sprayed concrete
TRANSCRIPT
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
a
Date: 25 June 2002
Origin: European
Latest date for receipt of comments: 2002.09.30 Project no.: 2002/01893
Responsible committee: B/517/1 Concrete Production And Testing
Interested committees: B/2; B/11; CB/1; B/517; B/525/2
Title: Draft EN 14487: PART 1 Sprayed Concrete
Part 1: Defintitions, Specifications and Conformity
Supersession information: If you are aware of a current national standard which may be affected, please notify thesecretary (contact details below).
WARNING: THIS IS A DRAFT AND MUST NOT BE REGARDED OR USED AS A BRITISH STANDARD.THIS DRAFT IS NOT CURRENT BEYOND 2002.09.30.
This draft is issued to allow comments from interested parties; all comments will be given consideration prior topublication. No acknowledgement will normally be sent. See overleaf for information on commenting.
No copying is allowed, in any form, without prior written permission from BSI except as permitted under the Copyright,Designs and Patent Act 1988 or for circulation within a nominating organization for briefing purposes. Electroniccirculation is limited to dissemination by e-mail within such an organization by committee members.
Further copies of this draft may be purchased from BSI Customer Services, Tel: +44(0) 20 8996 9001 or [email protected]. British, International and foreign standards are also available from BSI Customer Services.
British Standards on CD or Online are available from British Standards Publishing Sales Limited.
Tel: 01344 404409 or email [email protected].
Information on the co-operating organizations represented on the committees referenced above may be obtained fromthe responsible committee secretary.
Cross-references
The British Standards which implement International or European publications referred to in this draft may be found viathe British Standards Online Service on the BSI web site http://www.bsi-global.com.
Direct tel: 020 8996 7603Responsible Committee Secretary: Miss A Attra (BSI)
E-mail: [email protected]
Draft for Public Comment
Head Office389 Chiswick High RoadLondon W4 4AL
Telephone: +44(0)20 8996 9000Fax: +44(0)20 8996 7001
Form 36Version 6.1
DPC: 02/104236 DC
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
b
Introduction
This draft standard is based on European discussions in which the UK took an active part. Your comments on thisdraft are welcome and will assist in the preparation of the consequent British Standard. If no comments are receivedto the contrary, then the UK will approve this draft and implement it as a British Standard. Comment is particularlywelcome on national, legislative or similar deviations that may be necessary.
Even if this draft standard is not approved by the UK, if it receives the necessary support in Europe, the UK will beobliged to publish the official English Language text unchanged as a British Standard and to withdraw any conflictingstandard.
UK Vote
Please indicate whether you consider the UK should submit a negative (with reasons) or positive vote on this draft.
SubmissionThe guidance given below is intended to ensure that all comments receive efficient and appropriate attention by theresponsible BSI committee. Annotated drafts are not acceptable and will be rejected.
All comments must be submitted, preferably electronically, to the Responsible Committee Secretary at the addressgiven on the front cover. Comments should be compatible with Version 6.0 or Version 97 of Microsoft® Word forWindows™, if possible; otherwise comments in ASCII text format are acceptable. Any comments not submittedelectronically should still adhere to these format requirements.
All comments submitted should be presented as given in the example below. Further information on submittingcomments and how to obtain a blank electronic version of a comment form are available from the BSI web site at:
http://www.bsi-global.com/Standards+Development/Drafts/index.xalter
Date Document
NationalCommittee
Clause/subclause
Paragraph/Figure/ Table
Type of comment
(General/technical/editorial)
COMMENTS Proposed change OBSERVATIONS OFTHE SECRETARIAT
3.1 1st definition Editorial Definition is ambiguous andneeds clarifying.
Amend to read ‘... so thatthe mains connector towhich no connection ...’
6.4 § 2 Technical The use of the UVphotometer as an alternativecannot be supported asserious problems have beenencountered in its use in theUK.
Delete reference to UVphotometer.
Microsoft and MS-DOS are registered trademarks, and Windows is a trademark of Microsoft Corporation.
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
EUROPEAN STANDARD
NORME EUROPÉENNE
EUROPÄISCHE NORM
DRAFTprEN 14487-1
June 2002
ICS
English version
Sprayed concrete - Part 1: Definitions, specifications andconformity
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee CEN/TC 104.
If this draft becomes a European Standard, CEN members are bound to comply with the CEN/CENELEC Internal Regulations whichstipulate 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 languagemade by translation under the responsibility of a CEN member into its own language and notified to the Management Centre has the samestatus as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece,Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom.
Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without notice andshall not be referred to as a European Standard.
EUROPEAN COMMITTEE FOR STANDARDIZATIONC OM ITÉ EUR OP ÉEN DE NOR M ALIS AT IONEUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36 B-1050 Brussels
© 2002 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.
Ref. No. prEN 14487-1:2002 E
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
prEN 14487-1:2002 (E)
2
Contents
Foreword....................................................................................................................... ...............................................3
Introduction ................................................................................................................... ..............................................4
1 Scope ......................................................................................................................... .....................................4
2 Normative references .......................................................................................................... ..........................5
3 Terms and definitions......................................................................................................... ...........................63.1 Mix Component ............................................................................................................... ...............................63.2 Product..................................................................................................................... .......................................63.3 Process ..................................................................................................................... ......................................73.4 Properties .................................................................................................................. .....................................73.5 Execution ................................................................................................................... .....................................83.6 Operative................................................................................................................... ......................................83.7 Test/Inspection............................................................................................................. ..................................8
4 Classification and designation ................................................................................................ .....................94.1 Consistence of wet mix ...................................................................................................... ...........................94.2 Exposure classes............................................................................................................ ...............................94.3 Young sprayed concrete ...................................................................................................... .........................94.4 Compressive strength ........................................................................................................ .........................104.5 Flexural strength........................................................................................................... ...............................104.6 Fibre reinforced sprayed concrete........................................................................................... ..................10
5 Requirements for sprayed concrete ............................................................................................. .............115.1 Requirements for constituent materials...................................................................................... ..............115.2 Requirements for sprayed concrete composition............................................................................... .....125.3 Requirements on the basic mix............................................................................................... ...................145.4 Requirements on the fresh sprayed concrete .................................................................................. ........145.5 Requirements on hardened sprayed concrete ................................................................................... ......14
6 Specification of sprayed concrete ............................................................................................. ................166.1 General..................................................................................................................... .....................................166.2 Data for specifying designed mixes .......................................................................................... ................166.3 Data for specifying prescribed mix.......................................................................................... ..................17
7 Assessment of conformtity..................................................................................................... ....................177.1 General..................................................................................................................... .....................................177.2 Inspection classification ................................................................................................... ..........................177.3 Preconstruction testing..................................................................................................... ..........................187.4 Production control .......................................................................................................... .............................207.5 Conformity criteria......................................................................................................... ..............................24
Annex A (informative) Guidelines for Definitions, Specification and Conformity for Sprayed concrete.........26
Annex B (informative) General Guidelines for Steel Fibres for Sprayed Concrete ............................................34
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
prEN 14487-1:2002 (E)
3
Foreword
This document (prEN 14487-1) has been prepared by Technical Committee CEN/TC 104, "Concrete and relatedproducts", the secretariat of which is held by DIN.
This document is currently submitted to the CEN Enquiry.
This standard has taken EN 206 as a basis, some clauses where re-stated because of their importance and somewhere modified to meet the specific requirements of sprayed concrete.
This standard is only operable with product standards for constituent materials (ie. cement, aggregates, additions,admixtures and mixing water) and related test methods for sprayed concrete. These product standards and testmethod standards are under preparation by CEN but they will not be all available as European standards at thedate of publication of this standard. For this reason, the latest date of withdrawal of national standards (dow)conflicting with this standard will be the date when all standards listed below, together with the related standards fortest methods are available and implemented as European standards or ISO standards when appropriate or havethe status required by this standard.
