SIST-TS CEN/TS 1992-4-3:2009
(Main)Design of fastenings for use in concrete - Part 4-3: Anchor channels
Design of fastenings for use in concrete - Part 4-3: Anchor channels
1.1 General
1.1.6 This document relies on characteristic resistances and distances which are stated in a European
Technical Specification. In minimum the following characteristics should be given in a European Technical
Specification as base for the design methods of this CEN/TS.
- a s Rk , , N , c s Rk , , N , l s Rk , , N , s s Rk , , N , s s Rk , , V , l s Rk , , V , flex s Rk , , M , 0
s Rk, M
- NRk,p
- p ch α , α
- ccr,N, scr,N
- ccr,sp, scr,sp
- cmin, smin, hmin
- limitations on concrete strength classes of base material
- k5
- Ah, bch, d, hef, hch, Iy
- γMi partial factors for material see also CEN/TS 1992-4-1:XXXX, clause 4
1.4 Anchor channel loading
1.4.3 Actions not covered
The following actions are not covered by this CEN/TC:
- shear in the direction of the longitudinal axis of the channel
- fatigue loading
- seismic loading
This document relies on characteristic resistances and distances which are stated in a European Technical Specification. In minimum the following characteristics should be given in a European Technical Specification as base for the design methods of this CEN/TS.
Bemessung von Befestigungen in Beton - Teil 4-3: Ankerschienen
1.1 Allgemeines
1.1.6 Dieses Dokument stützt sich auf charakteristische Widerstände und Abstände, die in einer Europäischen Technischen Spezifikation festgelegt sind. Als Grundlage für die Bemessung nach dieser CEN/TS sollten in einer europäischen Technischen Spezifikation zumindest die folgenden charakteristischen Werte angegeben sein.
- a s Rk , , N , c s Rk , , N , l s Rk , , N , s s Rk , , N , s s Rk , , V , l s Rk , , V , flex s Rk , , M , 0
s Rk, M
- NRk,p
- p ch α , α
- ccr,N, scr,N
- ccr,sp, scr,sp
- cmin, smin, hmin
- Grenzwerte für die Betonfestigkeitsklasse des Verankerungsgrundes
- k5
- Ah, bch, d, hef, hch, Iy
- Teilsicherheitsbeiwert für den Materialwiderstand, siehe auch CEN/TS 1992-4-1:2008, Abschnitt 4
1.4 Ankerschiene, Beanspruchung
1.4.3 Nicht behandelte Beanspruchungen
Folgende Beanspruchungen sind durch diese CEN/TS nicht abgedeckt:
- Querbeanspruchung in Richtung Schienenlängsachse
- Ermüdungsbeanspruchung
- Erdbebenbeanspruchung
Conception-calcul des éléments de fixation pour béton - Partie 4-3 : Rails d'ancrage
1.1 Généralités
1.1.6 Ce document se fonde sur des résistances caractéristiques et distances spécifiées dans une
Spécification Technique européenne. Il convient qu’au minimum, les caractéristiques suivantes soient
données dans une Spécification Technique européenne comme base des méthodes de conception du
présent CEN/TS.
⎯ a s Rk , , N , c s Rk , , N , l s Rk , , N , s s Rk , , N , s s Rk , , V , l s Rk , , V , flex s Rk , , M , 0
s Rk, M
⎯ NRk,p
⎯ p ch α , α
⎯ ccr,N, scr,N
⎯ ccr,sp, scr,sp
⎯ cmin, smin, hmin
⎯ limites des classes de résistance de l’élément en béton
⎯ k5
⎯ Ah, bch, d, hef, hch, Iy
⎯ coefficients partiels γMi du matériau, voir aussi CEN/TS 1992-4-1:2009, Article 4
Projektiranje pritrjevanja za uporabo v betonu - 4-3. del: Sidrni kanali
General Information
Relations
Buy Standard
Standards Content (Sample)
SLOVENSKI STANDARD
SIST-TS CEN/TS 1992-4-3:2009
01-oktober-2009
Projektiranje pritrjevanja za uporabo v betonu - 4-3. del: Sidrni kanali
Design of fastenings for use in concrete - Part 4-3: Anchor channels
Bemessung von Befestigungen in Beton - Teil 4-3: Ankerschienen
Conception-calcul des éléments de fixation pour béton - Partie 4-3 : Rails d'ancrage
Ta slovenski standard je istoveten z: CEN/TS 1992-4-3:2009
ICS:
21.060.01 Vezni elementi na splošno Fasteners in general
91.080.40 Betonske konstrukcije Concrete structures
SIST-TS CEN/TS 1992-4-3:2009 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST-TS CEN/TS 1992-4-3:2009
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SIST-TS CEN/TS 1992-4-3:2009
TECHNICAL SPECIFICATION
CEN/TS 1992-4-3
SPÉCIFICATION TECHNIQUE
TECHNISCHE SPEZIFIKATION
May 2009
ICS 21.060.01; 91.080.40
English Version
Design of fastenings for use in concrete - Part 4-3: Anchor
channels
Conception-calcul des éléments de fixation pour béton - Bemessung von Befestigungen in Beton - Teil 4-3:
Partie 4-3 : Rails d'ancrage Ankerschienen
This Technical Specification (CEN/TS) was approved by CEN on 20 October 2008 for provisional application.
The period of validity of this CEN/TS is limited initially to three years. After two years the members of CEN will be requested to submit their
comments, particularly on the question whether the CEN/TS can be converted into a European Standard.
CEN members are required to announce the existence of this CEN/TS in the same way as for an EN and to make the CEN/TS available
promptly at national level in an appropriate form. It is permissible to keep conflicting national standards in force (in parallel to the CEN/TS)
until the final decision about the possible conversion of the CEN/TS into an EN is reached.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2009 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TS 1992-4-3:2009: E
worldwide for CEN national Members.
