemannte Verfahren;
-   steuerbare und nichtsteuerbare Verfahren.
Bergmännische Bauverfahren und Tunnelbauverfahren (z. B. In Situ Bauverfahren oder die Verwendung vorgefertigter Segmente) sind nicht Gegenstand dieses Dokuments, obwohl einzelne Festlegungen gegebenenfalls auf diese Verfahren anwendbar sind.
Wenn bei der Ausführung grabenloser Baumaßnahmen auch nicht grabenlose Rohrverlegungsarbeiten anfallen, z. B. im Zusammenhang mit Schächten und Inspektionsöffnungen, sind diese nicht Gegenstand dieses Dokuments, sondern in EN 1610 festgelegt. Dies gilt auch für Rohre, die nachfolgend in Start  und Zielschächten bzw. Ein  und Ausstiegen eingebaut werden.

Mise en oeuvre sans tranchée et essais des branchements et collecteurs d'assainissement

Le présent document s’applique aux techniques de construction et de remplacement sans tranchée, ainsi qu’aux essais de collecteurs et branchements neufs, enterrés, fonctionnant habituellement comme des canalisations à écoulement libre ou sous pression, formées de tuyaux préfabriqués et de leurs assemblages.
Les techniques de rénovation des systèmes sous pression et sans pression existants ne sont pas couvertes par le présent document.
Les méthodes de mise en œuvre sans tranchée comprennent :
- les techniques avec ou sans intervention humaine ;
- les techniques avec ou sans guidage.
Les forages miniers ou les méthodes d’exécution des tunnels (par exemple, la construction in situ ou l’utilisation de voussoirs préfabriqués) ne sont pas couverts par le présent document, bien que certaines parties puissent s’appliquer à ces méthodes.
Les exigences relatives à la mise en œuvre des ouvrages annexes autres que la construction sans tranchée, par exemple pour les regards de visite et boîtes d’inspection ou de branchement, ne sont pas couvertes par le présent document et sont spécifiées dans l’EN 1610. Ceci s’applique également aux tuyaux qui sont installés ultérieurement dans les puits d’entrée et de sortie.

Izvedba in preskušanje kanalov in drenaž brez izkopa

General Information

• Status: Not Published
• Public Enquiry End Date: 19-Jul-2020
• ICS: 23.040.05 - Pipeline and its parts for external sewage systems
• ICS: 91.140.80 - Drainage systems
• ICS: 93.030 - External sewage systems
• Technical Committee: IOVO - Water supply and waste water engineering
• Current Stage: 4020 - Public enquire (PE) (Adopted Project)
• Start Date: 08-Jun-2020
• Due Date: 26-Oct-2020
• Completion Date: 10-Aug-2020
• Directive: 305/2011 - Regulation (eu) No 305/2011 of the European Parliament and of the Council of 9 march 2011 laying down harmonised conditions for the marketing of construction products and repealing council directive 89/106/eec
• Directive: 93/38/EEC - Procurement procedures of entities operating in the water, energy, transport and telecommunications sectors
• Mandate: M/BC/CEN/88/15 - Standardization request to CEN/CENELEC in the field of Water supply, drainage and sewerage
• Ref Project: prEN 12889 - Trenchless construction and testing of drains and sewers

RELATIONS

• Revised: SIST EN 12889:2000 - Trenchless construction and testing of drains and sewers
• Effective Date: 01-Jul-2020

Standards Content (sample)

SLOVENSKI STANDARD
oSIST prEN 12889:2020
01-julij-2020
Izvedba in preskušanje kanalov in drenaž brez izkopa
Trenchless construction and testing of drains and sewers
Grabenlose Verlegung und Prüfung von Abwasserleitungen und -kanälen
Mise en oeuvre sans tranchée et essais des branchements et collecteurs
d'assainissement
Ta slovenski standard je istoveten z: prEN 12889
ICS:
91.140.80 Drenažni sistemi Drainage systems
93.030 Zunanji sistemi za odpadno External sewage systems
vodo
oSIST prEN 12889:2020 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN 12889:2020
DRAFT
EUROPEAN STANDARD
prEN 12889
NORME EUROPÉENNE
EUROPÄISCHE NORM
May 2020
ICS 23.040.05; 93.030 Will supersede EN 12889:2000
English Version
Trenchless construction and testing of drains and sewers
Mise en oeuvre sans tranchée et essais des Grabenlose Verlegung und Prüfung von
branchements et collecteurs d'assainissement Abwasserleitungen und -kanälen

This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee

CEN/TC 165.