EN 197-1, Cement — Composition, specifications and conformity criteria — Part 1: Comment cements.
EN 12620, Aggregates for concrete including those for use in roads and pavements.
EN 1008, Mixing water for concrete — Specifications and tests.
EN 934-2, Admixtures for concrete, mortar and grout — Part 2: Concrete admixtures - Definitions andrequirements.
EN 934-5, Admixtures for concrete, mortar and grout — Part 5: Admixtures for sprayed concrete.
EN 934-6, Admixtures for concrete, mortar and grout — Part 6: Sampling, conformity control and evaluation ofconformity
EN 450, Fly ash for concrete — Definitions, requirements and quality control.
EN 13263, Silica fume for concrete — Definitions, requirements and quality control.
EN 14487-2, Sprayed concrete — Part 2: Execution of Sprayed Concrete works.
EN 14488 Series, Sprayed concrete — Test Methods.
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
prEN 14487-1:2002 (E)
4
Introduction
This standard will be applied in Europe under different climatic and geographical conditions, different levels ofprotection and under different, well established, regional traditions and experience. Classes for concrete propertieshave been introduced to cover this situation. Where such general solutions were not possible, the relevant clausescontain permission for the application of EN 206 or other standards valid in place.
This standard incorporates rules for the use of constituent materials that are covered by European standards. Otherby-products of industrial processes, recycled materials etc. are in current use based on local experience. UntilEuropean specifications for these materials are available, this standard will not be provide rules for their use, butinstead refers to the recommendations given in EN 206 to apply national standards or provisions valid in the placeof use of the concrete.
This standard defines tasks for the specifier, producer and user. For example, the specifier is responsible for thespecification of concrete, clause 5 and 6 and the producer is responsible for conformity and production control,clause 7. The user is responsible for placing the concrete in the structure. In practice there may be serveraldifferent parties specifying requirements at various stages of the design and construction process eg. the client, thedesigner, the contractor, the concreting sub-contractor. Each is responsible for passing the specified requirements,together with any additional requirements, to the next party in the chain until they reach the producer. In the termsof this standard, this final compilation is known as the "specification".
Annex B gives guidelines for steel fibres for sprayed concrete. These guidelines remain valid until superseded by anew EN standard on fibres for concrete.
Further explanations and guidance on the application of this standard are given in Annex A.
1 Scope
This European Standard is applicable to sprayed concrete, to be used for repair and upgrading of structures, fornew structures and for strengthening of ground.
This standard covers :
Classification related to consistence of wet mix;
Environmental exposure classes; young, hardened and fibre reinforced concrete;
Requirements for constituent materials; concrete composition and for basic mix; and for fresh and hardenedconcrete and all types of fibre reinforced sprayed concrete.
Specification for designed and prescribed mixes
Conformity
The standard is applicable to wet mix as well as dry mix sprayed concrete.
The substrates to which sprayed concrete can be applied include:
ground (rock and soil)
sprayed concrete
different types of formwork
structural components constituted of concrete, masonry and steel
drainage materials
insulating materials
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
prEN 14487-1:2002 (E)
5
Additional or different requirements may be needed for applications not within this standard, for instance-refractory.
2 Normative references
This European Standard incorporates by dated or undated reference, provisions from other publications. Thesenormative references are cited at the appropriate places in the text and the publications are listed hereafter. Fordated references, subsequent amendments to or revisions of any of these publications apply to this EuropeanStandard only when incorporated in it by amendment or revision. For undated references the latest edition of thepublication referred to applies.
prEN 14487-1, Sprayed Concrete — Part 1: Definition, Specification and Conformity.
prEN 14487-2, Sprayed Concrete — Part 2: Execution for Structures, Ground Strengthening, Repair andUpgrading.
prEN 14488-1, Sprayed Concrete — Test Methods — Part 1: Sampling.
prEN 14488-2, Sprayed Concrete — Test Methods — Part 2: Determination of compressive strength of youngsprayed concrete.
prEN 14488-3, Sprayed Concrete — Test Methods — Part 3: Determination of flexural and residual strengths offibre reinforcement sprayed concrete.
prEN 14488-4, Sprayed Concrete — Test Methods — Part 4: Determination of bond strength.
prEN 14488-7, Sprayed Concrete — Test Methods — Part 7: Determination of fibre content.
EN 197-1, Cement — Composition, specification and conformity criteria — Part 1: Common cements.
EN 206-1:2000-12, Concrete — Part 1: Specification, performance, production and conformity.
EN 934-2, Admixtures for concrete, mortar and grout — Part 2: Concrete admixtures - Definitions andrequirements.
EN 934-5, Admixtures for concrete, mortar and grout — Part 5: Admixtures for sprayed concrete.
EN 934-6, Admixtures for concrete, mortar and grout — Part 6: Sampling, conformity control and evaluation ofconformity
prEN 1008:1997-05, Mixing water for concrete — Specification and tests.
prEN 1504-3:2001-03, Products and systems for protection and repair of concrete structures — Definitions,requirements, quality control and evaluation of conformity — Part 3: Structural and non structural repair.
EN 1542, Products and systems for the protection and repair of concrete structures – Test methods –Measurement of bond strength by pull-off
EN 12350-2, Testing fresh concrete — Part 2: Slump test.
EN 12350-5, Testing fresh concrete — Part 5: Flow table test.
EN 12350-6, Testing fresh concrete — Part 6: Density of fresh concrete.
EN 12390-5, Testing hardened concrete — Part 5: Determination of flexural strength.
EN 12390-7, Testing hardened concrete — Part 7: Density of hardened concrete.
EN 12390-8, Testing hardened concrete — Part 8: Depth of penetration of water under pressure.
EN 12504-1, Testing concrete in structures — Part 1: Cored specimens, taking, examining and testing incompression.
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
prEN 14487-1:2002 (E)
6
prEN 12504-3:1999-12, Testing concrete in structures — Part 3: Determination of pull-out force
prEN 12620:2000-03, Aggregates for concrete.
prEN 13412:1998-11, Products and systems for the protection and repair of concrete structures — Test Methods — Determination of elastic modulus in compression.
ENV 13670-1, Execution of concrete structures - Part 1: Common rules.
ISO 758, Liquid chemical products for industrial use — Determination of density at 20 °C.
EN ISO 7031, Resistance to water penetration.
ISO 6784, Modulus of elasticity in compression.
ISO 4012:1978, Concrete; Determination of compressive strength of test specimens.
3 Terms and definitions
For the purposes of this European Standard, the following terms and definitions apply.
3.1 Mix Component
3.1.1Fibresare short, discrete lengths of steel, organic polymer, glass or carbon and sufficiently small to be dispersed in thesprayed concrete.
3.2 Product
3.2.1Basic mixa concrete mix delivered ready-mixed or mixed on site intended to be fed into the spraying machine andtransported to the nozzle.
3.2.2Dry mixa basic mix with a maximum moisture content not exceeding 0,5 % to be used for the dry process.
3.2.3Factory blended dry mixa manufactured dry mix delivered to site in bags or silos.
3.2.4Fibre reinforced sprayed concretea sprayed concrete, including reinforcing fibres to improve certain properties of concrete.
3.2.5Reboundthe part of material that, having been sprayed through the nozzle, does not adhere to the surface of application.
3.2.6Reference sprayed concretesprayed concrete using site materials without accelerator for determining the changes in the mechanical properties(e.g strength loss).
3.2.7Sprayed concretea basic mix projected pneumatically from a nozzle into place, to produce a dense homogenous mass compacted byits own momentum.
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
prEN 14487-1:2002 (E)
7
3.2.8Wet mixa basic mix to be used in the wet process.
3.2.9Young sprayed concretesprayed concrete up to an age of 24 hours.
3.3 Process
3.3.1Curingmeasures to reduce harmful evaporation from concrete.
3.3.2Dense flow conveyingthe pump conveying of a wet mix to the nozzle, where it is pneumatically projected and compacted by adding high-pressure air. Dense flow conveying can only be used in the wet process.