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Contents Page
Foreword .3
1 Scope .4
1.1 General .4
1.4 Anchor channel loading .4
1.4.3 Actions not covered .4
2 Normative references .4
3 Definitions and symbols .5
4 Basis of design .5
5 Determination of action effects .5
5.2 Derivation of forces acting on anchor channels .5
5.2.1 General .5
5.2.2 Tension loads .6
5.2.3 Shear loads .7
5.3 Tension forces in a supplementary reinforcement .8
5.3.3 Tension loads .8
5.3.4 Shear loads .8
6 Verification of ultimate limit state by elastic analysis .9
6.1 General .9
6.2 Tension loads .9
6.2.1 Required verifications .9
6.2.2 Design of supplementary reinforcement .9
6.2.3 Steel failure . 11
6.2.4 Pullout failure . 11
6.2.5 Concrete cone failure . 12
6.2.6 Splitting failure . 16
6.2.7 Blow-out failure . 17
6.2.8 Steel failure of the supplementary reinforcement . 18
6.2.9 Anchorage failure of the supplementary reinforcement in the concrete cone . 19
6.3 Shear loads . 19
6.3.1 Required verifications . 19
6.3.2 Design of reinforcement . 19
6.3.3 Steel failure . 21
6.3.4 Concrete pry-out failure . 22
6.3.5 Concrete edge failure . 22
6.3.6 Steel failure of supplementary reinforcement . 26
6.3.7 Anchorage failure of supplementary reinforcement in the concrete cone . 26
6.4 Combined tension and shear loads . 27
6.4.1 Anchor channels without supplementary reinforcement . 27
6.4.2 Anchor channels with supplementary reinforcement. 27
7 Fatigue . 28
8 Seismic . 28
2
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Foreword
This Technical Specification (CEN/TS 1992-4-3:2009) has been prepared by Technical Committee
CEN/TC 250 “Structural Eurocodes”, the secretariat of which is held by BSI.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
This Technical Specification CEN/TS 1992-4- 3 — Anchor Channels, describes the principles and
requirements for safety, serviceability and durability of anchor channels for use in concrete, together with
specific provisions for structures serving as base material. It is based on the limit state concept used in
conjunction with a partial factor method.
This Technical Specification does not provide information about the use of National Determined Parameters
(NDP).
CEN/TS 1992-4 'Design of fastenings for use in concrete' is subdivided into the following parts:
Part 1: General
Part 2: Headed fasteners
Part 3: Anchor channels
Part 4: Post-installed fasteners — Mechanical systems
Part 5: Post-installed fasteners — Chemical systems
Relation to CEN/TS 1992-4-1
The principles and requirements of Part 3 of this CEN/TS are additional to those in CEN/TS 1992-4-1, all the
clauses and sub-clauses of which also apply to Part 3 unless varied in this Part. Additional information is
presented under the relevant clauses/sub-clauses of CEN/TS 1992-4-1. The numbers for the clauses/sub-
clauses of Part 3 continue from the number of the last relevant clauses/sub-clauses of Part 1.
The above principles also apply to Figures and Tables in Part 3.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to announce this Technical Specification: Austria, Belgium, Bulgaria, Cyprus, Czech
Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and the United Kingdom.
3
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1 Scope
1.1 General
1.1.6 This document relies on characteristic resistances and distances which are stated in a European
Technical Specification. In minimum the following characteristics should be given in a European Technical
Specification as base for the design methods of this CEN/TS.
0
N , N , N , N , V , V , M , M
Rk,s,a Rk,s,c Rk,s,l Rk,s,s Rk,s,s Rk,s,l Rk,s,flex
Rk,s
N
Rk,p
α ,α
ch p
c , s
cr,N cr,N
c , s
cr,sp cr,sp
c , s , h
min min min
limitations on concrete strength classes of base material
k
5
A , b , d, h , h , I
h ch ef ch y
γ partial factors for material see also CEN/TS 1992-4-1:2009, clause 4
Mi
1.4 Anchor channel loading
1.4.3 Actions not covered
The following actions are not covered by this CEN/TC:
shear in the direction of the longitudinal axis of the channel;
fatigue loading;
seismic loading.
2 Normative references
This European Standard incorporates by dated or undated reference, provisions from other publications.
These normative references are cited at the appropriate places in the text and the publications are listed
hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply to
this European Standard only when incorporated in it by amendment or revision. For undated references the
latest edition of the publication referred to applies.
NOTE The following references to Eurocodes are references to European Standards and European Prestandards.
These are the only European documents available at the time of publication of this TS. National documents take
precedence until Eurocodes are published as European Standards.
EN 1992-1-1, Design of concrete structures — Part 1-1: General rules and rules for buildings
4
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CEN/TS 1992-4-1:2009, Design of fastenings for use in concrete — Part 4-1: General
3 Definitions and symbols
The definitions and symbols are given in CEN/TS 1992-4-1.
4 Basis of design
4.5.4 The following assumptions in respect to installation have been made in this CEN/TS. The installation
instructions should reflect them:
1) The anchor channel should be fixed to the formwork or auxiliary constructions in a way that no movement
of the anchor channel will occur during placing of reinforcement or during pouring and compacting of the
concrete.
2) Requirements for adequate compaction particularly under the head of the anchor and under the channel.
3) Requirements for inspection and approval of the correct installation of the anchor channels by
appropriately qualified personnel.
4) Placing anchor channels by only pushing them into the wet concrete is not allowed.
5) It is accepted to vibrate the anchor channels into the wet concrete immediately after pouring under the
following conditions:
The size and number of fastenings is limited to anchor channels with a length of <1 m if placed by
1 person, so that it can be placed simultaneously during vibrating by the available personnel. Longer
channels should be placed by at least 2 persons.
The installation is carried out according to a quality system.
The anchor channels are not moved after vibrating has been finished.
The concrete in the region of the anchor and the anchor channel is properly compacted.
5 Determination of action effects
5.2 Derivation of forces acting on anchor channels
5.2.1 General
5.2.1.6 The distribution of tension loads acting on the channel to the anchors may be calculated using a
beam on elastic support (anchors) with a partial restraint of the channel ends as statical system. The resulting
anchor forces depend significantly on the assumed anchor stiffness and degree of restraint. For shear loads
the load distribution is also influenced by the pressure distribution in the contact zone between channel and
concrete.
