kSIST-TS FprCEN/TS 19103:2021

Eurocode 5: Design of Timber Structures - Structural design of timber-concrete composite structures - Common rules and rules for buildings

1.1   Scope of CEN/TS 19103
(1)   CEN/TS 19103 gives general design rules for timber-concrete composite structures.
(2)   It provides requirements for materials, design parameters, connections, detailing and execution for timber-concrete composite structures. Recommendations for environmental parameters (temperature and moisture content), design methods and test methods are given in the Annexes.
(3)   It includes rules common to many types of timber-concrete composite, but does not include details for the design of glued timber-concrete composites, nor for bridges.
NOTE   For the design of glued timber-concrete composites or bridges alternative references are available.
(4)   It covers the design of timber-concrete composite structures in both quasi-constant and variable environmental conditions. For ease of use, it provides simple design rules for quasi-constant environmental conditions and more complex rules for variable environmental conditions.
1.2   Assumptions
(1)   The general assumptions of EN 1990 apply.
(2)   CEN/TS 19103 is intended to be used in conjunction with EN 1990, EN 1991 (all parts), EN  1992 (all parts), EN  1994 (all parts), EN 1995 (all parts), EN 1998 (all parts) when timber structures are built in seismic regions, and ENs for construction products relevant to timber structures.

Eurocode 5: Bemessung und Berechnung von Holz-Beton-Verbundbauteilen - Allgemeine Regeln und Regeln für den Hochbau

1.1   Anwendungsbereich von FprCEN/TS 19103
(1) FprCEN/TS 19103 enthält grundlegende Bemessungsregeln für Holz-Beton-Verbundbauteile.
(2) Sie enthält Anforderungen an Baustoffe, an Bemessungsparameter, an Verbindungen, an konstruktive Ausführung sowie an die Ausführung von Holz-Beton-Verbundbauteilen. Empfehlungen für Umgebungsparameter (Temperatur und Holzfeuchte), Bemessungsverfahren und Prüfverfahren sind den Anhängen zu entnehmen.
(3) Sie enthält Regeln, die für viele Typen von Holz-Beton-Verbundwerkstoffen gelten. Die Bemessung von Verbundbauteilen mit geklebter Verbindung zwischen Holz und Beton oder von Brücken ist nicht Gegenstand dieses Dokumentes.
ANMERKUNG   Für die Bemessung von Verbundbauteilen mit geklebter Verbindung aus Holz und Beton oder Brücken sind Verweise auf andere Berechnungsvorschriften verfügbar.
(4) Sie behandelt die Bemessung von Holz-Beton-Verbundbauteilen sowohl unter quasi-konstanten als auch unter veränderlichen Umgebungsbedingungen. Für die Vereinfachung der Anwendung enthält das Dokument Bemessungsregeln für quasi-konstante Umgebungsbedingungen sowie komplexere Regeln für veränderliche Umgebungsbedingungen
1.2   Annahmen
(1) Es gelten die allgemeinen Annahmen nach EN 1990.
(2) FprCEN/TS 19103 ist vorgesehen zur Anwendung in Zusammenhang mit EN 1990, EN 1991 (alle Teile), EN 1992 (alle Teile), EN 1994 (alle Teile), EN 1995 (alle Teile), EN 1998 (alle Teile), für die Erdbebenbemessung , sowie mit den für Holztragwerke maßgebenden EN für Bauprodukte.

Eurocode 5 : Conception et calcul des structures en bois - Calcul des structures mixtes bois-béton - Règles communes et règles pour les bâtiments

Evrokod 5: Projektiranje lesenih konstrukcij - Projektiranje sestavljenih konstrukcij iz lesa in betona - Splošna pravila in pravila za stavbe

General Information

• Status: Not Published
• Public Enquiry End Date: 19-Jun-2021
• ICS: 91.010.30 - Technical aspects
• ICS: 91.080.20 - Timber structures
• ICS: 91.080.40 - Concrete structures
• ICS: 91.080.99 - Other structures
• Technical Committee: KON - Structures
• Current Stage: 5520 - Unique Acceptance Procedure (UAP) (Adopted Project)
• Start Date: 12-Apr-2021
• Due Date: 30-Aug-2021
• Completion Date: 04-Jun-2021
• Directive: 305/2011 - Regulation (eu) No 305/2011 of the European Parliament and of the Council of 9 march 2011 laying down harmonised conditions for the marketing of construction products and repealing council directive 89/106/eec
• Mandate: M/515 - Mandate for amending existing Eurocodes and extending the scope of structural Eurocodes
• Ref Project: FprCEN/TS 19103 - Eurocode 5: Design of Timber Structures - Structural design of timber-concrete composite structures - Common rules and rules for buildings