3.3.3Dry processmethod of spraying a dry mix. (The necessary amount of additional water is added in the nozzle.)
3.3.4Nozzlegeneral term for the end of the conveying line, through which the mix is discharged. It consists of a mixing unit, intowhich – depending on the process – water, compressed air and/or admixtures are injected into the flow of the basicmix.
3.3.5Thin flow conveyingconveying of the basic mix through hoses or pipes in a continuous stream of high pressure air to the nozzle, wherethe force of the transportation is used to project and compact the mix.
3.3.6Wet processmethod of spraying a wet mix with an established water/cement ratio.
3.4 Properties
3.4.1Early development classesdefine the ranges of the early setting and early strength development upto 24 hours.
3.4.2Aspect ratio of fibreratio of length to diameter or equivalent diameter of the fibre.
3.4.3Deformation leveldegree of deformation that the lining undergoes after spraying.
3.4.4Equivalent diameter of fibrediameter of a circle with area equal to the cross-sectional area of a non-circular fibre.
3.4.5First peak flexural strengththe stress at the determined first peak load which fibre reinforced concrete withstands when subjected to a flexuraltest as specified in prEN 14488-3.
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
prEN 14487-1:2002 (E)
8
3.4.6Ultimate flexural strengththe stress corresponding to the maximum load which unreinforced or fibre reinforced concrete can withstand whensubjected to a flexural test as specified in EN 12390-5 and prEN 14488-3.
3.4.7Fresh sprayed concreteconcrete prior to setting.
3.4.8Residual strengthis the calculated stress in fibre reinforced concrete corresponding to a load in the load-deflection curve recordedduring the flexural test as defined in test prEN 14488-3.
3.4.9Shadow effectthe phenomena of a poorer concrete compaction or voidage on the rear side, of for example, a reinforcement bar,which is being sprayed on from one side only.
3.4.10Open timethe time between mixing and latest possible spraying of the basic mix. It depends on type and quantity of cement,moisture content for the dry mix and temperature.
3.5 Execution
3.5.1Repairthe replacement of inferior or deteriorated parts of concrete or masonry members.
3.5.2Substratethe surface to which the sprayed concrete is applied.
3.5.3Surface improvementthe use of layer of sprayed concrete in order to improve the durability or the appearance of the structure.
3.5.4Upgradingthe placing of additional sprayed concrete – with or without reinforcement – in order to increase the loadbearingcapacity or the integrity of the structure.
3.6 Operative
3.6.1Nozzlemanthe operator who controls and regulates the application of the sprayed concrete.
3.7 Test/Inspection
3.7.1Preliminary test for sprayed concretetest or tests to check how a sprayed concrete shall be composed in order to meet all the specified requirements inthe fresh and hardened state.
3.7.2Preconstruction testtest or tests performed with the proposed personnel, materials, equipment and spray method which the contractorwill carry out before the start of the spraying work to ensure the specified properties are met.
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
prEN 14487-1:2002 (E)
9
3.7.3Inspectionactivities carried out in order to check that execution is in accordance with the project specification.
3.7.4Inspection classdefines the subjects to be inspected and the extent of inspection, with reference to three inspection classes.
3.7.5Assessment of conformitysystematic examination of the extent to which a production process and a product are capable of fulfilling specialrequirements.
4 Classification and designation
4.1 Consistence of wet mix
The classification of consistence of fresh concrete in this standard is applicable for wet mixed concrete beforebeing sprayed and consistence classes in EN 206-1 shall be applied.
4.2 Exposure classes
The limiting values for composition of concrete related to the exposure classes given in EN 206-1, apply forsprayed concrete with the following exceptions:
Recommendation on minimum cement content does not apply to sprayed concrete
Recommendation on minimum air content is not applicable.
4.3 Young sprayed concrete
The young sprayed concrete shall be classified within the ranges of its significant early strength development. Therecommended classification is based on the average range of the typical setting rate according to the chosenproduction process and requirements.
When specified the strength development of the young sprayed concrete shall apply to the early strengthclasses J1, J2 or J3 according to figure 1. Early strength class J1 is defined in the field between the lines A and B,class J2 in the field between the lines B and C and class J3 above the line C.
Early strength development shall be determined with penetration needle method according to test standardprEN 14488-2 and bolt driving method according to test standard prEN 14488-2.
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
prEN 14487-1:2002 (E)
10
Figure 1 — Early strength classes of young sprayed concrete
NOTE Early compressive strength of young concrete up to 24 hours can be estimated by different indirect test methods inaccordance with Table 1:
Table 1 — Range of strength of young concrete determined by different test methods
Method Range of strength of youngconcrete (MPa)
prEN 14488-2 – MethodA
0,2–1,2
prEN 14488-2 – MethodB
3–16
prEN 12504-3:1999-12 > 10
4.4 Compressive strength
The compressive strength of sprayed concrete is classified according to EN 206-1.
4.5 Flexural strength
Shall be tested according to EN 12390-5 or prEN 14488-3 whichever is appropriate for comparative purposes.
4.6 Fibre reinforced sprayed concrete
Fibre reinforced sprayed concrete has additional and/or complementary properties, some of which are related toresidual strength and energy absorption capacity. Informative guidance to the classification prinicples are given inAppendix B. Informative guidance to the classification principles are given in Appendix B
4.6.1 Residual strength classes
Classification of residual strength is made by specification of a strength level at a certain deformation rangeaccording to Table 2 and determined in accordance with prEN 14488-3 and denoted by combination of the signsfor the specified deformation range and strength level. e.g. Residual strength Class D2S2 means that the strengthmust exceed 2 Mpa at 0,5, 1 and 2 mm deflection.
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
prEN 14487-1:2002 (E)
11
Table 2 — Definitions of residual strength classes
Deformation range Strength level (Minimum strength, MPa)
Deflection
mmS1 S2 S3 S4
D1 0,5–1
D2 0,5–2
D3 0,5–4
1 2 3 4
5 Requirements for sprayed concrete
5.1 Requirements for constituent materials
5.1.1 Suitability for constituent materials
Constituent materials shall not contain harmful ingredients in such quantities as may be detrimental to the durabilityof the concrete, or cause corrosion of the reinforcement. Only constituent materials with established suitability shallbe used.
Suitability of a constituent material is established when it conforms to a European Standard.
Alternatively, where either the European Standard does not cover the particular material or its intendedperformance, or the material deviates from the requirements of an existing European Standard, the establishmentof suitability may result from:
a European Technical Approval which refers specifically to the use of the material in sprayed concreteconforming to this standard.
from the relevant national standards or provisions valid in the place of use of the sprayed concrete, whichrefers specifically to the use of the material in sprayed concrete conforming to this standard.
5.1.2 Constituent materials
Requirements for constituent materials are given in table 4.
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
prEN 14487-1:2002 (E)
12
Table 3 — Requirements for constituent materials
Constituent material Requirements
Cement The suitability is established for cement conforming to EN 197-1
Aggregates The suitability is established for aggregate conforming to prEN 12620:2000-03.
Mixing water Mixing water shall conform to prEN 1008:1997-05.
Admixtures Admixtures shall conform to EN 934-2 and/or prEN 934-5:1998-11 andEN 934-6
Additions (including mineralfillers and pigments)
Additions shall comply to requirements as specified in EN 206-1
Polymers modified sprayedconcrete
Polymer modified sprayed concrete used for repair shall comply withprEN 1504-3.
Fibres Steel fibres for reinforcement shall meet the requirements of Annex A(Normative).
Other fibres shall conform to general clause 5.1.
5.2 Requirements for sprayed concrete composition
5.2.1 General
The concrete mix proportions shall be selected to satisfy all the performance criteria for fresh and hardenedconcrete including consistence (wet mix), density, strength, durability, protection of embedded steel againstcorrosion and taking into account the current process technique and quantity of rebound and dust when executingthe spraying works.
