SIST EN 12715:2021

SLOVENSKI STANDARD
oSIST prEN 12715:2019
01-julij-2019
Izvedba posebnih geotehničnih del - Injektiranje
Execution of special geotechnical work - Grouting - Grouting
Ausführung von Arbeiten im Spezialtiefbau - Injektionen - Injektionen
Execution des travaux geotechniques speciaux - Injection - Injection
Ta slovenski standard je istoveten z: prEN 12715
ICS:
93.020 Zemeljska dela. Izkopavanja. Earthworks. Excavations.
Gradnja temeljev. Dela pod Foundation construction.
zemljo Underground works
oSIST prEN 12715:2019 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN 12715:2019

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oSIST prEN 12715:2019


DRAFT
EUROPEAN STANDARD
prEN 12715
NORME EUROPÉENNE

EUROPÄISCHE NORM

May 2019
ICS 93.020 Will supersede EN 12715:2000
English Version

Execution of special geotechnical work - Grouting -
Grouting
Execution des travaux geotechniques speciaux - Ausführung von Arbeiten im Spezialtiefbau -
Injection - Injection Injektionen - Injektionen
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 288.

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, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, 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
© 2019 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 12715:2019 E
worldwide for CEN national Members.

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Contents Page
European foreword . 3
1 Scope . 4
2 Normative references . 4
3 Terms and definitions . 5
4 Information needed for the execution of work . 8
4.1 General. 8
4.2 Specific information . 8
5 Geotechnical investigation . 9
5.1 General. 9
5.2 Specific requirements . 9
5.3 Field grouting tiles and field tests . 10
6 Materials and products . 10
6.1 General. 10
6.2 Grout materials . 10
6.3 Grouts . 11
7 Execution design . 13
7.1 General. 13
7.2 Execution design basis and objectives . 13
7.3 Grouting principles and methods . 14
7.4 Grout . 17
7.5 Grout placement . 18
7.6 Monitoring and control criteria . 20
8 Execution . 20
8.1 General. 20
8.2 Drilling . 21
8.3 Grout preparation. 21
8.4 Grout placement . 22
8.5 Grouting sequences . 24
9 Supervision, testing and monitoring . 24
9.1 General. 24
9.2 Testing . 24
9.3 Monitoring and control . 25
10 Works preparation . 26
10.1 General. 26
10.2 Documents produced on site . 27
11 Special aspects (environment, site safety) . 28
11.1 General. 28
11.2 Health and safety . 28
11.3 Environmental protection . 28
Annex A (informative) Glossary . 30
Annex B (informative) Grout types —Processes and their characterizing . 39
ANNEX C (informative) Measurement of grout parameters . 42
Bibliography . 46