Standards Content (sample)

SLOVENSKI STANDARD
kSIST-TS FprCEN/TS 19103:2021
01-junij-2021
Evrokod 5: Projektiranje lesenih konstrukcij - Projektiranje sestavljenih
konstrukcij iz lesa in betona - Splošna pravila in pravila za stavbe
Eurocode 5: Design of Timber Structures - Structural design of timber-concrete
composite structures - Common rules and rules for buildings
Eurocode 5: Bemessung und Berechnung von Holz-Beton-Verbundbauteilen -
Allgemeine Regeln und Regeln für den Hochbau

Eurocode 5 : Conception et calcul des structures en bois - Calcul des structures mixtes

bois-béton - Règles communes et règles pour les bâtiments
Ta slovenski standard je istoveten z: FprCEN/TS 19103
ICS:
91.010.30 Tehnični vidiki Technical aspects
91.080.20 Lesene konstrukcije Timber structures
91.080.40 Betonske konstrukcije Concrete structures
kSIST-TS FprCEN/TS 19103:2021 en,fr,de

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

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kSIST-TS FprCEN/TS 19103:2021
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kSIST-TS FprCEN/TS 19103:2021
FINAL DRAFT
TECHNICAL SPECIFICATION
FprCEN/TS 19103
SPÉCIFICATION TECHNIQUE
TECHNISCHE SPEZIFIKATION
April 2021
ICS 91.080.99; 91.080.20; 91.010.30
English Version
Eurocode 5: Design of Timber Structures - Structural
design of timber-concrete composite structures - Common
rules and rules for buildings

Eurocode 5 : Conception et calcul des structures en Eurocode 5: Bemessung und Berechnung von Holz-

bois - Calcul des structures mixtes bois-béton - Règles Beton-Verbundbauteilen - Allgemeine Regeln und

communes et règles pour les bâtiments Regeln für den Hochbau

This draft Technical Specification is submitted to CEN members for Vote. It has been drawn up by the Technical Committee

CEN/TC 250.

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

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

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

United Kingdom.

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

aware and to provide supporting documentation.

Warning : This document is not a 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
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels

© 2021 CEN All rights of exploitation in any form and by any means reserved Ref. No. FprCEN/TS 19103:2021 E

worldwide for CEN national Members.
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FprCEN/TS 19103:2021 (E)
Contents Page

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

0 Introduction ..................................................................................................................................................... 5

1 Scope ................................................................................................................................................................... 7

1.1 Scope of FprCEN/TS 19103 ......................................................................................................................... 7

1.2 Assumptions ..................................................................................................................................................... 7

2 Normative references ................................................................................................................................... 7

3 Terms, definitions and symbols ................................................................................................................ 8

3.1 Terms and definitions .................................................................................................................................. 8

3.2 Symbols and abbreviations ........................................................................................................................ 9

4 Basis of design ............................................................................................................................................... 15

4.1 General rules .................................................................................................................................................. 15

4.2 Principles of limit state design ................................................................................................................ 15

4.3 Basic variables .............................................................................................................................................. 16

4.4 Verification using the partial factor method ...................................................................................... 21

5 Materials .......................................................................................................................................................... 22

5.1 Quasi-constant environmental conditions ......................................................................................... 22

5.2 Variable environmental conditions....................................................................................................... 23

6 Durability ........................................................................................................................................................ 23

6.1 General ............................................................................................................................................................. 23

6.2 Timber decking for composite slabs in buildings ............................................................................ 23

6.3 Resistance to corrosion .............................................................................................................................. 23

7 Structural analysis ....................................................................................................................................... 24

7.1 Modelling of the composite structure ................................................................................................... 24

7.2 Propping .......................................................................................................................................................... 28