The requirements for concrete composition and properties related to exposure classes depend on the intendeddesign life of the sprayed concrete structure and in conformity with EN 206-1.
Values for the composition of the concrete refer to the concrete after spraying and have to take into account theinfluence of water addition by the spraying process as well as the effect of rebound.
The achievement of the design life depends on:
the concrete being sprayed and cured in accordance with ENV 13670-1.
the sprayed concrete having an adequate cover to reinforcement or required extra thickness, in case of steelfibre reinforcement, the cover requirement does not apply.
the sprayed concrete being used in the environment for which the particular limiting values apply;
the anticipated maintenance without major repair.
5.2.2 Concrete composition
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
prEN 14487-1:2002 (E)
13
Table 4 — Requirement on concrete composition
Component Requirement and Test Methods
Use of cement The type of cement shall be specified, taking into account the influence of current temperature andheat evaluation on required workability time, the requirement on strength development and finalstrength as well as the current curing conditions. If required, it must be checked by means of anappropriate method.
For permanent structures, the environmental conditions to which the sprayed concrete is exposedmust be regarded according to EN 206-1:2000-12 clause 5.3.1.as well as precautions regardingresistance to alkali-silica reactions according to EN 206-1:2000-12 clause 5.2.3.4
Use of aggregates Precautions regarding resistance to alkali-silica reactions according to EN 206-1:2000-12clause 5.2.3.4 shall be applied.
Use of admixtures Limitations for the use of admixtures set out in EN 934-2 and prEN 934- 5:1998-11 shall not beexceeded.
Use of additions The use of additions for permanent structures shall conform to clause EN 206-1:2000-12 clause 5.2.5
Chloride content The chloride content of a sprayed concrete for permanent structure shall not exceed the values givenin EN 206-1:2000-12 Table 10. For steel fibre reinforced sprayed concrete, values for steelreinforcement apply.
Water/cement ratio For permanent structures, the environmental conditions to which the sprayed concrete is exposedmust be regarded according to EN 206-1:2000-12, clause 5.3
Where water/cement ratio of a wet mix is specified, it shall be calculated according to EN 206-1:2000-12, 5.4.2.
For fibre reinforced concrete
Use of fibres The use of steel fibres shall comply to Annex A, other types of fibres shall comply to clause 5.1 of thisstandard. Fibres shall be added in such a way that a homogenous distribution is obtained.
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
prEN 14487-1:2002 (E)
14
5.3 Requirements on the basic mix
Table 5 — Requirements of the basic mix
Property Requirement and Test Methods
Consistence of basic mix The concrete consistency required for spraying depends on the type of conveyanceand the application procedure.
For sampling and determination of consistency of the basic wet mix sprayedconcrete, EN 206-1 applies.
Temperature The temperature of the basic mix before applying shall be between 5 °C and 30 °Cin order to maintain the workability conditions and avoid adverse set effects.
5.4 Requirements on the fresh sprayed concrete
Table 6 — Requirements of the fresh concrete
Property Requirement and Test Methods
Density If specified, the density shall be determined in accordance with EN 12350-6
Fore fibre reinforced sprayed concrete
5.5 Requirements on hardened sprayed concrete
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
prEN 14487-1:2002 (E)
15
Table 7 — Requirements of hardened concrete
Property Requirement and Test Methods
Young sprayed concrete If specified an estimate of the early compressive strength can be determined inaccordance with prEN 14488-2, alternatively the early strength can be determinedfrom a pull-out test in accordance with prEN 12504-3:1999-12 for non fibrereinforced concrete.
Compressive strength The compressive strength of sprayed concrete is expressed and defined accordingto EN 206-1. The strength shall be determined from tests carried out at 28 days inaccordance with ISO 4012:1978 on drilled cores, taken from the sprayed concretestructure according to EN 12504-1, or from sprayed panels according toprEN 14488-1. Their minimum diameter shall be 50 mm and the height/diameterratio shall be either 1.0 or 2.0, specimen shall be tested in accordance withEN 12504-1.
NOTE length/diameter ratio:
– 2.0 if the strength result is to be compared to cylinder strength
– 1.0 if the strength result is to be compared to cube strength.
Density If specified, the density of hardened concrete shall be determined in accordance withEN 12390-7.
Modulus of elasticity If specified, the modulus of elasticity in compression shall be determined inaccordance with ISO 6784, except in repair application where prEN 13412:1998-11.Shall apply.
Flexural strength If specified, the flexural strength shall be determined in accordance withprEN 12390-5 for plain sprayed concrete unless it is to be compared to fibrereinforced sprayed concrete when prEN 14488-Part 3 shall be used.
Resistance to waterpenetration
If water resistant sprayed concrete is specified, the resistance to water penetrationshall be determined in accordance with EN 12390-8. The depth of an insitu samplemay be reduced where the layer thickness is less than 150 mm. The depth shall besufficient to ensure that complete penetration does not occur. In addition thedirection of water penetration and the method of surface preparation shall bespecified. The maximum value of penetration shall be 50 mm.
The test is normally performed at 28 days.
Frost resistance If specified, the frost resistance of sprayed concrete subjected to freezing andthawing shall be determined in accordance with prEN 14488-8
Bond strength tosubstrate
If specified, the bond strength shall be determined for repair materials in accordancewith EN 1542 with the exception of mould size which shall not be smaller than500 mm × 500 mm to provide a border of at least 100 mm in order to excludedefective material in the edges of the specimens. Surface finish shall either betrowelled when wet or ground when hardened otherwise it shall be on drilled cores inaccordance with prEN 14488-4.
For fibre reinforced sprayed concrete
First peak flexuralstrength
If the first peak flexural strength of fibre reinforced concrete is specified, the firstpeak strength shall be expressed as the average value of the strength at themoment of first peak determined on three samples in accordance with prEN 14488-3. The test shall normally be performed at 28 days.
Ultimate flexural strength If specified, the flexural strength of sprayed concrete shall be expressed as ffl whendetermined according to prEN 14488-3. Unless otherwise required tests shallnormally be performed at 28 days
Residual strength If the residual strength class of fibre reinforced concrete is specified, it shall be donefor a specified deformation level. The stress-deflection curve shall be determined onthree samples in accordance with prEN 14488-3. The test is normally done at28 days.
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
prEN 14487-1:2002 (E)
16
6 Specification of sprayed concrete
6.1 General
Sprayed concrete shall be specified either as a designed mix referring to classification given in clause 4 andrequirements given in clause 5, or as prescribed mix by prescribing the composition on the basis of results of initialtests or information obtained from long term experiences with comparable sprayed concrete. Where inspectionclasses 2 and 3 are specified only designed mixes shall be used. Where class 1 applies, prescribed mix may beused.
Basic data for sprayed concrete shall be indicated in all cases and additional data shall be indicated when required.
6.2 Data for specifying designed mixes
6.2.1 Basic data
Compressive strength class
Exposure class
Maximum chloride content
In the case of fibre reinforced concrete
residual strength
6.2.2 Additional data
The concrete specifications may also contain additional requirements such as:
minimum cement content related to exposure class
special requirements for cement properties (e.g. sulphate resistant cement)
maximum water/cement ratio related to exposure classes
early strength development
maximum strength
resistance to water penetration
water absorption
bond to substrate
frost resistance
modulus of elasticity
In the case of fibre reinforced concrete
first peak flexural strength
ultimate flexural strength
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
prEN 14487-1:2002 (E)
17
6.3 Data for specifying prescribed mix
6.3.1 Basic data
The prescribed mix shall be specified by the following basic data:
cement type and content
strength class
water/cement ratio
type of aggregate and limitations for grading
type and quantity of admixtures
type and quantities of additions
sources of all concrete constituents when admixture or additions are used
In the case of fibre reinforced concrete
fibre type and content
6.3.2 Additional Data
additional requirements for aggregate
special requirements regarding the temperature of the basic mix for wet mix sprayed
concrete or dry mix sprayed concrete.