If this draft becomes a European Standard, CEN members are bound to comply with the CEN/CENELEC Internal Regulations

which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

This draft European Standard was established by CEN in three official versions (English, French, German). A version in any other

language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC

Management Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,

Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,

Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and

United Kingdom.

Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are

aware and to provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without

notice and shall not be referred to as a European Standard.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels

© 2020 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 12889:2020 E

worldwide for CEN national Members.
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Contents Page

European foreword ....................................................................................................................................................... 4

1 Scope .................................................................................................................................................................... 5

2 Normative references .................................................................................................................................... 5

3 Terms and definitions ................................................................................................................................... 5

4 General ................................................................................................................................................................ 7

4.1 Technical principles ....................................................................................................................................... 7

4.2 Safeguarding design decisions ................................................................................................................... 7

5 Construction components and materials ............................................................................................... 8

5.1 General ................................................................................................................................................................ 8

5.2 Pipes and joints ................................................................................................................................................ 8

5.3 Manholes and inspection chambers ......................................................................................................... 8

5.4 Delivery, handling and transportation on site ..................................................................................... 8

5.5 Storage ................................................................................................................................................................ 8

5.6 Other materials ................................................................................................................................................ 9

6 Techniques ........................................................................................................................................................ 9

6.1 Classification ..................................................................................................................................................... 9

6.2 Unmanned techniques ................................................................................................................................ 11

6.2.1 General ............................................................................................................................................................. 11

6.2.2 Non-steerable techniques ......................................................................................................................... 11

6.2.3 Steerable techniques................................................................................................................................... 18

6.3 Manned techniques ..................................................................................................................................... 25

6.3.1 General ............................................................................................................................................................. 25

6.3.2 Non-steerable techniques ......................................................................................................................... 26

6.3.3 Steerable techniques................................................................................................................................... 26

6.3.4 Other manned techniques ......................................................................................................................... 29

7 Requirements of planning and construction ..................................................................................... 29

7.1 General ............................................................................................................................................................. 29

7.2 Basic evaluation, design and construction planning ....................................................................... 29

7.2.1 General ............................................................................................................................................................. 29

7.2.2 Survey of existing structures and systems .......................................................................................... 30

7.2.3 Subsoil and groundwater .......................................................................................................................... 30

7.2.4 Minimum clear dimensions ...................................................................................................................... 32

7.2.5 Subsidence, heaves, cover ......................................................................................................................... 32

7.2.6 Layout of the line .......................................................................................................................................... 32

7.2.7 Tolerances ...................................................................................................................................................... 32

7.2.8 Starting, intermediate and target pits .................................................................................................. 33

7.2.9 Working face support ................................................................................................................................. 33

7.2.10 Additional measures in water bearing subsoil ................................................................................. 33

7.2.11 Obstacles ......................................................................................................................................................... 34

7.2.12 Soil conditioning ........................................................................................................................................... 34

7.2.13 Structural calculation ................................................................................................................................. 34

7.2.14 Construction site arrangement ............................................................................................................... 34

7.3 Work preparation and construction ..................................................................................................... 34

7.3.1 General ............................................................................................................................................................. 34

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7.3.2 Starting, intermediate and target pits ................................................................................................... 35

7.3.3 Exit and entry processes ............................................................................................................................ 35

7.3.4 Launch and reception shafts ..................................................................................................................... 35

7.3.5 Overcut ............................................................................................................................................................. 35

7.3.6 Recording and logging of jacking parameters .................................................................................... 35

7.3.7 Support of the working face ...................................................................................................................... 36

7.3.8 Lubricant and supporting medium ........................................................................................................ 36

7.4 Avoidance of damage ................................................................................................................................... 36

8 Inspection and testing of pipelines after installation ...................................................................... 37

8.1 General ............................................................................................................................................................. 37

8.2 Visual inspection ........................................................................................................................................... 37

8.3 Leaktightness ................................................................................................................................................. 37

9 Qualifications ................................................................................................................................................. 38

Annex A (informative) Abstract from Directive 2014/25/EU of the European Parliament

and of the Council of 26 February 2014 on procurement by entities operating in the

water, energy, transport and postal services sectors and repealing

Directive 2004/17/EC (Text with EEA relevance) ............................................................................ 39