8 Ultimate limit states .................................................................................................................................... 28

8.1 General ............................................................................................................................................................. 28

8.2 Beams and slabs – Verification of cross-sections ............................................................................. 28

8.3 Walls ................................................................................................................................................................. 32

9 Serviceability limit states .......................................................................................................................... 33

9.1 General ............................................................................................................................................................. 33

9.2 Deflection ........................................................................................................................................................ 33

9.3 Vibration ......................................................................................................................................................... 33

9.4 Cracking of concrete .................................................................................................................................... 34

10 Connections .................................................................................................................................................... 36

10.1 General ............................................................................................................................................................. 36

10.2 Mechanical properties obtained from test ......................................................................................... 36

10.3 Mechanical properties determined according to this Technical Specification ..................... 36

10.4 Detailing .......................................................................................................................................................... 43

11 Detailing and execution ............................................................................................................................. 43

11.1 General ............................................................................................................................................................. 43

11.2 Detailing of the cross-section................................................................................................................... 44

11.3 Detailing of the shear connection and influence of execution ..................................................... 44

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FprCEN/TS 19103:2021 (E)

Annex A (informative) Yearly variations of moisture content averaged over the timber cross-

section for timber-concrete composite structures under variable environmental

conditions ....................................................................................................................................................... 46

A.1 Use of this Annex .......................................................................................................................................... 46

A.2 Scope and field of application ................................................................................................................. 46

A.3 Yearly variations of timber moisture content ................................................................................... 46

Annex B (informative) Calculation of the effect of inelastic strains ....................................................... 49

B.1 Use of this Annex .......................................................................................................................................... 49

B.2 Scope and field of application ................................................................................................................. 49

B.3 Effective bending stiffness ........................................................................................................................ 50

B.4 Bending moment in the concrete slab (sub. 1) and the timber beam (sub. 2) ...................... 52

B.5 Axial forces ..................................................................................................................................................... 52

B.6 Shear force in the connection due to shrinkage ............................................................................... 53

Annex C (informative) Experimental determination of the load-carrying capacity and stiffness

of timber to concrete connections ......................................................................................................... 55

C.1 Use of this Annex .......................................................................................................................................... 55

C.2 Scope and field of application ................................................................................................................. 55

C.3 Specimen configuration ............................................................................................................................ 55

C.4 Testing protocol ........................................................................................................................................... 56

C.5 Determination of mechanical properties ........................................................................................... 57

Bibliography ................................................................................................................................................................ 58

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FprCEN/TS 19103:2021 (E)
European foreword

This document (FprCEN/TS 19103:2021) has been prepared by Technical Committee CEN/TC 250

“Structural Euro-codes”, the secretariat of which is held by BSI. CEN/TC 250 is responsible for all

Structural Eurocodes and has been assigned responsibility for structural and geotechnical design matters

by CEN.
This document is currently submitted to the Vote on TS.

This document has been prepared under Mandate M/515 issued to CEN by the European Commission

and the European Free Trade Association.

This document has been drafted to be used in conjunction with relevant execution, material, product and

test standards, and to identify requirements for execution, materials, products and testing that are relied

upon by this document.
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kSIST-TS FprCEN/TS 19103:2021
FprCEN/TS 19103:2021 (E)
0 Introduction
0.1 Introduction to the Eurocodes

The Structural Eurocodes comprise the following standards generally consisting of a number of parts:

— EN 1990 Eurocode: Basis of structural design;
— EN 1991 Eurocode 1: Actions on structures;
— EN 1992 Eurocode 2: Design of concrete structures;
— EN 1993 Eurocode 3: Design of steel structures;
— EN 1994 Eurocode 4: Design of composite steel and concrete structures;
— EN 1995 Eurocode 5: Design of timber structures;
— EN 1996 Eurocode 6: Design of masonry structures;
— EN 1997 Eurocode 7: Geotechnical design;
— EN 1998 Eurocode 8: Design of structures for earthquake resistance;
— EN 1999 Eurocode 9: Design of aluminium structures.
— New Eurocodes under development
0.2 Introduction to EN 1995 (all parts)

(1) EN 1995 (all parts)applies to the design of buildings and civil engineering works in timber (solid

timber, sawn, planed or in pole form, glued laminated timber or wood-based structural products, e.g.