7 Assessment of conformtity
7.1 General
Conformity control comprises the combination of actions and decisions to be taken in accordance with conformityrules adopted in advance to check the conformity of the sprayed concrete with the specifications.
Conformity shall be assessed by preconstruction control as well as test during execution and be applied inaccordance with the applicable inspection classification. Production control includes process control and control ofsprayed concrete
The conformity or non-conformity is judged against the conformity criteria and is valid for preconstruction tests aswell as for production tests. Conformity leads to acceptance while non-conformity shall lead to corrective action.
NOTE If the results of conformity tests do not fulfil requirements, supplementary testing according to EN 12504-1 on corestaken from the structure may be required or a combination of tests on cores and non-destructive tests on the structure e gaccording to EN 12504-2.
7.2 Inspection classification
For conformity control of sprayed concrete the following inspection classes have been established.
Inspection class 1
Inspection class 2
Inspection class 3
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
prEN 14487-1:2002 (E)
18
The choice of class shall be based on the characteristics of the project including degree of risk and required designlife. The informative Annex A gives guidance for selection of inspection classes.
7.3 Preconstruction testing
Preconstruction test shall be performed according to Table 8 unless otherwise specified in production controlsystem (Producer's production control manual).
It shall be demonstrated that the requirements can be met before start of execution.
The preconstruction tests shall be performed with the same personnel, materials, equipment and spray methodwhich will be used during production.
For prescribed sprayed concrete only test of compressive strength is applicable.
When long term experience with similar sprayed concrete equipment and same personnel is availablepreconstruction testing is not necessary. The concrete design and design relationships shall be re-establishedwhen there is a significant change in constituent materials, composition, personal or equipment as indicated below:
changes to higher water/cement ratio
change of aggregate type or supplier
change of max aggregate size
change of admixtures or additives
change of cement supplier
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
prEN 14487-1:2002 (E)
19
Table 8 — Preconstruction tests — requirement for the designed sprayed concrete
All parameters specified and marked by shadow files in the table, shall be tested
Mandatory Mandatory if specified
Type of work : Repair and upgrading New structures Strengthening of ground
Inspection Class: 1 2 3 1 2 3 1 2 3
Property test
Test sprayinga
Compressive strength
Early strength development
Frost resistance
Water penetration
Bond
Modulus of Elasticity
Additional for fibre reinforced sprayed concrete
First peak flexural strength
Ultimate flexural strength
Residual strengtha
Energy absorption capacityb
Fibre content
a Amount to be specified to each specific project.
b Either residual strength or Energy Absorption Capacity can be specified.
Licensed Copy: University of Bath Library, University of Bath, 09 October 2003, Uncontrolled Copy, (c) BSI
prEN 14487-1:2002 (E)
20
7.4 Production control
7.4.1 General
Production control comprises all measures necessary to maintain and regulate the quality of the sprayed concretein conformity with specified requirements.
Production control shall be related to the characteristics of the project including the degree of risk and expecteddesign life.
Production control consist of following parts
constituent materials control (table 9)
control of basic mix (table 10)
sprayed concrete properties (table 11)
NOTE Inspection of execution is covered in EN 14487 Part-2.
All relevant data from the process shall be recorded.
7.4.2 Constituent materials control
The control of constituent material shall be performed according to table 9.
Table 9 — Constituent materials control
Min sampling frequencyMaterial Inspection/test Purpose
Class 1 Class 2 Class 3
1 Cements Inspection of deliveryticket
To ascertain correcttype and source
Each delivery
2 Aggregates Inspection of deliveryticketa
To ascertain correcttype and source
Each delivery
3 Test by sieve analysisaccording to prEN 933-1or aggregate supplierinformation
To assess compliancewith standard or otheragreed grading
first delivery from newsource
4 Test for impurities oraggregate supplierinformation
To asses thepresence and quantityof impurities
first delivery from newsource
5 Additionalcontrol forlight weightconcrete
Test according toISO 6782
To measure the bulkdensity
first delivery from newsource
Relevant materials control must, in case of doubts, be performed independent of inspection class.
6 Admixtures Inspection of deliveryticket and label oncontainer according toEN 934-6.
To ascertain if theconsignment is asordered and properlymarked
Each delivery
7 Inspection of theadmixture
For comparison withmanufacturer’s statedvalue
Each delivery
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
prEN 14487-1:2002 (E)
21
Table 9 (continued)
Min sampling frequencyMaterial Inspection/test Purpose
Class 1 Class 2 Class 3
8 Test for densityaccording to ISO 758
For comparison withmanufacturer’s statedvalue
In case of doubt
9 Additions
bulk powder
Inspection of deliveryticket
To ascertain if theconsignment is asordered and from thecorrect source
Each delivery
10 Additions insuspension
Inspection of deliveryticket
To ascertain if theconsignment is asordered and from thecorrect source
Each delivery
11 Test for densityaccording to ISO 758
To ascertainuniformity
Each delivery
12 Water Test according toprEN 1008:1997-05
To ascertain that thewater is free fromharmful constituents
If the water is not potable;when new source is usedfor first time; and in case ofdoubt
13 Fibres Inspection of length,diameter and shape
To ascertain if theconsignment is asordered and from thecorrect source
Each delivery
a According to EN 206-1. (At the delivery at least the origin type and strength class are to be given on the delivery ticket)
7.4.3 Control of basic mix
The control of the basic mix shall be performed according to table 10.
Table 10 — Control of basic mix
Min sampling frequencyType of test Inspection/test Purpose
Class 1 Class 2 Class 3
1 Consistence whenusing wet-mixmethod
Test according toEN 12350-2 orEN 12350-5
To assess conformitywith required class ofconsistence and tocheck possiblechanges of watercontent
at start of production
2 Admixture contentexcept accelerator
Record of thequantity added
To check the content Optional Every batch
3 Additions content Record of thequantity added
To check the content Optional Every batch
4 Fibre content According toprEN 14488-7
Every batch
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
prEN 14487-1:2002 (E)
22
7.4.4 Control of sprayed concrete properties
If testing is required by the project specification, the sprayed concrete shall be tested according to Table 11.
The test frequencies refer to the normal continuous production situation. Four times higher test frequency shouldbe applied in the beginning of a continuous working period or during certain severe parts of a project. However,normally no more than two tests per working day should be necessary.
After four following acceptable results, normal frequency shall be applied.
The minimum rate of sampling and testing for production control of concrete shall be at the rate, which gives thehighest number of samples.
The minimum sampling frequencies are valid for production up to the given extension. That is, for minor project, atleast one test sample shall be made where applicable.