5.2.1.7 As a simplification for anchor channels with two anchors the loads on the anchors may be
calculated assuming a simply supported beam with a span length equal to the anchor spacing.
5.2.1.8 For anchor channels with more than two anchors as an alternative in the following the triangular
load distribution method to calculate the distribution of tension and shear loads to the anchors is introduced.
5.2.1.9 In the case of shear loads, this CEN/TS covers only shear loads acting on the channel
perpendicular to its longitudinal axis.
5
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5.2.2 Tension loads
5.2.2.1 This clause supersedes CEN/TS 1992-4-1:2009, 5.5.2.
5.2.2.2 The tension forces in each anchor due to a tension load acting on the channel are calculated
according to Equation (1), which assumes a linear load distribution over the influence length l and takes into
i
account the condition of equilibrium. The influence length l shall be calculated according to Equation (3). An
i
example for the calculation of the forces acting on the anchors is given in Figure 1.
a '
N = k ⋅ A ⋅ N (1)
i Ed
Ed,i
with
'
A ordinate at the position of the anchor i of a triangle with the unit height at the position of load N and
i
the base length 2l
i
1
k = (2)
n
A'
i
∑
1
0,05 0,5
l = 13 ⋅ I ⋅ s ≥ s [mm] (3)
i y
n number of anchors on the channel within the influence length I to either side of the applied load N
i Ed
(see Figure 1)
4
I moment of inertia of the channel [mm ], see Figure 3.2
y
s anchor spacing [mm]
The moment of inertia of the channel should be taken from the relevant European Technical Specification.
If several tension loads are acting on the channel a linear superimposition of the anchor forces for all loads
should be assumed.
If the exact position of the load on the channel is not known, the most unfavourable loading position should be
assumed for each failure mode (e.g. load acting over an anchor for the case of failure of an anchor by steel
rupture or pull-out and load acting between anchors in the case of bending failure of the channel).
The bending moment in the channel due to tension loads acting on the channel may be calculated assuming a
simply supported single span beam with a span length equal to the anchor spacing.
6
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l−1,25 s 1
' a a
A = = N = N = 0
2
Ed,1 Ed,5
l 6
l−0,25 s 5 1 2 1
' a
A = = N = ⋅ ⋅ N = N
3
Ed,2 Ed
l 6 6 3 9
l− 0,75 s 1 5 2 5
' a
A = = N = ⋅ ⋅ N = N
4
Ed,3 Ed
l 2 6 3 9
1 2 1 2 1
a
k = = N = ⋅ ⋅ N = N
Ed
Ed,4
' ' '
3 2 3 3
A + A + A
2 3 4
Figure 1 — Example for the calculation of anchor forces according to the triangular load distribution
method for an anchor channel with 5 anchors - the influence length is assumed as l = 1,5s
i
NOTE The assumption of a simply supported beam to calculate the moments is a simplification which neglects the
influence of partial end restraints, continuous beam action for channels with more than 2 anchors and catenary action after
yielding of the channel. The characteristic values of the moments of the resistance given in the European Technical
Specification take these effects into account. They may be larger than the plastic moment, calculated with the dimensions
of the channel and nominal yield strength of the steel.
5.2.3 Shear loads
5.2.3.1 Section 5.2.3.2 supersedes CEN/TS 1992-4-1:2009, 5.2.3.1. The provisions given in CEN/TS
1992-4-1:2009, 5.2.3.2 and 5.2.3.3 should be used to determine whether a shear load acts with or without a
lever arm on the special screw.
5.2.3.2 The shear forces of each anchor due to a shear load acting on the channel perpendicular to its
longitudinal axis may be calculated as described in 5.2.2.
NOTE Shear loads applied perpendicular to anchor channels are transferred by compression stresses in the
interface between channel and concrete mainly directly into the concrete and a small share to the anchors via bending of
the anchor channel. In addition for reasons of equilibrium the anchors are stressed by tension forces.
In the approach presented above it is assumed that shear forces are transferred by bending of the channel to the anchors
and by the anchors into the concrete. This simplified approach has been chosen to allow for simple interaction between
tension and shear forces acting on the channel.
7
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5.3 Tension forces in a supplementary reinforcement
5.3.3 Tension loads
The design forces N in the supplementary reinforcement should be calculated using the design load on
ED, re
the anchor.
5.3.4 Shear loads
The design tension force N in the supplementary reinforcement caused by the design shear force V
Ed
Ed,re
acting on a fixture is given by Equation (4).
e
s
N = V ( + 1) (4)
Ed,re Ed
z
with (see Figure 2):
e distance between reinforcement and shear force acting on the anchor channel
s
z internal lever arm of the concrete member
≈ 0,85 h'
≈ 0,85·(h - h - 0,5d )
ch s
2h
ef
h' ≤ min
2c
1
Figure 2 — Surface reinforcement to take up shear forces — detailing of reinforcement
If the supplementary reinforcement is not arranged in the direction of the shear force then this must be taken
into account in the calculation of the design tension force of the reinforcement.
In the case of different shear forces on the anchors of the anchor channel, Equation (4) should be solved for
h h
the shear load V of the most loaded anchor channel resulting in N .
Ed Ed,re
8
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6 Verification of ultimate limit state by elastic analysis
6.1 General
6.1.5 In addition to the failure modes given in CEN/TS 1992-4-1:2009, Figures 20 and 21, the failure modes
given in Figure 3 might occur.
Key
a) local failure of the channel lip
b) failure due to flexure of the channel
c) failure of the anchor
Figure 3 — Additional failure modes for anchor channels
6.2 Tension loads
6.2.1 Required verifications
The required verifications are given in Table 1.
6.2.1.1 For anchor channels without supplementary reinforcement the verifications of Table 1, lines 1 to 9
apply.
6.2.1.2 For anchor channels with supplementary reinforcement the verifications of Table 1, lines 1 to 6
and 8 to 11 apply.
6.2.2 Design of supplementary reinforcement
When the design relies on supplementary reinforcement, concrete cone failure according to Equation (7)
needs not to be verified but the supplementary reinforcement should be designed to resist the total load. The
reinforcement should be anchored adequately on both sides of the potential failure planes.