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European foreword
This document (prEN 12715:2019) has been prepared by Technical Committee CEN/TC 288 “Execution
of special geotechnical works”, the secretariat of which is held by AFNOR.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 12715:2000.
The general scope of TC 288 is the standardization of the execution procedures for geotechnical works
(including testing and control methods) and of the required material properties. WG18 has been
charged to revise EN 12715:2000, with the subject area of grouting.
The design, planning and execution of grouting call for experience and knowledge in this specialized
field. The execution phase requires skilled and qualified personnel and the present document cannot
replace the expertise of specialist contractor.
The document has been prepared to complement EN 1997-1, Eurocode 7: Geotechnical design ― Part 1:
General rules and EN 1997-2, Eurocode 7 ― Geotechnical design ― Part 2: Ground investigation and
testing.
Until EN 1997-3 is published, the design of grouting works is not clearly defined. In particular, the
boundary between design under the proposed EN 1997-3 and design as part of the execution of
grouting works has not been determined. This document has, therefore, adopted a distinction between
execution design, i.e. the design of grouting methodology and the other phases of design.
Clause 7 “Execution Design” of this document expands on design only where necessary for the
execution.
This document provides coverage of the construction and supervision requirements for grouting works.
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1 Scope
This document is applicable to the execution, testing and monitoring of geotechnical grouting work.
Grouting for geotechnical purposes (geotechnical grouting) is a process in which the remote placement
of a pumpable material in the ground is indirectly controlled by adjusting its rheological characteristics
and by the manipulation of the placement parameters (pressure, volume and the flow rate).
The following principles and methods of geotechnical grouting are covered by this document:
• displacement grouting (compaction and compensation grouting);
• grouting without displacement of the host material (permeation, fissure/rock grouting, bulk filling).
The principal objectives of geotechnical grouting are:
• the modification of the hydraulic/hydrogeological characteristics the ground;
• the modification of the mechanical properties of the ground;
• the filling of natural cavities, mine workings, voids adjacent to structures;
• inducing displacement to compensate for ground loss or to stabilize and lift footings, slabs and
pavements.
Specialized grouting activities, generally associated with structural and/or emergency works, are not
covered by this document.
The execution, testing and monitoring of jet grouting work is not covered by this document and is
covered by EN 12716.
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 1997-1, Eurocode 7: Geotechnical design — Part 1: General rules
EN 1997-2, Eurocode 7 — Geotechnical design — Part 2: Ground investigation and testing
EN 197-1:2011, Cement — Part 1: Composition, specifications and conformity criteria for Common
cements
EN 197-2, Cement — Part 2: Conformity evaluation.
EN 934-1, Admixtures for concrete, mortar and grout — Part 1: Common requirements
EN 934-3, Admixtures for concrete, mortar and grout — Part 3: Admixtures for masonry Mortar —
Definitions, requirements, conformity, marking and labelling
EN 934-4, Admixtures for concrete, mortar and grout — Part 4: Admixtures for grout for prestressing
tendons — Definitions, requirements, conformity, marking and labelling
EN 934-6, Admixtures for concrete, mortar and grout — Part 6: Sampling, assessment and verification of
the constancy of performance
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EN 480-1, Admixtures for concrete, mortar and grout — Part 1: Test methods. Reference concrete and
reference mortar for testing
EN 480-2, Admixtures for concrete, mortar and grout — Part 2: Test methods. Determination of setting
time
EN 480-4, Admixtures for concrete, mortar and grout — Part 4: Test methods. Determination of bleeding
of concrete
EN 480-5, Admixtures for concrete, mortar and grout — Part 5: Test methods. Determination of capillary
absorption
EN 480-6, Admixtures for concrete, mortar and grout — Part 6: Test methods. Infrared analysis
EN 480-8, Admixtures for concrete, mortar and grout — Part 8: Test methods. Determination of the
conventional dry material content
EN 480-10, Admixtures for concrete, mortar and grout — Part 10: Test methods. Determination of water
soluble chloride content
EN 480-11, Admixtures for concrete, mortar and grout — Part 11: Test methods. Determination of air void
characteristics in hardened concrete
EN 480-12, Admixtures for concrete, mortar and grout — Part 12: Test methods. Determination of the
alkali content of admixtures
EN ISO 22282-2, Geotechnical investigation and testing — Geohydraulic testing — Part 2: Water
permeability tests in a borehole using open systems (ISO 22282-2)
EN ISO 22282-3, Geotechnical investigation and testing — Geohydraulic testing — Part 3: Water pressure
tests in rock (ISO 22282-3)
EN 16228-6, Drilling and foundation equipment. — Safety — Part 6: Jetting, grouting and injection
equipment
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:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
NOTE The definitions given in this chapter cover only the most important terms involved in geotechnical
grouting. Further definitions are given in the glossary in Annex A.
3.1
bulk filling
placement of grout to fill subterranean cavities
3.2
compaction grouting
displacement grouting method which is the injection of a low slump mortar into the soil to
compact/densify it by expansion alone
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3.3
contact grouting
injection of grout into the interface between man-made structures and the ground
3.4
displacement grouting
injection of grout into a host medium in such a manner as to deform, compress, or displace the ground
3.5
effective pressure