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
prEN 14487-1:2002 (E)
23
Table 11 — Control of sprayed concrete properties
Min sampling frequency Repair and waterproofing New structuresType of test
Inspection/ testaccording to Class 1 Class 2 Class 3 Class 1 Class 2 Class 3 Class 1 Class 2 Class 3
Control of fresh concrete
1 Water/cement ratio of freshconcrete when using wet mixmethod
By calculation or by testmethod
Daily Daily Daily
2 Accelerator By calculation fromrecord of quantity added
Daily Daily Daily
3 Fibre content in the freshconcrete
According toprEN 14488 7
1/200 mor1/1 000 m3
1/100 m3 or1/500 m3
1/1 000 m3 ormin 1 (IS)1
1/500 m3
min 2 IS)1/250 m3 ormin 3 (IS)
1/200 m3 or1/1 000 m3 ormin 1 (IS)
1/100 m3 or1/500 m3 ormin 2 (IS)
1/50 m3 or1/250 m3 ormin 3 (IS)
Control of hardened concrete
4 Strength test of youngsprayed concrete
prEN 14488-2 1/5 000 m2 or1/2 months
½ 500 m2 or1/month
1/250 m2 or2/month
1/5 000 m2
min 1 (IS)1/2 000 m2
min 2 (IS)1/1 000 m2
min 3 (IS)1/5 000 m2
min 1 (IS)1/2 000 m2
min 2 (IS)1/1 000 m2
min 3 (IS)
5 Compressive strength EN ISO 4012 1/1 000 m3 or1/5 000 m2
1/200 m3 or1/500 m2
1/100 m3 or1/500 m2
1/500 m3 or1/2 500 m2 ormin 1 (IS)
1/100 m3 or1/500 m2 ormin 2 (IS)
1/50 m3 or1/250 m2ormin3 (IS)
1/500 m3 or1/2 500 m2 ormin 1 (IS)
1/100 m3 or1/500 m2 ormin 2 (IS)
1/50 m3 or1/250 m2 ormin 3 (IS)
6 Density of hardened concrete prEN 14488-8 When testing compressive strength When testing compressive strength When testing compressive strength
7 Resistance to waterpenetration
EN ISO 7031 As specified inthe productspecification
As specified inthe productspecification
1/100 m2 ormin 1 (IS)
1/500 m2 ormin 2 (IS)
1/250 m2 ormin 3 (IS)
1/1 000 m2 ormin 1 (IS)
1/500 m2 ormin 2 (IS)
1/250 m2 ormin 3 (IS)
8 Frost resistance prEN 14488-8 As specified inthe productspecification
As specified inthe productspecification
1/1 000 m2 ormin 1 (IS)
1/500 m2 ormin 2 (IS)
1/250 m2 ormin 3 (IS)
1/1 000 m2 ormin 1 (IS)
1/500 m2 ormin 2 (IS)
1/250 m2 ormin 3 (IS)
9 Bond strength prEN 14488-4 1/200 m or1/1 000 m2
1/100 m3 or1/500 m2
1/1 000 m2 ormin 1 (IS)
1/500 m2 ormin 2 (IS)
1/250 m2 ormin 3 (IS)
1/1 000 m2 ormin 1 (IS)
1/500 m2 ormin 2 (IS)
1/250 m2 ormin 3 (IS)
Modulus of Elasticity / prEN 13412 or ISO 6784
Control of fibre reinforced sprayed concrete
10 Fibre content In hardened concreteaccording to prEN 14488-7
When testing residual strength When testing residual strength When testing residual strength
11 Residual strength prEN 14488-3 1/2 000 m3 or1/10 000 m2
1/400 m3 or1/2 000 m2
1/100 m3 or1/500 m2
Min 1 (IS) 1/2 000 m2 ormin 2 (IS)
1/500 m2 ormin 3 (IS)
1/2 000 m2 ormin 2 (IS)
1/500 m2 ormin 3 (IS)
12 Ultimate flexural strength prEN 14488-3 When testing residual strength When testing residual strength When testing residual strength
13 First peak flexural strength prEN 14488-3 When testing residual strength When testing residual strength When testing residual strength
Licensed Copy: University of Bath Library, University of Bath, 09 October 2003, Uncontrolled Copy, (c) BSI
prEN 14487-1:2002 (E)
24
7.5 Conformity criteria
7.5.1 General
7.5.1.1 Early strength development
Conformity of sprayed concrete early strength development tested with penetration needle method according totest standard prEN 14488-2 is obtained if the compressive strength fc [MPa] calculated with the mean of at least10 samples of measured penetration force F [N] within a certain time period of measurement does not exceed thespecified field of early strength development (table 12).
Table 12 — Conformity criteria for penetration needle method (test standard prEN 14488-2)
Test range up to 1,2 [MPa]
Maximum grain size 8, 11 [mm] 16 [mm]
Number of results F [N] Not less than 10
Compressive strength fc [MPa] fc = 0,0015 F + 0,0182 fc = 0,0018 F – 0,0273
Conformity of sprayed concrete early strength development tested with bolt driving method according to teststandard prEN 14488-2 is obtained if the compressive strength fc [MPa] calculated with the mean of at least10 samples of measured penetration depth L [mm] or the ratio F/L – pull-out force F [MPa] to penetration depthL [mm] – within a certain time period of measurement does not exceed the specified field of early strengthdevelopment (table 13).
Table 13 — Conformity criteria for bolt driving method (test standard prEN 14488-2)
Test range 3 to 16 [MPa]
Maximum grain size 8, 11 [mm]
Measured resultspenetration depth L [mm]
pull-out force F [MPa]
Calculated mean value ratio F/L [N/mm]
Number of results not less than 10
Compressive strength fc [MPa] fc = 0,13 F/L + 0,3511
7.5.1.2 Compressive strength
Conformity of sprayed concrete compressive strength is assessed according to table 14 for:
groups of "n" consecutive test results xn (criterion 1);
each individual test result xi (criterion 2).
Table 14 — Conformity criteria for compressive strength test results from the structure or from test panels
Criterion 1 Criterion 2
Number “ n” of results in the group Mean of “n” results xn in MPa Any individual test results xi in MPa
not less than 15 ≥ fck + 1,48 δ ≥ 0,75 fck
6–14 ≥ fck + 1,65 δ ≥ 0,75 fck
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
prEN 14487-1:2002 (E)
25
Where:
fck is the characteristic compressive strength
d is the standard deviation from, at least 6 samples.
7.5.1.3 Resistance to water penetration
Conformity is obtained if every measured value is lower than the required value.
7.5.1.4 Frost resistance
Conformity is obtained if every measured value is lower than the required value.
7.5.1.5 Bond strength
Conformity of sprayed concrete bond strength is obtained if mean value of a set of samples (normally3 specimens), is not lower than the required value.
7.5.2 Additional for fibre reinforced sprayed concrete:
7.5.2.1 Fibre content
Conformity is obtained if the mean value of measured fibre content from a set of, at least 6 samples, is not lowerthan Vf – 4 kg/m3 where Vf is the target value for the fibre content specified according to preconstruction testing.
7.5.2.2 First peak flexural strength
Conformity of first peak strength is obtained when
the mean value from test on 3 test samples fulfils the requirement on the first peak strength
no individual test result deviates more than ± 25 % from the calculated mean value.
7.5.2.3 Ultimate flexural strength
Conformity of flexural strength is obtained when
the mean value from test on 3 test samples fulfils the requirement on the flexural strength
no individual test result deviates more than ± 25 % from the calculated mean value.
7.5.2.4 Residual strength
Conformity of residual strength is obtained when
At least two of three beams have a residual strength on, or above, the specified residual strength boundarygiven in Table 2 up to the deflection limit appropriate to the specified deformation level.
The third beam shall for the specified deformation level in no point have a residual stress that is lower than10 % of the stress corresponding to the boundary of the specified strength class.
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
prEN 14487-1:2002 (E)
26
Annex A(informative)
Guidelines for Definitions, Specification and Conformity for Sprayedconcrete
Foreword
This Annex provides guidance and background information on the Normative text. The contents of this Annex arenumbered in the same way as the Normative text to facilitate reference, where there is no information a specificclause, only the title of the clause stated.
A.1 Scope
The application of sprayed concrete covers the entire field of civil engineering and building construction. It isparticularly adapted for work under the following special condition:
no formwork
application in thin layers
early strength
special construction methods
A.2 Classification
A.2.1 Requirements related to exposure classes
The limiting values for composition of concrete related to the exposure classes given in EN 206-1:2000-12clause 5.3, apply for sprayed concrete with the following exceptions:
Recommendation on minimum cement content does not apply to sprayed concrete
Recommendation on minimum air content is not applicable.
A.2.2 Fibre reinforced sprayed concrete
The different ways of specifying the ductility of fibre reinforced sprayed concrete in terms of residual strength andenergy absorption capacity are not directly comparable.
The residual strength can be prescribed when the concrete characteristics are used in a structural design model.
The energy absorption value measured on a plate can be prescribed when in the case of rock-bolting emphasis islaid on energy which has to be absorbed during the deformation on the rock.