9
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Table 1 — Required verifications for channel bars under tension loading
Most unfavourable anchor or
Failure mode Channel
screw
a b
1 anchor N ≤ N = N /γ
Ed Rd,s,a Rk,s,a Ms
connection b
a
N ≤ N = N / γ
2
Ed Rd,s,c Rk,s,c Ms,ca
between anchor and channel
b
N ≤ N = N /γ
3 local flexure of channel lip
Ed
Steel Rd,s,l Rk,s,l Ms,l
failure
b
4 special screw N ≤ N = N /γ
Ed Rd,s Rk,s Ms
M ≤ M =
Ed
Rd,s,flex
5 flexure of channel
M /γ
Rk,s,flex Ms,flex
b
a
N ≤ N = N /γ
6 Pull-out failure
Ed Rd,p Rk,p Mp
c
a
N ≤ N = N /γ
7 Concrete cone failure
Ed Rd,c Rk,c Mc
a c
8 Splitting failure N ≤ N = N /γ
Ed Rd,sp Rk,sp Msp
a c
a
9 Blow-out failure N ≤ N = N /γ
Ed Rd,cb Rk,cb Mc
Steel failure of a b
10 N ≤ N = N /γ
Ed,re Rd,re Rk,re Ms,re
supplementary reinforcement
Anchorage failure of supplementary
a b
11 N ≤ N = N /γ
Ed,re Rd,a Rk,a Mc
reinforcement
a
not required for anchors with c > 0,5 h
ef
b
most loaded anchor or special screw
c
the load on the anchor in conjunction with the edge distance and spacing should be considered in determining the
most unfavourable anchor
The supplementary reinforcement to take up tension loads should comply with the following requirements (see
also Figure 4):
a) In general, for all anchors of a channel the same diameter of the reinforcement should be provided. It
2
should consist of ribbed reinforcing bars (f ≤ 500 N/mm ) with a diameter d not larger than 16 mm and
yk s
should be detailed in form of stirrups or loops with a mandrel diameter according to EN 1992-1-1.
b) The supplementary reinforcement should be placed as close to the anchors as practicable to minimise
the effect of eccentricity associated with the angle of the failure cone. Preferably, the supplementary
reinforcement should enclose the surface reinforcement. Only these reinforcement bars with a distance
≤ 0,75 h from the anchor should be assumed as effective.
ef,
c) The minimum anchorage length of supplementary reinforcement in the concrete failure cone is
min l = 4 d (anchorage with bends, hooks or loops) or min l = 10 d (straight bars with or without
1 s 1 s
welded transverse bars).
d) The supplementary reinforcement should be anchored outside the assumed failure cone with an
anchorage length l according to EN 1992-1-1.
bd
e) A surface reinforcement should be provided as shown in Figure 4a) designed to resist the forces arising
from the assumed strut and tie model, taking into account the splitting forces according to 6.2.6.
10
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For anchors channels located parallel to the edge of a concrete member or in a narrow concrete member, the
plane of the supplementary reinforcement shall be located perpendicular to the longitudinal axis of the channel
(see Figure 4).
Key
1 supplementary reinforcement
2 surface reinforcement
Figure 4 — Arrangement of supplementary reinforcement
6.2.3 Steel failure
The characteristic resistances N (failure of anchor), N (failure of the connection between anchor
Rk,s,a Rk,s,c
and channel), N (local failure by flexure of the channel lips), N (failure of the special screw) and
Rk,s,l Rk,s
M (failure by flexure of the channel) are given in the relevant European Technical Specification.
Rk,s,flex
6.2.4 Pullout failure
The characteristic resistance N for pullout failure of the anchor is given in the relevant European Technical
Rk,p
Specification.
NOTE The characteristic resistance N is limited by the concrete pressure under the head of the anchor
Rk,p
according to Equation (5):
N = 6 ⋅ A ⋅ f ⋅ψ (5)
Rk,p h ck,cube ucr,N
with
A load bearing area of the head of the anchor
h
π
2 2
= ()d − d in case of a round head (6)
h
4
f characteristic cube strength of the concrete strength class but noting the limitations given in the relevant
ck,cube
European Technical Specification.
11
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ψ = 1,0 for anchor channels in cracked concrete
ucr,N
= 1,4 for anchor channels in non-cracked concrete
6.2.5 Concrete cone failure
6.2.5.1 Characteristic resistance
The characteristic resistance of one anchor of a channel bar in case of concrete cone failure may be
calculated according to Equation (7).
0
N = N ⋅ α ⋅ α ⋅ α ⋅ ψ ⋅ ψ (7)
Rk, c s, N e, N c, N re, N ucr, N
Rk, c
The different factors in Equation (7) are given in the following sections.
6.2.5.2 Basic characteristic resistance of an anchor
The basic characteristic resistance of one anchor not influenced by adjacent anchors, edges or corners of the
concrete member located in cracked concrete is obtained by:
0 1,5
N = 8,5 ⋅α ⋅ f ⋅ h [N] (8)
ch ck, cube
Rk, c ef
with
α factor taking into account the influence of the channel on the concrete cone failure load. It is
ch
given in the relevant European Technical Specification.
≤ 1
f [N/mm²], characteristic cube strength of the concrete strength class but noting the limitations
ck,cube
given in the relevant European Technical Specification.
h [mm]
ef
6.2.5.3 Effect of neighbouring anchors
The influence of neighbouring anchors on the concrete cone resistance is taken into account by the factor α
s, N
according to Equation (9).