LVL) or wood-based panels jointed together with adhesives or mechanical fasteners. It complies with the

principles and requirements for the safety and serviceability of structures and the basis of design and

verification given in EN 1990.

(2) EN 1995 (all parts) is concerned only with requirements for mechanical resistance, serviceability,

durability and fire resistance of timber structures. Other requirements concerning thermal or sound

insulation, for example, are not considered.
(3) EN 1995 (all parts) is subdivided into various parts:
— EN 1995-1 General;
— EN 1995-2 Bridges.

(4) EN 1995-1 “General” in itself does not exist as a physical document, but comprises the following two

separate parts:
— EN 1995-1-1 General – Common rules and rules for buildings;
— EN 1995-1-2 General – Structural fire design.
EN 1995-2 refers to the General rules in EN 1995-1-1.
This document supplements EN 1995.
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0.3 Verb forms used in this Technical Specification

The verb “shall” expresses a requirement strictly to be followed and from which no deviation is permitted

in order to comply with the Eurocodes.

The verb “should” expresses a highly recommended choice or course of action. Subject to national

regulation and/or any relevant contractual provisions, alternative approaches may be used/adopted

where technically justified.

The verb "may” expresses a course of action permissible within the limits of the Eurocodes.

The verb “can” expresses possibility and capability; it is used for statements of fact and clarification of

concepts.
0.4 National annex for FprCEN/TS 19103

This document provides values within notes, indicating where national choices can be made. Therefore,

a national document implementing FprCEN/TS 19103 can have a National Annex containing all

Nationally Determined Parameters to be used for the assessment of buildings and civil engineering works

in the relevant country.
National choice is allowed in FprCEN/TS 19103 through the following subclauses:
• 4.3.1.2(5) Average timber moisture content due to the environmental conditions
• 4.4.1.1 Partial factor for shrinkage action
• 4.4.1.2 Partial factor for temperature action
• 4.4.1.2 Partial factor for moisture content action
• 4.4.2 Partial factor for connection shear strength

National choice is allowed in FprCEN/TS 19103 on the application of the following informative annexes:

• Annex A Yearly variations of moisture content averaged over the timber cross-section for timber-

concrete composite structures in variable environmental conditions

The National Annex can contain, directly or by reference, non-contradictory complementary information

for ease of implementation, provided it does not alter any provisions of the Eurocodes.

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FprCEN/TS 19103:2021 (E)
1 Scope
1.1 Scope of FprCEN/TS 19103

(1) FprCEN/TS 19103 gives general design rules for timber-concrete composite structures.

(2) It provides requirements for materials, design parameters, connections, detailing and execution for

timber-concrete composite structures. Recommendations for environmental parameters (temperature

and moisture content), design methods and test methods are given in the Annexes.

(3) It includes rules common to many types of timber-concrete composite, but does not include details

for the design of glued timber-concrete composites, nor for bridges.

NOTE For the design of glued timber-concrete composites or bridges alternative references are available.

(4) It covers the design of timber-concrete composite structures in both quasi-constant and variable

environmental conditions. For ease of use, it provides simple design rules for quasi-constant

environmental conditions and more complex rules for variable environmental conditions.

1.2 Assumptions
(1) The general assumptions of EN 1990 apply.

(2) FprCEN/TS 19103 is intended to be used in conjunction with EN 1990, EN 1991 (all parts), EN 1992

(all parts), EN 1994 (all parts), EN 1995 (all parts), EN 1998 (all parts) when timber structures are built

in seismic regions, and ENs for construction products relevant to timber structures.

2 Normative references

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

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

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

NOTE See the Bibliography for a list of other documents cited that are not normative references, including

those referenced as recommendations (i.e. in ‘should’ clauses), permissions (‘may’ clauses), possibilities ('can'

clauses), and in notes.
EN 1990:2002 , Eurocode - Basis of structural design
EN 1991 (all parts), Eurocode 1: Actions on structures

EN 1991-1-5:2003, Eurocode 1: Actions on structures - Part 1-5: General actions - Thermal actions

EN 1992-1-1:2004 , Eurocode 2: Design of concrete structures - Part 1-1: General rules and rules for

buildings
EN 1993-1-8, Eurocode 3: Design of steel structures - Part 1-8: Design of joints