A.2.2.1 Residual Strength Classes
The specification regarding residual strength are related to the deformation conditions of the rock. A higherdeformation of the rock will demand higher deflection capabilities of the concrete lining.
The purpose of the deformation are to give flexibility to the designers in the choice of deformation required of thesprayed concrete under service conditions. For the purpose of design, the deflection limit for deformation level can
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
prEN 14487-1:2002 (E)
27
be considered in terms of the equivalent angular rotation for bean cracked at midspan (e.g. for a bean of450 mm × 125 mm × 75 mm test according to prEN 14488-3)
Three typical rock deformation ranges have been identified
D1 corresponding with an angular deformation = l/250
D2 corresponding with an angular deformation = l/125
D3 corresponding with an angular deformation = l/56
Correspondingly four residual strength levels, S1–S4, are defined which in combination with applicable deformationrange, can be specified in terms of residual strength class.
An illustrative example is given in figure A.1 for a typical fibre reinforced sprayed concrete bean, this bean fulfils therequirement for residual strength class D1S3 (as well as D2S2 and D2S1).
Figure A.1
A.3 Requirements for Sprayed Concrete
A.3.1 Constituent Materials
A.3.1.1 Cement
It is of particular importance for sprayed concrete to use cements of consistent properties, especially with respect toits chemical composition, fineness and setting behaviour.
If characteristic values as well as requirements to the homogeneity should be defined, the cement supplier and thecontractor should agree prior to the start of deliveries.
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
prEN 14487-1:2002 (E)
28
A.3.2 Requirements for the sprayed concrete composition
A.3.2.1 General
Determination of the basic-mix proportions should consider the fact that the quantity of rebound during applicationwill result in a different proportioning of the applied concrete. The composition, especially the content of the cementpaste and the water/cement ratio in the basic-mix should, therefore, be so designed that the sprayed concrete onsite has the quantity of cement necessary to obtain the required characteristics and strength. An excessive cementcontent, due to high rebound, can result in excessive shrinkage and a concrete stiffness that will be detrimental tothe interaction between old and new parts of the member.
A.3.2.2 Use of cement
The cement temperature should not exceed + 80 °C when the cement is delivered from the cement mill and+ 70 °C when it is filled into the silos of the mixing plant. A higher temperature of the cement delivered from thecement mill is only admissible if precautions to cool the cement before use are taken.
A.3.2.3 Use of aggregates
The use of a properly balanced sieve curve is necessary in order to have enough fine material to assure a goodpumpability of the basic mix (wet process) and a balanced amount of coarse aggregate to achieve the compaction,strength and permeability requirements desired, keeping at a minimum the cement/aggregate ratio (less shrinkage)and to help to reduce the rebound rate.
The use of large sized maximum aggregates (especially over 10 mm) may result in a higher rebound.
The excess of fines in the mix leads to a higher demand of water.
A.3.2.4 Use of admixtures
Sprayed Concrete Admixtures
Special attention should be given to the adaptation of the cement with regard to the acceleration of setting, earlystrength and decrease in final strength. Laboratory test methods should be applied for this purpose.
With liquid accelerators, special attention should be paid to the storage stability, the working temperature and thecompatibility to water added in accordance to the directions given from the producer.
A.3.2.5 Use of additions
Use of Fibres
Because of the possible increased proportion of fibres in the rebound, this needs to be taken into account whenchoosing the concrete composition.
It is common practice to use steel fibres up to 30 mm for the dry process and up to 40 mm for the wet process. Thelength of the fibres should not exceed 75 % of the internal diameter of the pipes or hoses used unless it has beenproven that longer fibres can be used without blockage. If the fibres are added in the form of endless wire directly atthe nozzle, even longer fibres may be used.
The values for a minimum overlap between fibres. s may be estimated as
3
f
f2f
4 ρπ ld
s××= (A.1)
where:
l f length of fibre
df equivalent diameter of fibre
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
prEN 14487-1:2002 (E)
29
ρf fibre percentage
s must be lower than 0,45 to ensure a minimum overlap.
Water/cement ratio
For dry mix sprayed concrete, the water/cement ratio should be controlled during spraying. In the case of correctlyapplied sprayed concrete, the water/cement ratio can be expected to be below 0,5.
Fines modulus
Due to the spraying process, the control of the water to cement ratio for the dry process is not practical under siteconditions for sprayed concrete. To ensure the required resistance against environmental conditions, the content ofwater and fines ie. fines modulus (cement and aggregates less than 0,25 mm in size) should be controlled atregular intervals during production. The maximum content of water and fines, depending on the exposure classes,should be fixed by the suitability test. This may not apply to accelerated sprayed concrete.
A.3.3 Requirements on hardened sprayed concrete
Frost resistance
Structures exposed to severe frost action should fulfil the requirements for frost resistant concrete.
The type of freeze-thaw test shall be specified in the project specification.
A.4 Specification of sprayed concrete
A.4.1 General
It is common practice to use the designed mix approach instead of the prescribed mix.
A.4.1.1 Basic data
It is difficult to control during application, the water content with the dry process. Usually in situ water/cement ratiosare in the range 0,35 to 0,50.
A.5 Assessment of conformity
A.5.1 Inspection classification
Examples of inspection classes are given in Tables A.1 and A.2.
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
prEN 14487-1:2002 (E)
30
Table A.1 — Examples related to strengthening of ground
Class Example of inspection classification
1 Mainly small permanent constructions with minor degree of risk in design and structural instability aswell as low durability requirements.
Temporary constructions with short design life and low risk of structural instability.
EXAMPLE
stabilisation’s for small or temporary slopes or building pits
temporary openings or mine openings
pilot tunnels
drifts and headings for large excavations
access tunnels or for temporary use
small storage rooms
2 Permanent constructions with normal design complexity regarding risk of structural instability orfunctional safety as well as constructions with moderate durability requirements/design life.
Temporary constructions with normal risk in structural instability and normal design life.
EXAMPLE
lining for double-shell constructions
single-shell constructions
storage rooms
low traffic tunnels
public facilities
access tunnels for permanent use
permanent stabilisation’s of slopes and excavation surfaces
exacting mine tunnels
temporary sprayed concrete for tunnels and caverns in poor ground
3 Permanent constructions with special design complexity regarding risk of structural instability orfunctional safety as well as constructions with high durability requirements/long design life.
Temporary constructions with special risk in structural instability and relatively long design life.
EXAMPLE
caverns in very poor ground
large public facilities
high traffic tunnels
defence shelters
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
prEN 14487-1:2002 (E)
31
Table A.2 — Examples related to new structures, repair and upgrading
Newstructure Repair and upgradingType of work
Kind and use of the structureClass Class
Sprayed concrete category a Structural Structural nonstructural
1
Rail or road tunnels with heavy traffic – under sea and river tunnels –sewers in high risk areas – large underground parking – viaducts onmajor roads – large darns – nuclear power stations – factoriesclassed as high risk – large shopping centres – tower blocks –hospitals – schools – exhibition halls, etc...
3 3 3
2
Rail or road tunnels, bridges, viaducts, etc with medium traffic flow –small shops – apartment blocks – small underground parking – smalldarns – canals – sewers in medium size urban areas – factoriesclassed as medium risk – power stations – aqueduct for drinkingwater
3 3 2
3Tunnels – bridges – viaducts and other structures with light trafficcirculation – sewers in small urban zones – small buildings – houses– low risk factories
3 2 1
4 Sewers in un-urbanised zones – aqueducts for industrial water –cable shafts in an environment without risk – no-risk factories
2 2 1
5 Supporting walls in a no-risk zone – open-top aqueduct or canal –surrounding wall
2 2 1
a Categories of sprayed concrete
Structural : Sprayed concrete for new structures and for the replacement of deteriorated parts having load-bearing functions.
Non structural : Sprayed concrete for the repair of deteriorated parts, having no load-bearing functions, but other functions such as increaseof durability or fire protection.