1
α = (9)
s,N
1,5
n
s N
i i
1+ 1− ⋅
∑
s N
cr,N 0
i=1
with (see Figure 5):
s distance between the anchor under consideration and the neighbouring anchors
i
≤ s
cr,N
s = 2 ⋅ (2,8 – 1,3 ⋅ h /180) ⋅ h ≥ 3 ⋅ h (10)
cr, N ef ef ef
N tension force of an influencing anchor
i
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N tension force of the anchor under consideration
0
n number of anchors within a distance s to both sides of the anchor under consideration
cr,N
Key
1 anchor under consideration
Figure 5 — Example of an anchor channel with different anchor tension forces
6.2.5.4 Effect of edges of the concrete member
The influence of an edge of the concrete member on the characteristic resistance is taken into account by the
factor α according to Equation (11).
e, N
c
1 0,5
α =( ) ≤1 (11)
e,N
c
cr,N
with
c edge distance of the anchor channel (see Figure 6a))
1
c characteristic edge distance
cr,N
= 0,5s = (2,8 − 1,3 ⋅ h /180) ⋅ h ≥ 1,5 ⋅ h (12)
cr,N
ef ef ef
With anchor channels located in a narrow concrete member with different edge distances c and c (see
1,1 1,2
Figure 6b)) the minimum value of c and c should be inserted in Equation (11).
1,1 1,2
13
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Figure 6 — Channel bar at an edge or in a narrow member
6.2.5.5 Influence of a corner of the concrete member
The influence of a corner of the concrete member on the characteristic resistance is taken into account by the
factor α according to Equation (13).
c, N
0,5
c
2
α = ≤ 1 (13)
c, N
c
cr, N
with
c corner distance of the anchor under consideration (see Figure 7).
2
If an anchor is influenced by two corners, then the factor α has to be calculated for the values c and c
c, N 2,1 2,2
and the product of the factors α should be inserted in Equation (7).
c, N
6.2.5.6 Effect of shell spalling
The shell spalling factor ψ takes account of the effect of a dense reinforcement for embedment depths
re,N
h < 100 mm:
ef
h
ef
ψ = 0,5 + ≤ 1 [-] (14)
re,N
200
with
h [mm]
ef
Irrespective of the embedment depth of the anchor channel, Ψ may be taken as 1,0 in the following cases:
re,N
a) Local to this anchor chan
...
SLOVENSKI STANDARD
oSIST-TS prCEN/TS 1992-4-3:2008
01-september-2008
Projektiranje pritrjevanja za uporabo v betonu - 3. del: Sidrni kanali
Design of fastenings for use in concrete - Part 3: Anchor channels
Bemessung von Befestigungen in Beton - Teil 3: Ankerschienen
Ta slovenski standard je istoveten z: prCEN/TS 1992-4-3
ICS:
21.060.01 Vezni elementi na splošno Fasteners in general
91.080.40 Betonske konstrukcije Concrete structures
oSIST-TS prCEN/TS 1992-4-3:2008 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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oSIST-TS prCEN/TS 1992-4-3:2008
TECHNICAL SPECIFICATION
FINAL DRAFT
prCEN/TS 1992-4-3
SPÉCIFICATION TECHNIQUE
TECHNISCHE SPEZIFIKATION
June 2008
ICS 21.060.01; 91.080.40
English Version
Design of fastenings for use in concrete - Part 3: Anchor
channels
Bemessung von Befestigungen in Beton - Teil 3:
Ankerschienen
This draft Technical Specification is submitted to CEN members for formal vote. It has been drawn up by the Technical Committee CEN/TC
250.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
Warning : This document is not a Technical Specification. It is distributed for review and comments. It is subject to change without notice
and shall not be referred to as a Technical Specification.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36 B-1050 Brussels
© 2008 CEN All rights of exploitation in any form and by any means reserved Ref. No. prCEN/TS 1992-4-3:2008: E
worldwide for CEN national Members.
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Contents Page
Foreword.3
1 Scope .4
1.1 General.4
1.4 Anchor channel loading.4
1.4.3 Actions not covered .4
2 Normative references .4
3 Definitions and symbols .5
4 Basis of design .5
5 Determination of action effects.5
5.2 Derivation of forces acting on anchor channels .5
5.2.1 General.5
5.2.2 Tension loads.6
5.2.3 Shear loads.7
5.3 Tension forces in a supplementary reinforcement .8
5.3.3 Tension loads.8
5.3.4 Shear loads.8
6 Verification of ultimate limit state by elastic analysis .9
6.1 General.9
6.2 Tension loads.9
6.2.1 Required verifications .9
6.2.2 Design of supplementary reinforcement.9
6.2.3 Steel failure.11
6.2.4 Pullout failure.11
6.2.5 Concrete cone failure .12
6.2.6 Splitting failure.16
6.2.7 Blow-out failure.16
6.2.8 Steel failure of the supplementary reinforcement.18
6.2.9 Anchorage failure of the supplementary reinforcement in the concrete cone .18
6.3 Shear loads.19
6.3.1 Required verifications .19
6.3.2 Design of reinforcement .20
6.3.3 Steel failure.21
6.3.4 Concrete pry-out failure .21
6.3.5 Concrete edge failure .21
6.3.6 Steel failure of supplementary reinforcement .25
6.3.7 Anchorage failure of supplementary reinforcement in the concrete cone.26
6.4 Combined tension and shear loads.26
6.4.1 Anchor channels without supplementary reinforcement.26
6.4.2 Anchor channels with supplementary reinforcement.27
7 Fatigue .27
8 Seismic .27
2
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Foreword
This document (prCEN/TS 1992-3:2008) has been prepared by Technical Committee CEN/TC 250 “Structural
Eurocodes”, the secretariat of which is held by BSI.
This document is currently submitted to the Formal Vote.
This Technical Specification CEN/TS 1992-4- 3 — Anchor Channels, describes the principles and
requirements for safety, serviceability and durability of anchor channels for use in concrete, together with
specific provisions for structures serving as base material. It is based on the limit state concept used in
conjunction with a partial factor method.
CEN/TS EN 1992-4 'Design of fastenings for use in concrete' is subdivided into the following parts:
Part 1: General
Part 2: Headed fasteners
Part 3: Anchor channels
Part 4: Post-installed fasteners –mechanical systems
Part 5: Post-installed fasteners – chemical systems
Relation to CEN/TS 1992-4-1
The principles and requirements of Part 3 of this CEN/TS are additional to those in CEN/TS 1992-4-1, all the
clauses and sub-clauses of which also apply to Part 3 unless varied in this Part. Additional information is
presented under the relevant clauses/sub-clauses of CEN/TS 1992-4-1. The numbers for the clauses/sub-
clauses of Part 3 continue from the number of the last relevant clauses/sub-clauses of Part 1.