EN 1994-1-1:2004, Eurocode 4: Design of composite steel and concrete structures - Part 1-1: General rules

and rules for buildings
1) As impacted by EN 1990:2002/A1:2005.
2) As impacted by EN 1992-1-1:2004/A1:2014.
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EN 1994-2:2005, Eurocode 4 - Design of composite steen and concrete structures - Part 2: General rules and

rules for bridges

EN 1995-1-1:2004 , Eurocode 5: Design of timber structures - Part 1-1: General - Common rules and rules

for buildings
EN 14592, Timber structures - Dowel-type fasteners - Requirements
3 Terms, definitions and symbols
3.1 Terms and definitions

For the purposes of this document, the terms and definitions given in EN 1990, EN 1995-1-1 and the

following apply.
3.1.1
continuous fastener
fastener that is continuous along the length of the timber component
3.1.2
connection

any device or system formed of connected parts and an associated fastener or fasteners as well as, where

applicable, notches, which resists slide and transfers the related shear force at the interface between

timber and concrete

Note 1 to entry: Examples include dowel-type fasteners of any material, notches, plates and continuous fasteners,

any of which can be either mechanically fixed or bonded.
Note 2 to entry: Staples fall beyond the scope of this standard.
3.1.3
inelastic strain

strain which is caused not by stresses but by shrinkage, swelling or thermal expansion, for example

3.1.4
moisture content
mass of water in wood, expressed as a percentage of its oven-dry mass
3.1.5
quasi-constant environmental conditions
environmental conditions where
— timber is installed close to its expected moisture content in use mc ; and
use

— for softwood timber, the variation of average moisture content in use (Δmc, see Formula 4.5) does

not exceed 6 %; and
— the temperature variations of the air do not exceed 20 °C

Note 1 to entry: The indoor conditions of a heated building are a typical example of quasi-constant conditions.

3) As impacted by EN 1995-1-1:2004/A1:2008 and EN 1995-1-1:2004/A2:2014.
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FprCEN/TS 19103:2021 (E)
3.1.6
shrinkage of concrete
decrease in dimension of a piece of concrete due to the hardening process
3.1.7
shrinkage of timber
decrease in dimension of a piece of timber due to reduction of moisture content
3.1.8
swelling of timber
increase in dimension of a piece of timber due to increase of moisture content
3.1.9
thermal expansion
linear thermal expansion between given temperatures
3.1.10
variable environmental conditions
conditions that do not comply with quasi-constant environmental conditions

Note 1 to entry: Typical examples where variable environmental conditions can be experienced are balconies,

unheated roof spaces and outdoor covered and uncovered spaces.
3.2 Symbols and abbreviations

For the purposes of this document, the symbols given in EN 1995-1-1 and the following apply.

Latin upper-case letters
A Area of cross-section 1
A Area of cross-section 2
A Area of longitudinal reinforcement in concrete flange
A Effective area of the concrete cross-section
conc,ef
A Area of longitudinal reinforcement in concrete flange
Area of transverse reinforcement in concrete flange
A Area of the timber cross-section
tim

Coefficient which considers the interaction between vertical load q and inelastic

J,sls
strains in terms of slip in the joint
C Coefficient which correlates the inelastic strains with a fictitious load
p,sls
E Modulus of elasticity of cross-section 1
E Modulus of elasticity of cross-section 2
E Modulus of elasticity of concrete
conc
E Effective long-term modulus of elasticity of concrete
conc,fin
E Characteristic combination of actions
E Quasi-permanent combination of actions
q,per
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FprCEN/TS 19103:2021 (E)
E Fundamental combination of actions

E Design value of the modulus of elasticity of the steel reinforcement as given in,

EN 1992-1-1:2004, 3.2.7
E Mean modulus of elasticity of timber parallel to the grain
tim
E Effective long-term modulus of elasticity of timber parallel to the grain
tim,fin
(EI) Bending stiffness of the cross-section i
(EI) Effective bending stiffness according to EN 1995-1-1:2004, Annex B
ef,EC5-AnnexB