Annex B (informative) Planning information for the application of different systems ................... 40

Annex C (informative) Typical ranges of application regarding diameters and lengths in

suitable soil ..................................................................................................................................................... 48

Annex D (informative) Typical ranges of application for selected trenchless techniques

regarding diameters and lengths in suitable soils ........................................................................... 50

Bibliography ................................................................................................................................................................. 51

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European foreword

This document (prEN 12889:2020) has been prepared by Technical Committee CEN/TC 165 “Waste

water engineering”, the secretariat of which is held by DIN.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 12889:2000.
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1 Scope

This document is applicable to the trenchless construction, trenchless replacement techniques and

testing of new drains and new sewers in the ground usually operating as gravity or pressure pipelines,

formed using prefabricated pipes and their joints.

Renovation techniques for existing pressure and non-pressure systems are not covered by this

document.
Methods of trenchless construction include:
— manned and unmanned techniques;
— steerable and non-steerable techniques.

Mining or tunnelling (e.g. in situ construction or the use of prefabricated segments) are not covered by

this document although some parts may apply to these methods.

Requirements for associated pipeline installation work other than trenchless construction, e.g. for

manholes and inspection chambers, are not covered by this document and are specified in EN 1610.

This also applies to pipes that are subsequently installed within entry and exit shafts/pits.

2 Normative references

The following documents are referred to in the text in such a way that some or all of their content

constitutes requirements of this document. For dated references, only the edition cited applies. For

undated references, the latest edition of the referenced document (including any amendments) applies.

EN 476, General requirements for components used in drains and sewers
EN 752, Drain and sewer systems outside buildings – Sewer system management
EN 805, Water supply – Requirements for systems and components outside buildings

EN 1295-1, Structural design of buried pipelines under various conditions of loading – Part 1: General

requirements
EN 1610:2015, Construction and testing of drains and sewers
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

— ISO Online browsing platform: available at https://www.iso.org/obp
— IEC Electropedia: available at http://www.electropedia.org/
3.1
cutting head

tool or system of tools on a common support, which excavates at the face of a bore

Note 1 to entry: The term usually applies to mechanical methods of excavation.
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3.2
expander

tool which enlarges a bore by displacement of the surrounding ground rather than by excavation

3.3
gravity pipeline

pipeline where flow is caused by the force of gravity and where the pipeline is designed usually to

operate partially full
3.4
overbreak

extent by which the excavated void including accidental ground losses initially exceeds the outside

dimension of the pipe
3.5
overcut

annular space around the pipe deliberately created by using a cutting head or shield of greater

dimension than the outside dimension of the pipe
3.6
pipe jacking

system of directly installing pipes behind a cutting head and/or shield, by hydraulic jacking from a drive

shaft, such that the pipes form a string in the ground
3.7
reamer

cutting head attached to the end of a drill string or pilot rod to enlarge the pilot diameter during a pull-

back or pushing operation, to enable a pipe or pipes to be installed
3.8
renovation

work incorporating all or part of the original fabric of the pipeline by means of which its current

performance is improved
[SOURCE: EN 15885:2018, 3.2]
3.9
replacement

construction of a new pipeline, on or off the line of an existing pipeline, where the function of the new

pipeline system incorporates that of the old
[SOURCE: EN 15885:2018, 3.4]
3.10
spoil
material excavated and removed in the course of installation
3.11
trenchless construction technique
technique for constructing pipelines in the ground without opening trenches
3.12
manned technique

technique involving the use of personnel working in the excavated bore during installation

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3.13
unmanned technique

technique avoiding the use of personnel working in the excavated bore during installation

4 General
4.1 Technical principles

Pipelines, manholes and inspection chambers are engineering structures in which the combined

performance of construction components, bedding and fill or the surrounding ground constitutes the

basis for stability and safety in operation. The pipes, fittings and components for jointing supplied,

together with the work carried out at site, are all important factors in achieving a structure with

adequate performance over the intended service life.

The network owner and the planner shall coordinate the extent and the requirements of the

engineering services to be rendered for the individual case.

The pipeline and any associated structures shall be designed during planning in accordance with

EN 1295-1 and EN 752 as applicable to ensure it is capable of carrying all foreseeable imposed and

operational loads with a sufficient level of safety.