The above principles also apply to Figures and Tables in Part 3.
3
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1 Scope
1.1 General
1.1.6 This document relies on characteristic resistances and distances which are stated in a European
Technical Specification. In minimum the following characteristics should be given in a European Technical
Specification as base for the design methods of this CEN/TS.
0
N , N , N , N , V , V , M , M
Rk,s,a Rk,s,c Rk,s,l Rk,s,s Rk,s,s Rk,s,l Rk,s,flex
Rk,s
N
Rk,p
α ,α
ch p
c , s
cr,N cr,N
c , s
cr,sp cr,sp
c , s , h
min min min
limitations on concrete strength classes of base material
k
5
A , b , d, h , h , I
h ch ef ch y
γ partial factors for material see also CEN/TS 1992-4-1:XXXX, clause 4
Mi
1.4 Anchor channel loading
1.4.3 Actions not covered
The following actions are not covered by this CEN/TC:
shear in the direction of the longitudinal axis of the channel
fatigue loading
seismic loading
2 Normative references
This European Standard incorporates by dated or undated reference, provisions from other publications.
These normative references are cited at the appropriate places in the text and the publications are listed
hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply to
this European Standard only when incorporated in it by amendment or revision. For undated references the
latest edition of the publication referred to applies.
NOTE The following references to Eurocodes are references to European Standards and European Prestandards.
These are the only European documents available at the time of publication of this TS. National documents take
precedence until Eurocodes are published as European Standards.
EN 1992-1-1, Design of concrete structures - Part 1-1: General rules and rules for buildings
4
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CEN/TS 1992-4-1:XXXX, Design of fastenings for use in concrete — Part 1: General
3 Definitions and symbols
The definitions and symbols are given in CEN/TS 1992-4-1.
4 Basis of design
4.5.4 The following assumptions in respect to installation have been made in this CEN/TS. The installation
instructions should reflect them:
1) The anchor channel should be fixed to the formwork or auxiliary constructions in a way that no movement
of the anchor channel will occur during placing of reinforcement or during pouring and compacting of the
concrete.
2) Requirements for adequate compaction particularly under the head of the anchor and under the channel.
3) Requirements for inspection and approval of the correct installation of the anchor channels by
appropriately
qualified personnel.
4) Placing anchor channels by only pushing them into the wet concrete is not allowed.
5) It is accepted to vibrate the anchor channels into the wet concrete immediately after pouring under the
following conditions:
The size and number of fastenings is limited to anchor channels with a length of <1 m if placed by
1 person, so that it can be placed simultaneously during vibrating by the available personnel. Longer
channels should be placed by at least 2 persons.
The installation is carried out according to a quality system.
The anchor channels are not moved after vibrating has been finished.
The concrete in the region of the anchor and the anchor channel is properly compacted.
5 Determination of action effects
5.2 Derivation of forces acting on anchor channels
5.2.1 General
5.2.1.6 The distribution of tension loads acting on the channel to the anchors may be calculated using a
beam on elastic support (anchors) with a partial restraint of the channel ends as statical system. The resulting
anchor forces depend significantly on the assumed anchor stiffness and degree of restraint. For shear loads
the load distribution is also influenced by the pressure distribution in the contact zone between channel and
concrete.
5.2.1.7 As a simplification for anchor channels with two anchors the loads on the anchors may be
calculated assuming a simply supported beam with a span length equal to the anchor spacing.
5.2.1.8 For anchor channels with more than two anchors as an alternative in the following the triangular
load distribution method to calculate the distribution of tension and shear loads to the anchors is introduced.
5
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5.2.1.9 In the case of shear loads, this CEN/TS covers only shear loads acting on the channel
perpendicular to its longitudinal axis.
5.2.2 Tension loads
5.2.2.1 This clause supersedes CEN/TS 1992-4-1:XXXX, 5.5.2.
5.2.2.2 The tension forces in each anchor due to a tension load acting on the channel are calculated
according to Equation (1), which assumes a linear load distribution over the influence length l and takes into
i
account the condition of equilibrium. The influence length l shall be calculated according to Equation (3). An
i
example for the calculation of the forces acting on the anchors is given in Figure 1.
a '
N = k ⋅ A ⋅ N (1)
Ed,i i Ed
with
'
A ordinate at the position of the anchor i of a triangle with the unit height at the position of load N and
i
the base length 2l
i
1
k = (2)
n
A'
i
∑
1
0,05 0,5
l = 13 ⋅ I ⋅ s ≥ s [mm] (3)
i y
n number of anchors on the channel within the influence length I to either side of the applied load N
i Ed
(see Figure 1)
4
I moment of inertia of the channel [mm ], see Figure 3.2
y
s anchor spacing [mm]
The moment of inertia of the channel should be taken from the relevant European Technical Specification.
If several tension loads are acting on the channel a linear superimposition of the anchor forces for all loads
should be assumed.
If the exact position of the load on the channel is not known, the most unfavourable loading position should be
assumed for each failure mode (e.g. load acting over an anchor for the case of failure of an anchor by steel
rupture or pull-out and load acting between anchors in the case of bending failure of the channel).
The bending moment in the channel due to tension loads acting on the channel may be calculated assuming a
simply supported single span beam with a span length equal to the anchor spacing.
6
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l−1,25 s 1
' a a
A = = N = N = 0
2
Ed,1 Ed,5
l 6
l−0,25 s 5 1 2 1
' a
A = = N = ⋅ ⋅ N = N
3
Ed,2 Ed
l 6 6 3 9
l− 0,75 s 1 5 2 5
' a
A = = N = ⋅ ⋅ N = N
4
Ed,3 Ed
l 2 6 3 9
1 2 1 2 1
a
k = = N = ⋅ ⋅ N = N
Ed,4
Ed
' ' '
3 2 3 3
A + A + A
2 3 4
Figure 1 — Example for the calculation of anchor forces according to the triangular load distribution
method for an anchor channel with 5 anchors - the influence length is assumed as l = 1,5s
i
NOTE The assumption of a simply supported beam to calculate the moments is a simplification which neglects the
influence of partial end restraints, continuous beam action for channels with more than 2 anchors and catenary action after
yielding of the channel. The characteristic values of the moments of the resistance given in the European Technical
Specification take these effects into account. They may be larger than the plastic moment, calculated with the dimensions
of the channel and nominal yield strength of the steel.