(EI) Modified effective bending stiffness according to EN 1995-1-1:2004, Annex B, which

ef,sls
accounts for the interaction between vertical load and inelastic strains
F Characteristic axial withdrawal capacity of the fastener
ax,Rk
Estimated load-carrying capacity as defined in accordance with EN 26891 and used
est
in determining the mean slip modulus for ultimate limit states

F Characteristic load-carrying capacity in an Annex C test, as determined in accordance

max
with EN 26891
F Design load-carrying capacity for a notched connection
F Design tensile force between the timber and the concrete cross-section
t,Ed
F Design shear force per connection
v,Ed
Design load-carrying capacity per connection
v,Rd
F Characteristic connection shear strength
v,Rk
F Characteristic load-carrying capacity in shear per connection at time tc
v,R,tc,k
I Moment of inertia of cross-section 1
I Moment of inertia of cross-section 2
I Moment of inertia of the timber cross-section
tim
K Stiffness of the connection
K Maximum stiffness of the connection
max
Minimum stiffness of the connection
min
K Reference stiffness of connection
ref
Slip modulus for serviceability limit states
ser
K Final slip modulus
ser,fin
K Mean slip modulus for serviceability at time tc
ser,tc
K Instantaneous slip modulus of the connection for ultimate limit states
K Final slip modulus for ultimate limit states
u,fin
K Slip modulus for ultimate limit states at time tc
u,tc
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L Span of the beam

M(q + 0.8p ) Resulting bending moment due to external loads and part (80 %) of the fictitious load

d sls
equivalent to inelastic strains
M(q ) Resulting bending moment due to external load only
M Bending moment of component i
M Maximum bending moment in cross-section 2
max,2
M Bending moment in the timber cross-section
tim
N Axial force in cross-section i
Maximum axial force in cross-section 2
max,2
N Axial force in the timber cross-section
tim
T Initial average temperature in the concrete at time tc
0,conc
T Initial average temperature in the timber at time tc
0,tim
T Maximum temperature in the concrete (averaged over the cross-section)
max,conc
T Maximum temperature in the timber (averaged over the cross-section)
max,tim
T Minimum temperature in the concrete (averaged over the cross-section)
min,conc
T Minimum temperature in the timber (averaged over the cross-section)
min,tim
V Effective maximum shear force
max
V(q ) Resulting shear force due to external load
Ultimate slip determined in an Annex C test in accordance with EN 12512
X Design value of a strength property of timber or a wood-based product
Latin lower-case letters
a Distance
a spacing of fasteners parallel to the grain spacing of the fasteners
a Distance from the centroid of cross-section 1 to the centroid of the effective
1↔c
composite cross-section
a Distance between the fastener and the unloaded edge
a Distance between the fastener and the loaded edge
a spacing of fasteners perpendicular to the grain spacing of the fasteners

a Cross-sectional area of the transverse reinforcement of the concrete flange when

checking in-plane shear in the concrete

a Cross-sectional area of the longitudinal reinforcement of the concrete flange when

checking in-plane shear in the concrete
b Width of the concrete
conc
b Effective width of the concrete
conc,ef
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b Notch width
b Width of the timber
tim
b Width of the timber element (in verification of concrete for in-plane shear)
c Minimum concrete cover for durability of steel reinforcement
min,dur
c Nominal concrete cover
nom
d Fastener diameter or rebar diameter
d Diameter of the aggregate
d Diameter of the concrete reinforcement bar diameter
f Design value of the compressive strength of concrete
f Characteristic compressive cylinder strength of the concrete at 28 days
f Design value of the tensile strength of concrete
ctd
f characteristic embedment strength of the concrete member for evaluation of the
c,h,2,k
load-carrying capacity based on the Johansen models;
Effective design shear strength for the concrete
vcd
f Design shear strength of the timber member
v,t,d
f Design value of the yield strength of steel reinforcement
h Nominal height of the connector
s,conn
h Thickness of the concrete flange
h Notch depth
k Deformation factor of timber
def
k ' Deformation factor for connections between concrete and timber
def

k Modification factor for duration of load and moisture content for timber strength

mod

k ' Modification factor for duration of load and moisture content for the strength of

mod
connections between concrete and timber

k Mean slip modulus for serviceability limit states, determined from Annex C tests in

accordance with EN 26891
k Coefficient for concrete, taking into account the effect of high su
...