A procedure shall be established for the resolution of technical questions, agreement and recording of

changes to design decisions made during construction.

Additionally other local or national regulations may apply, e.g. concerning health and safety, pavement

installation, tolerances for deviation in line and level and requirements for leaktightness testing.

4.2 Safeguarding design decisions

In the execution of the work it shall be ensured that the decisions made in the design are complied with

or adapted to changed conditions.

The design decisions may be affected by variation of any of the following which should be checked

during installation:
— pipe support;
— soil conditions and soil types;
— construction traffic and assumptions concerning temporary loads;
— ground water level;

— existing infrastructure in the same proximity (e.g. pipelines, cables, structures);

— settlement and heave;
— deflection;
— deviation from line;
— pipe type, strength or class.
NOTE The above list is not exhaustive.
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5 Construction components and materials
5.1 General

Construction components and materials shall conform to European Standards. In the absence of these,

the components and materials shall comply with design requirements and EN 476.
All written instructions of the manufacturer shall be complied with.
5.2 Pipes and joints

Installation shall not commence before the following criteria have been agreed between the designer

and installer. These may be obtained from appropriate product standards or from the pipe

manufacturer:
— internal pipe diameter;
— external pipe diameter;
— pipe length;
— tolerances on dimensions;
— permissible jacking load or pulling force;
— type and performance of joints;
— longitudinal flexibility (acceptable bending radius or angular deflection).
5.3 Manholes and inspection chambers

Manholes and inspection chambers shall comply with the design. Prefabricated components shall be

assembled and installed according to the instructions of the manufacturer and the designer.

5.4 Delivery, handling and transportation on site

Construction components and materials shall be inspected on delivery to ensure that they are

appropriately marked and comply with the design requirements.

Any handling or transportation instructions from the manufacturer shall be complied with.

Products shall be examined both on delivery and immediately prior to installation to ensure that they

are free from damage and in accordance with the relevant product standard.
5.5 Storage

Any instructions from the manufacturer and the requirements of the appropriate product standards

shall be complied with.

Construction components and materials should be stored in such a manner to keep them clean and

avoid contamination or degradation, for example elastomeric jointing components should be kept clean

and be protected from sources of ozone (e.g. electrical equipment), sunlight and oil, where necessary.

Pipes shall be secured to prevent rolling. Excessive stacking heights should be avoided so that pipes in

the lower part of the stacks are not overloaded. Stacks of pipes shall not be placed close to open

trenches.

Pipes with protective coatings shall be stored where necessary, on supports which keep them clear of

the ground to avoid damage to coatings and joints. All pipes should be stored on supports in very cold

weather to avoid freezing to the ground.
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5.6 Other materials

The mechanical and environmental impact of other materials used during the construction process on:

— pipeline,
— surrounding soil,
— surface water and groundwater
shall be considered by the designer.
Consideration shall also be given to the following:
— production/origin;
— treatment and storage;
— leaching;
— cleanliness.
6 Techniques
6.1 Classification

Pre-fabricated pipes are jacked or pulled into the ground between the starting pit and the target pit. The

soil is either displaced and/or excavated at the working face and is mechanically, hydraulically or

pneumatically transported to the starting or target pit or in some techniques may be removed from the

pipe as an earth core after completion. It is distinguished between manned and unmanned processes.

With reference to the required accuracy, non-steerable or steerable jacking processes are selected.

The selection of the process depends on:
— the planned/given jacking pipe;
— the required positional precision; the client/ planner shall define it;

— the proximity to neighbouring utility services and sewers and other structures and systems;

— the external diameter;
— the jacking distance;
— the subsoil conditions;
— the groundwater conditions;
— the minimum depth of cover and
— the clear dimensions necessary for employing personnel inside the pipe string.

A schematic classification of trenchless techniques is given in Figure 1, representing techniques

available at the time of publication of this European Standard.
The techniques are described and illustrated in 6.2 and 6.3.

Planning information for the application of different systems are given in Annex B, Table B.1.