5.2.3 Shear loads
5.2.3.1 Section 5.2.3.2 supersedes CEN/TS 1992-4-1:xxxx, 5.2.3.1. The provisions given in CEN/TS
1992-4-1:xxxx, 5.2.3.2 and 5.2.3.3 should be used to determine whether a shear load acts with or without a
lever arm on the special screw.
5.2.3.2 The shear forces of each anchor due to a shear load acting on the channel perpendicular to its
longitudinal axis may be calculated as described in 5.2.2.
NOTE Shear loads applied perpendicular to anchor channels are transferred by compression stresses in the
interface between channel and concrete mainly directly into the concrete and a small share to the anchors via bending of
the anchor channel. In addition for reasons of equilibrium the anchors are stressed by tension forces.
In the approach presented above it is assumed that shear forces are transferred by bending of the channel to the anchors
and by the anchors into the concrete. This simplified approach has been chosen to allow for simple interaction between
tension and shear forces acting on the channel.
7
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5.3 Tension forces in a supplementary reinforcement
5.3.3 Tension loads
The design forces N in the supplementary reinforcement should be calculated using the design load on the
ED, re
anchor.
5.3.4 Shear loads
The design tension force N in the supplementary reinforcement caused by the design shear force V
Ed
Ed,re
acting on a fixture is given by Equation (4).
e
s
N = V ( +1) (4)
Ed,re Ed
z
with (see Figure 2):
e distance between reinforcement and shear force acting on the anchor channel
s
z internal lever arm of the concrete member
≈ 0,85 h'
≈ 0,85·(h - h - 0,5d )
ch s
2h
ef
h
'≤ min
2c
1
Figure 2 — Surface reinforcement to take up shear forces — detailing of reinforcement
If the supplementary reinforcement is not arranged in the direction of the shear force then this must be taken
into account in the calculation of the design tension force of the reinforcement.
In the case of different shear forces on the anchors of the anchor channel, Equation (4) should be solved for
h h
the shear load V of the most loaded anchor channel resulting in N .
Ed Ed,re
8
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6 Verification of ultimate limit state by elastic analysis
6.1 General
6.1.5 In addition to the failure modes given in CEN/TS 1992-4-1:XXXX, Figures 20 and 21, the failure
modes given in Figure 3 might occur.
Key
a) local failure of the channel lip
b) failure due to flexure of the channel
c) failure of the anchor
Figure 3 — Additional failure modes for anchor channels
6.2 Tension loads
6.2.1 Required verifications
The required verifications are given in Table 1.
6.2.1.1 For anchor channels without supplementary reinforcement the verifications of Table 1, lines 1 to 9
apply.
6.2.1.2 For anchor channels with supplementary reinforcement the verifications of Table 1, lines 1 to 6
and 8 to 11 apply.
6.2.2 Design of supplementary reinforcement
When the design relies on supplementary reinforcement, concrete cone failure according to Equation (7)
needs not to be verified but the supplementary reinforcement should be designed to resist the total load. The
reinforcement should be anchored adequately on both sides of the potential failure planes.
9
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Table 1 — Required verifications for channel bars under tension loading
Most unfavourable anchor or
Failure mode Channel
screw
b
a
1 anchor N ≤ N = N / γ
Ed Rd,s,a Rk,s,a Ms
connection
a b
2 N ≤ N = N / γ
Ed
Rd,s,c Rk,s,c Ms,ca
between anchor and channel
b
3 N ≤ N = N / γ
local flexure of channel lip
Steel
Ed
Rd,s,l Rk,s,l Ms,l
failure
b
4
special screw N ≤ N = N / γ
Ms
Ed Rd,s Rk,s
M ≤ M =
Ed
Rd,s,flex
5
flexure of channel
M / γ
Rk,s,flex Ms,flex
b
a
6 Pull-out failure N ≤ N = N / γ
Ed Rd,p Rk,p Mp
c
a
7 Concrete cone failure N ≤ N = N / γ
Ed Rd,c Rk,c Mc
c
a
8 Splitting failure N ≤ N = N / γ
Ed Rd,sp Rk,sp Msp
a c
a
9 Blow-out failure N ≤ N = N / γ
Mc
Ed Rd,cb Rk,cb
Steel failure of b
a
10
N ≤ N = N / γ
Ed,re Rd,re Rk,re Ms,re
supplementary reinforcement
Anchorage failure of supplementary
b
a
11 N ≤ N = N / γ
Ed,re Rd,a Rk,a Mc
reinforcement
a
not required for anchors with c > 0,5 h
ef
b
most loaded anchor or special screw
c
the load on the anchor in conjunction with the edge distance and spacing should be considered in determining the
most unfavourable anchor
The supplementary reinforcement to take up tension loads should comply with the following requirements (see
also Figure 4):
a) In general, for all anchors of a channel the same diameter of the reinforcement should be provided. It
2
should consist of ribbed reinforcing bars (f ≤ 500 N/mm ) with a diameter d not larger than 16 mm and
yk s
should be detailed in form of stirrups or loops with a mandrel diameter according to EN 1992-1-1.
b) The supplementary reinforcement should be placed as close to the anchors as practicable to minimise
the effect of eccentricity associated with the angle of the failure cone. Preferably, the supplementary
reinforcement should enclose the surface reinforcement. Only these reinforcement bars with a distance
≤ 0,75 h from the anchor should be assumed as effective.
ef,
c) The minimum anchorage length of supplementary reinforcement in the concrete failure cone is
min l = 4 d (anchorage with bends, hooks or loops) or min l = 10 d (straight bars with or without
1 s 1 s
welded transverse bars).
d) The supplementary reinforcement should be anchored outside the assumed failure cone with an
anchorage length l according to EN 1992-1-1.
bd
e) A surface reinforcement should be provided as shown in Figure 4a) designed to resist the forces arising
from the assumed strut and tie model, taking into account the splitting forces according to 6.2.6.