pressure governing the flow in the ground, calculated from the sum of all head losses and head gains in
the injection system and the ground
3.6
fissure grouting
injection of grout into fissures, joints, fractures and discontinuities in rock
3.7
grout
pumpable material (suspension, solution, emulsion or mortar), introduced into soil or rock, which
stiffens and sets with time
3.8
grouting pressure
pressure applied during the grouting process and measured at defined locations, usually at the pump or
the borehole collar (also known as “working pressure”)
3.9
hydraulic fracturing
injection of water or grout that creates a new localized fracture in the ground
3.10
hydraulic jacking
injection of water or grout within existing fractures in the ground to enhance the grout spread and
penetrability; also called hydrojacking
3.11
penetration grouting
grout injection of joints or fractures in rock, or pore spaces in soil, without displacing the ground
Note 1 to entry: The term includes permeation (impregnation), fissure and contact grouting.
3.12
permeation grouting
replacement of interstitial water or gas of a porous medium with a grout, also known as “impregnation”
grouting
3.13
non-displacement grouting
injection of grout into a host medium in such a manner as not to deform, compress, or displace the
ground
Note 1 to entry: The term includes penetration grouting and bulk filling.
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3.14
bleed
process by which water forms a separate segregation phase from the grout under gravity or pressure
3.15
stable suspension
ability of a suspension to minimise bleed and segregation and retain its original properties under
pressure
3.16
field grouting trials
field grouting trials are executed in order to define or validate a grouting methodology
3.17
hydraulic binders
all cements and similar products used in aqueous suspensions to produce grout
3.18
fine cement
hydraulic binders or cements that are characterized by a particle size d of less than 40 µm
95
3.19
microfine
hydraulic binders or cements that are characterized by a particle size d of less than 20 µm
95
3.20
ultrafine
hydraulic binders or cements that are characterized by a particle size d of less than 10 µm
95
3.21
admixtures
one or more materials added to the grout or mortar to alter its properties
3.22
mortars
highly particulate grout containing sand and fine aggregates, commonly a concrete with an aggregate
size of less than 4 mm
3.23
split spacing
procedure by which additional grout injection holes are located midway between previously grouted
holes
3.24
sleeved pipe
injection pipe perforated at regular intervals where the perforations are covered externally by sleeves
acting as non-return valves
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4 Information needed for the execution of work
4.1 General
4.1.1 Prior to the execution of the work, all necessary information shall be provided. This information
should include the following, where relevant:
• any legal or statutory restrictions;
• the location of main grid lines for setting out;
• the conditions of structures, roads, services, etc. adjacent to the work, including any necessary
surveys;
• a suitable quality management system, including supervision, monitoring and testing;
• the geometry of the site (boundary conditions, topography, access, slopes, headroom restrictions,
etc.);
• the existing underground structures, services, known contaminations, and archaeological
constraints;
• the environmental restrictions, including noise, vibration, pollution; and
• the future or ongoing activities such as dewatering, tunnelling, deep excavations.
4.2 Specific information
4.2.1 The specific information shall cover, where relevant:
• execution specifications;
• previous use of the site;
• adjacent foundations (types, loads and geometry);
• geotechnical information and data as specified in Clause 5;
• presence of obstructions in the ground (old masonry, anchors, concrete, blocks and boulders etc.);
• presence of headroom restrictions;
• presence of archaeological remains;
• presence of natural and/or manmade cavities (mines, etc.);
• presence of polluted ground and type extent and degree of pollution;
• any specific requirements for the grouting works, in particular those pertaining to tolerances,
quality of materials, methods and frequency of testing;
• where available, previous experience with grouting works on or adjacent to the site;
• proposed adjacent enabling or advance works that may affect the grouting works;
• functional requirements for instrumentation and monitoring of potentially affected structures;
• necessity, extent, procedure and content for any survey on the conditions of structures, roads,
services, etc. adjacent to the works area.
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4.2.2 The survey shall be carried out and be available prior to the commencement of the work, and its
conclusions shall be used to define the threshold values for any movement which may affect adjacent
structures by the works area constructions.
4.2.3 Any additional or deviating requirements to this document shall be established and agreed upon
before the commencement of the work and the quality control system shall be suitably amended.
5 Geotechnical investigation
5.1 General
5.1.1 The geotechnical investigation shall fulfil the requirements of EN 1997-2 and the relevant
national documents.
5.2 Specific requirements
5.2.1 Relevant experience of the execution of comparable grouting works under similar conditions
and/or in the vicinity of the site should be taken into account when determining the extent of site
investigation (reference to relevant experience is permitted if appropriate means of verification were
taken).
5.2.2 The geotechnical investigation report shall be sufficient and available to allow for the reliable
execution of the grouting works.
5.2.3 If during grouting the ground conditions differ from those in the geotechnical investigation
report, this shall be reported.
5.2.4 For the execution of grouting works, the ground investigation report should contain the
following specific information:
• the relevant physical and chemical characteristics of the ground and groundwater;
• the presence of any anisotropies or permeable horizons which could influence the grouting works;
• the orientation, frequency, and aperture of rock joints and the composition and nature of any infill
material;
• the location and nature of filled or open cavities;
• the presence of obstructions that require special drilling and grouting methods or equipment;
• the presence and characteristics of ground that is likely to loosen, soften or become unstable,
dissolve, collapse or swell as a result of drilling or grouting;
• the presence of strata with high groundwater velocities and permeabilities.
5.2.5 Where relevant, the following specific drilling information should be recorded:
• location and cause of core losses;
• unstable zones and stabilization measures taken;
• water level at the beginning and end of a run, zones of water loss and gain, measurements of return
water, water colour and changes in colour;
• recording of drill parameters in the case of destructive boreholes;
• rate of advance.
5.2.6 Permeability testing shall be done in accordance with EN ISO 22282.
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5.3 Field grouting tiles and field tests
5.3.1 Field grouting trials should be executed where initial site investigations and local or comparable
experience is insufficient to support or justify the effectiveness of the grouting project.
NOTE Some indication of in situ groutability can be obtained by permeating reconstituted soil samples with
trial grouts under laboratory conditions.
5.3.2 The trials should provide information on borehole spacing, grout type, procedure and
parameters.
5.3.3 Detailed records shall be kept of each operation performed during the grouting trials.
6 Materials and products
6.1 General
6.1.1 All grout components and grouts shall comply with the specifications for the works.
NOTE Where relevant, EN or national standards and/or EN or national regulations could apply.
6.1.2 The suitability of the grout constituents and their combination with the ground shall be
considered and investigated if necessary.
6.1.3 Once established, the sources of grout materials shall not be changed without prior compliance
verification or testing.
6.2 Grout materials
6.2.1 Cement and hydraulic binders
6.2.1.1 Cements shall comply with EN 197-1 and EN 197-2. Cements that do not comply with
EN 197‑1:2011, Table 1 may be used if considered acceptable for the grouting purpose envisaged.
6.2.1.2 Testing of cements and other binders shall be in accordance with their appropriate method.
6.2.1.3 When selecting the type of hydraulic binder for grout, its grain size distribution shall be
evaluated in relation to the dimensions of the rock apertures or interstitial voids of the ground to be
treated.
6.2.1.4 Pozzolans, blast furnace slag, silica fume and fly ash from thermal power plants or any other
reactive material may be used in grouts.
6.2.2 Clay materials
6.2.2.1 Natural clays, activated or modified bentonites can be added to cement-based grouts in
order to reduce bleeding and/or filtration under pressure, to vary the viscosity and cohesion (yield) of
the grout, or to improve the pumpability and/or penetrability of the grout.
6.2.2.2 The mineralogy, particle size, water content, and Atterberg limits of the clay should be
known
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6.2.3 Sands, gravels and fillers
6.2.3.1 Sands, gravels and inert fillers may be added to cement grouts or clay suspensions as
bulking agents or as a means of varying the consistency of the grout, its resistance to wash-out, or its
mechanical strength and deformability.
6.2.3.2 The grain size distribution of sands, gravels and fillers shall be known.
6.2.4 Water
6.2.4.1 Unless potable water is used for grouting, its chemical suitability shall be verified.
6.2.4.2 Sea water can be used provided that the properties of the grout mix are not impaired.
6.2.5 Chemical products and admixtures
6.2.5.1 The effects of all chemical products and their by-products, including the effect of time,
resulting from the reaction of the chemical products with other components of the grout or with the
surrounding ground shall be considered and comply with relevant environmental legislation.
6.2.5.2 Admixtures may be added to the grout to modify its properties and to control its parameters
such as viscosity, setting time, stability, strength, resistance, cohesion and permeability after placement
6.2.5.3 Admixtures to grout such as superplasticizers, water retaining agents, air entrainers and
others shall be subject to Parts 1, 3, 4 and 6 of EN 934 and EN 480-1 to EN 480-12.
6.3 Grouts
6.3.1 General
6.3.1.1 Grouts are classified as:
• suspensions: either particulate or colloidal (nano-particles);
• solutions: either true or colloidal (large molecules);
• mortars.
6.3.1.2 The following intrinsic properties shall be considered when choosing a grout:
• rheology (viscosity, cohesion, etc.), setting time, stability;
• particle size, if applicable;
• strength and durability;
• toxicity.
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6.3.2 Suspensions
6.3.2.1 The suspensions are characterized by the following properties:
• water/solid and/or binder ratio;
• grain size distribution;
• rate of segregation and bleeding;
• stability under pressure filtration;
• rheology and it's evolution with time.
6.3.2.2 The tendency of suspended solids to flocculate shall be taken into account, particularly
when using microfine/ultra-fine cements.
6.3.2.3 The tendency of solids in suspension to settle in water due to gravity forces and their
tendency to bleed under pressure, shall be considered in relation with the nature and properties of the
host medium.
6.3.2.4 Clay suspensions should be prepared so that the clay particles are thoroughly deflocculated
and hydrated before injecting.
6.3.3 Solutions
6.3.3.1 After setting, some types of grouts are not stable with time, and their use should be
assessed.
6.3.3.2 The effect of syneresis on the properties of the treated ground and on the environment,
particularly their long-term effect, shall be evaluated prior to treatment.
6.3.3.3 The
...