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Figure 1 — Classification of trenchless techniques
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6.2 Unmanned techniques
6.2.1 General

Unmanned techniques do not require employment of personnel inside the pipe string and in the jacking

station for jacking. Steerable Horizontal Directional Drilling methods (HDD) as well as methods for

trenchless replacement of pipelines on the same line represent unmanned techniques that are related

to pipe jacking. The prerequisite for a temporary employment of personnel inside the pipe string are

described in 7.2.4.
6.2.2 Non-steerable techniques
6.2.2.1 General

The accuracy of non-steerable techniques in new construction is influenced by the subsoil (e.g. soil

type), intrusions and stratifications, the type of pipe joint, the external pipe diameter and the pipe wall

thickness and other things, and decreases disproportionately with the jacking distance. Therefore the

use of these methods for pipelines that require an exact position is restricted because of operational

reasons. Damage to adjacent systems has to be excluded by ensuring sufficient clearance. Thus, during

new construction suitable methods should be used to determine the position during jacking.

For use in water-bearing strata, additional measures such as groundwater retention may become

necessary.

Table C.1 contains empirical values for the area of application of the listed unmanned, non-steerable

techniques. The in situ subsoil conditions and project-specific boundary conditions shall always be

taken into consideration.
6.2.2.2 Soil displacement techniques
6.2.2.2.1 General
All listed techniques require soil that is displaceable.
6.2.2.2.2 Impact moling

Impact moling is a technique, generally considered to be non-steerable, using a pneumatic powered

torpedo shaped device, known as a mole (see Figure 2). This incorporates a reciprocating internal

hammer impacting on the back of a nose cone which in some cases can move independently of the main

body. The friction between the main body and the ground enables the nose cone to move forward at

each hammer blow, while the length of the main body keeps the mole on line. There are several designs

of nose cone, which claim to give better penetration, or to be less susceptible to being pushed off line by

lumps of stone.

Because the excavated material has to be forced out into the surrounding ground, this technique is

confined to small pipe diameters. The pipe is generally pulled in behind the mole, or can be pulled back

as the mole is reversed out. The piping is either done simultaneously or in a sufficiently stable soil by

subsequent pulling or pushing in. A shrinking of the excavated diameter of the cavity by 5 % to 15 %

has to be taken into account. Up to an external diameter of 63 mm, the technique can be used in a

steerable manner.
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Key
1 air compressor
2 starting pit
3 new (discrete) pipe
4 impact mole
5 planned route
6 target pit
Figure 2 — Example of impact moling
6.2.2.2.3 Pipe ramming with a pipe closed at its leading end

Pipe ramming with a pipe closed at its leading end is a technique of forming a bore by driving a steel

casing with a closed end using a percussive hammer (see Figure 3). The soil is displaced by the leading

closed pipe end.

When dimensioning the pipes for trenchless installation with pipe ramming, additional dynamic loads

have to be taken into account. Product pipes with cement mortar lining and/or cement mortar coating

shall not be installed by pipe ramming.
Key
1 starting pit
2 ramming hammer
3 pipe
4 air compressor
5 end cone
6 planned route
7 target pit
Figure 3 — Example of pipe ramming with a pipe closed at its leading end
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6.2.2.2.4 Rod pushing with an expander

Pushing a pilot rod displaces the soil. After having arrived in the target pit, the rod is connected to a

conical pushing head or a soil displacement hammer, which is also connected to the host or product

pipes. Afterwards, the entire string is pulled back (see Figure 4).

The upper part of Figure 4 shows the installation of pilot rod and initial displacement of soil. The lower

part shows the installation of the pipe and further displacement of soil.
The expander may be in the form of a displacement cone or a reamer.
Key
1 starting pit 5 target pit
2 ram system 6 rod
3 hydraulic pump 7 expander
4 pilot rod 8 pipe
Figure 4 — Example of the process of rod pushing with an expander
6.2.2.2.5 Pipe bursting

Replacement is done by bursting or splitting the existing pipe, and displacing it into the surrounding

ground, while simultaneously pulling in a new continuous or discrete pipe, of the same or larger

diameter.

A bursting head with a cone with or without fixed blades is generally used for brittle pipe materials

such as clay, grey cast iron or fibre cement, whereas a splitting head with cutting discs is generally used

for non-brittle pipe materials such as ductile iron, steel or plastics. Both types of head embody an

expansion cone to displace the existing burst or split pipe into the surrounding ground and form a bore

for the new pipe.

Additional measures may become necessary in water-bearing soils. The new pipe shall be dimensioned

in accordance with the structural calculation.
Methods used are static
...