For anchors channels located parallel to the edge of a concrete member or in a narrow concrete member, the
plane of the supplementary reinforcement shall be located perpendicular to the longitudinal axis of the channel
(see Figure 4).
10
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Key
1 supplementary reinforcement
2 surface reinforcement
Figure 4 — Arrangement of supplementary reinforcement
6.2.3 Steel failure
The characteristic resistances N (failure of anchor), N (failure of the connection between anchor
Rk,s,a Rk,s,c
and channel), N (local failure by flexure of the channel lips), N (failure of the special screw) and
Rk,s,l Rk,s
M (failure by flexure of the channel) are given in the relevant European Technical Specification.
Rk,s,flex
6.2.4 Pullout failure
The characteristic resistance N for pullout failure of the anchor is given in the relevant European Technical
Rk,p
Specification.
NOTE The characteristic resistance N is limited by the concrete pressure under the head of the anchor according
Rk,p
to Equation (5):
N =6 ⋅ A ⋅ f ⋅ψ (5)
Rk,p h ck,cube ucr,N
with
A load bearing area of the head of the anchor
h
π
2 2
= ()d − d in case of a round head (6)
h
4
f characteristic cube strength of the concrete strength class but noting the limitations given in the relevant
ck,cube
European Technical Specification.
ψ = 1,0 for anchor channels in cracked concrete
ucr,N
= 1,4 for anchor channels in non-cracked concrete
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6.2.5 Concrete cone failure
6.2.5.1 Characteristic resistance
The characteristic resistance of one anchor of a channel bar in case of concrete cone failure may be
calculated according to Equation (7).
0
N = N ⋅ α ⋅ α ⋅ α ⋅ ψ ⋅ ψ (7)
Rk, c s, N e, N c, N re, N ucr, N
Rk,c
The different factors in Equation (7) are given in the following sections.
6.2.5.2 Basic characteristic resistance of an anchor
The basic characteristic resistance of one anchor not influenced by adjacent anchors, edges or corners of the
concrete member located in cracked concrete is obtained by
0 1,5
N = 8,5 ⋅ α ⋅ f ⋅ h [N] (8)
ch ck, cube
Rk, c ef
with
α factor taking into account the influence of the channel on the concrete cone failure load. It is
ch
given in the relevant European Technical Specification.
≤ 1
f [N/mm²], characteristic cube strength of the concrete strength class but noting the limitations
ck,cube
given in the relevant European Technical Specification.
h [mm]
ef
6.2.5.3 Effect of neighbouring anchors
The influence of neighbouring anchors on the concrete cone resistance is taken into account by the factor α
s, N
according to Equation (9).
1
α = (9)
s,N
1,5
n
s N
i i
1+ 1− ⋅
∑
s N
i=1
cr,N 0
with (see Figure 5):
s distance between the anchor under consideration and the neighbouring anchors
i
≤ s
cr,N
s = 2 ⋅ (2,8 – 1,3 ⋅ h /180) ⋅ h ≥ 3 ⋅ h (10)
cr, N ef ef ef
N tension force of an influencing anchor
i
N tension force of the anchor under consideration
0
n number of anchors within a distance s to both sides of the anchor under consideration
cr,N
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Key
1 anchor under consideration
Figure 5 — Example of an anchor channel with different anchor tension forces
6.2.5.4 Effect of edges of the concrete member
The influence of an edge of the concrete member on the characteristic resistance is taken into account by the
factor α according to Equation (11).
e, N
c
1 0,5
(11)
α =( ) ≤1
e,N
c
cr,N
with
c edge distance of the anchor channel (see Figure 6a))
1
c characteristic edge distance
cr,N
= 0,5s = (2,8 −1,3 ⋅ h /180) ⋅ h ≥ 1,5 ⋅ h (12)
cr,N ef ef ef
With anchor channels located in a narrow concrete member with different edge distances c and c (see
1,1 1,2
Figure 6b)) the minimum value of c and c should be inserted in Equation (11).
1,1 1,2
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Figure 6 — Channel bar at an edge or in a narrow member
6.2.5.5 Influence of a corner of the concrete member
The influence of a corner of the concrete member on the characteristic resistance is taken into account by the
factor α according to Equation (13).
c, N
0,5
c
2
α = ≤ 1 (13)
c, N
c
cr, N
with
c corner distance of the anchor under consideration (see Figure 7).
2
If an anchor is influenced by two corners, then the factor α has to be calculated for the values c and c
c, N 2,1 2,2
and the product of the factors α should be inserted in Equation (7).
c, N
6.2.5.6 Effect of shell spalling
The shell spalling factor ψ takes account of the effect of a dense reinforcement for embedment depths
re,N
h < 100 mm:
ef
h
ef
ψ = 0,5 + ≤ 1 [-] (14)
re,N
200
with
h [mm]
ef
Irrespective of the embedment depth of the anchor channel, Ψ may be taken as 1,0 in the following cases:
re,N
a) Local to this anchor channel reinforcement (any diameter) is provided at a spacing ≥ 150 mm, or
b) Reinforcement with a diameter of 10 mm or less is provided at a spacing > 100 mm.
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Key
a) Resistance of anchor 1 is calculated
b) Resistance of anchor 2 is calculated
c) Resistance of anchor 2 is calculated
d) Resistance of anchor 1 is calculated
Figure 7 — Definition of the corner distance of an anchor channel in the corner of a concrete member
6.2.5.7 Effect of the anchor channel position
The factor ψ takes account of the position of the anchor channel in cracked or non-cracked concrete.
ucr,N
ψ = 1,0 for anchors in cracked concrete (15)
ucr,N
= 1,4 for anchors in non-cracked concrete
6.2.5.8 Effect of a narrow member
For the case of anchor channels with h > 180 mm in an application with influence of neighbouring anchors
ef
and influence of an edge and 2 corners (Figure 7c)) located with edge distance less than c from the
cr,N
anchor under consideration the calculation according to Equation (7) leads to conservative results. More
precise results are obtained if the value h is substituted by the larger value of
ef
c
...
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