A.5.1.1 Conformity criteria of young sprayed concrete
The very early strength development in between the test range 0,1 to 1,2 [MPa] is measured with the penetrationneedle method (needle 3 [mm], taper angle 60°). The mean of the values of penetration force F [N] to a depth of15 mm measured with the penetration needle follow the formula for calculating the early compressive strengthfc [MPa] dependent on the specified or chosen maximum grain size:
[ ] 0182,00015,0MPa11,8c += Ff (A.2)
The early strength development in between the test range 1 to 8 [MPa] is measured with the bolt driving method(Hilti DX 450 L, white cartridge). The mean of the values of penetration depth L [mm] determined with the boltdriving method follow the formula for calculating the early compressive strength fc [MPa] dependent on the specifiedor chosen maximum grain size 8, 11 [mm] in the test range 1-8 [MPa] (figure A 2):
[ ] ( ) 0598,0L196,6511,8c MPa −= ef (A.3)
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
prEN 14487-1:2002 (E)
32
Figure A.2 — Calibration curve for bolt driving method (test range 1,0 – 8,0 [MPa])
The early strength development in between the test range 3 to 16 [MPa] is measured with the bolt driving method(Hilti DX 450 L, green cartridge). The mean of the calculated values of the ratio F/L [N/mm] (ratio of measuredpenetration force F [MPa] to measured penetration depth L [mm]) determined with the bolt driving method followthe formula for calculating the early compressive strength fc [MPa] dependent on the specified or chosen maximumgrain size 8, 11 [mm] in the test range 3-16 [MPa] (figure A.3):
[ ] 3511,0/13,0MPa11,8c += LFf (A.4)
Figure A.3 — Calibration curve for bolt driving method (test range 3,0 – 16,0 [Mpa])
The procedure has been calibrated to commonly used sprayed concrete grades. In case of deviations — particularly as regards Moh’s hardness or maximum grain size of the aggregates — calibration has to beperformed.
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
prEN 14487-1:2002 (E)
33
Figure A.4 — Calibration curve for penetration needle method (maximum grain size 8, 11 [mm])
[ ] 0273,00018,0MPa16c −= Ff (figure A.4) (A.5)
Figure A.5 — Calibration curve for penetration needle method (maximum grain size 16 [mm])
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
prEN 14487-1:2002 (E)
34
Annex B(informative)
General Guidelines for Steel Fibres for Sprayed Concrete
B.1 General
This Annex B, gives recommendation for steel fibres used in sprayed concrete. This annex will be supersededwhen European Standards on Fibre for Concrete are available.
B.2 Informative References
EN ISO 9000 Series, Specification for Quality System.
prEN 10080-1:1999-10, Steel for the reinforcement of concrete - Weldable reinforcing steel - Part 1: Generalrequirements
B.3 Definitions
B.3.1Steel fibresSteel fibres are straight or deformed pieces of cold-drawn steel wire, straight or deformed cut sheet fibres, fibresmilled from steel blocks or melt extracted fibres which are suitable to be homogeneously mixed into concrete andmortar to be sprayed.
B.3.2LengthThe directly measured length is the distance between the outer ends of the steel fibre.The developed length is thedistance for deformed steel fibres that are stretched by straightening the steel fibre without deforming the crosssection.
B.3.3Diameter or equivalent diameterThe diameter of circular steel fibres is determined in accordance with Clause A.6c. The equivalent diameter of noncircular steel fibres is the diameter of the circle with area equal to the cross-sectional area of the non circular fibreand is determined in accordance with Clause A.6c. Later refer to diameter.
B.3.4Aspect ratioThe ratio of directly measured length to diameter or equivalent diameter of the fibre.
B.3.5Steel fibre shapeThe specific outer configuration of the steel fibres, both in the longitudinal direction and in the shape of the crosssection and also the possible surface treatments.
B.4 Symbols
The symbols listed below are defined as follows:
Af is the area of the cross section of the steel fibre, in mm2;
df is the diameter or equivalent diameter of the steel fibre, in mm;
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
prEN 14487-1:2002 (E)
35
ff is the tensile strength of the steel fibre, in MPa;
l f is the directly measured length of the steel fibre, in mm;
λf = l f /df is the aspect ratio of the steel fibre.
B.5 Characterisation and product specification
The steel fibres shall be characterised as listed below.
a) Steel fibres are divided into five general groups and defined in accordance with the basic material used for theproduction of the fibres.
Group I cold-drawn steel wire
Group II cut sheet fibres
Group III milled from steel blocks
Group IV melt extract
Group V other steel fibres
b) Steel fibres may be either straight or deformed. In the case of deformed steel fibres, the type of deformation willbe declared in the product data sheet.
c) Bundles steel fibres:
The type of bundling shall be declared in the product data sheet.
d) The product specifications of steel fibres have to include the following information:
trade mark and a fibre type designation
length (l f)
diameter (df)
steel fibre shape
tensile strength
possible additional layer
The characterisation concerns the declared values.
B.6 Determination of characteristic features
The following characteristic features have to be determined from 24 steel fibres randomly selected from a shipmentor test sample. The characterisation shall be done at least, for each shipment of 20 tons or less, unless the fibresare certified in accordance with ISO 9000 series or a similar system.
a) Trade mark and fibres’ type designation:
Use the designation used by the manufacturer or supplier
b) Length:
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
prEN 14487-1:2002 (E)
36
The average length of the 24 steel fibres and the standard deviation are determined. In the determination ofthe length of a steel fibre, a distinction can be made between the directly measured length and the developedlength.
The directly measured length is the distance between both ends measured with a calliper square. The averageof all the measured values is determined.
To determine the average developed length the total length of the 24 straightened steel fibres, joined togetherin one row, is measured and subsequently divided by the total number of 24 steel fibres.
c) Diameter:
In the case of circular steel fibres, the diameters of the 24 steel fibres are measured with a micrometer calliperand subsequently the average of the measured values is determined.
In case of non-circular cross-section, the average equivalent diameter is determined by first establishing thetotal weight of the 24 steel fibres. Subsequently, the volume of the steel fibres is determined on the basis of anassumed density of 7 850 kg/m3. Division of the volume by the overall developed length of the 24 steel fibresresults in the equivalent area of the cross-section, from which the equivalent diameter can be derived.
d) Aspect ratio of the steel fibre:
Subsequent to the determination of the average directly measured length and the equivalent diameter from the24 steel fibres, the aspect ratio can be established.
e) Steel fibre shape:
The shape of the steel fibre is checked on the basis of the descriptions and/or drawings provided by themanufacturer or the supplier.
f) Tensile strength:
The tensile strength of the 24 steel fibres is determined in conformity with the methodology described inprEN 10080-1:1999-10.
g) Additional coating:
If the steel fibres have been supplied with any coating (e.g. zinc coating), the characteristics of the coatingshall be given in the product data sheet.
B.7 Tolerances
The tolerances for the determination of the characteristics described in A.6 are given in Table B.1.
Table B.1 — Tolerances
Property Deviation of the individual valuerelative to the declared value
Deviation of the average valuerelative to the declared value
Length l f ± 10 % ± 3 %
(equivalent) diameter df ± 10 % ± 0,03 %
Tensile strength f f N/mm 2 ± 15 % ± 7,5 %
Length/diameter ratio ± 15 % ± 7.5 %
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
prEN 14487-1:2002 (E)
37
B.8 Packaging
The steel fibres have to be packed in such a way that they are sufficiently protected against detrimental effectduring transport and storage. Every delivery shall contain only one type of material and one single size, unlessotherwise agreed upon.
Every container has to be marked with the type of fibre, the net weight and the name or trade mark of themanufacturer.
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I
Lice
nsed
Cop
y: U
nive
rsity
of B
ath
Libr
ary,
Uni
vers
ity o
f Bat
h, 0
9 O
ctob
er 2
003,
Unc
ontr
olle
d C
opy,
(c)
BS
I