1 EUROCODES A tool for building safety and reliability enhancement Introduction to EN 1990 – Section 6 Workshop on Eurocodes: Training the trainers Moscow - 09 December - 10 December, 2010 Section 6: Verification by the partial factor method Annex B: Management of structural reliability for construction works Jean-Armand Calgaro Chairman of CEN/TC250 TC250

2 EUROCODES A tool for building safety and reliability enhancement Section 6 - Verification by the partial factor method 6.1General 6.2Limitations and simplifications 6.3Design values 6.3.1Design values of actions 6.3.2Design values of the effects of actions 6.3.3Design values of material properties 6.3.4Design values of geometrical data 6.3.5Design resistance 6.4Ultimate limit states 6.4.1Verifications : General 6.4.2Verifications of static equilibrium and resistance 6.4.3Combination of actions 6.4.4Partial factors for actions and combinations of actions 6.4.5Partial factors for materials 6.5Serviceability limit states 6.5.1Verifications of serviceability 6.5.2Performance criteria 6.5.3Combination of actions 6.5.4Partial factors for actions 6.5.5Partial factors for materials Introduction to EN 1990 – Section 6

3 EUROCODES A tool for building safety and reliability enhancement Turkstra’s Rule (1972) In the set of variable actions to be applied to a construction works, one of these variable actions is selected and considered as the leading action and the other actions are accompanying actions; they are taken into account in calculations with their combination value. The set including permanent actions, the leading variable action and the variable accompanying actions form a combination of actions. COMBINATIONS OF ACTIONS : PRINCIPLE Introduction to EN 1990 – Section 6

4 EUROCODES A tool for building safety and reliability enhancement FiFiFiFi F k,i F d,i =  f,i F k,i E(F d,i ; a d ) E d =  Sd E(F d,i ; a d ) E d = E(  F,i F k,i ; a d )  F,i =  f,i  Sd Action Characteristic value of the action Design value of the action Effect of actions Design value of action effect Design value of action effect (simplified expression) ACTIONS Introduction to EN 1990 – Section 6

5 EUROCODES A tool for building safety and reliability enhancement Key : a d a d Design value of geometrical data  f  f Partial factor for actions, which takes account of the possibility of unfavourable deviations of the action values from the representative values  Sd  Sd Partial factor associated with the uncertainty of the action and/or action effect model   is 1,00 or  0,  1, or  2 Introduction to EN 1990 – Section 6

6 EUROCODES A tool for building safety and reliability enhancement XiXiXiXi X k,i X d,i = (  i /  m,i )X k,i R(X d,i ; a d ) R d = (1/  Rd )R(X d,i ; a d ) R d = R((  i /  M,i )X k,i ; a d )  M,i =  m,i  Rd Material property Characteristic value of the material property Design value of the material property Structural resistance Design value of the structural resistance Design value of the structural resistance (simplified expression) RESISTANCES Introduction to EN 1990 – Section 6

7 EUROCODES A tool for building safety and reliability enhancement Key a d Design value of geometrical data  m Partial factor for a material property  Rd Partial factor associated with the uncertainty of the resistance model  Conversion factor taking account of : - volume and scale effects, - effects of temperature and moisture, - and any other appropriate factor. Introduction to EN 1990 – Section 6

8 EUROCODES A tool for building safety and reliability enhancement 6.4Ultimate limit states Introduction to EN 1990 – Section 6

9 EUROCODES A tool for building safety and reliability enhancement Ultimate Limit-States EQU – STR – GEO Introduction to EN 1990 – Section 6

10 EUROCODES A tool for building safety and reliability enhancement FAT EQU STR GEO Introduction to EN 1990 – Section 6

11 EUROCODES A tool for building safety and reliability enhancement Verifications of static equilibrium and resistance Ultimate limit states of static equilibrium (EQU) : E d,dst  E d,stb Ultimate limit states of resistance (STR/GEO) : E d  R d 6.5 Serviceability limit states E d  C d C d is the limiting design value of the relevant serviceability criterion. E d is the design value of the effects of actions specified in the serviceability criterion, determined on the basis of the relevant combination. Introduction to EN 1990 – Section 6

12 EUROCODES A tool for building safety and reliability enhancement Expression (6.10) Expressions (6.10a) and (6.10b) Ultimate limit states of STR/GEO - Fundamental combination for persistent and transient design situations    1,00 0,85    1,00 Introduction to EN 1990 – Section 6

13 EUROCODES A tool for building safety and reliability enhancement EN ULS Verification (Persistent and Transient Design Situations) E d = E {  j≥1  G,j G k,j “+”  p P “+”  Q,1 Q k,1 “+”  i>1  Q,i ψ 0,i  Q k,i } E d ≤ R d Applying Equation 6.10 from EN1990: Introduction to EN 1990 – Section 6

14 EUROCODES A tool for building safety and reliability enhancement EN ULS Verification (Persistent and Transient Design Situation) E d = E {  j≥1  G,j G k,j “+”  p P “+”  Q,1 Q k,1 “+”  i>1  Q,i ψ 0,i  Q k,i } Design effect or design value of action effects Introduction to EN 1990 – Section 6

15 EUROCODES A tool for building safety and reliability enhancement E d = E {  j≥1  G,j G k,j “+”  p P “+”  Q,1 Q k,1 “+”  i>1  Q,i ψ 0,i  Q k,i } Design effect Effect of EN ULS Verification (Persistent and Transient Design Situation) Introduction to EN 1990 – Section 6

16 EUROCODES A tool for building safety and reliability enhancement E d = E {  j≥1  G,j G k,j “+”  p P “+”  Q,1 Q k,1 “+”  i>1  Q,i ψ 0,i  Q k,i } Design effect Effect of Permanent actions EN ULS Verification (Persistent and Transient Design Situation) Introduction to EN 1990 – Section 6

17 EUROCODES A tool for building safety and reliability enhancement E d = E {  j≥1  G,j G k,j “+”  p P “+”  Q,1 Q k,1 “+”  i>1  Q,i ψ 0,i  Q k,i } Design effect Effect of Permanent actions Combined with EN ULS Verification (Persistent and Transient Design Situation) Introduction to EN 1990 – Section 6

18 EUROCODES A tool for building safety and reliability enhancement E d = E {  j≥1  G,j G k,j “+”  p P “+”  Q,1 Q k,1 “+”  i>1  Q,i ψ 0,i  Q k,i } Design effect Effect of Permanent actions Prestress Combined with EN ULS Verification (Persistent and Transient Design Situation) Introduction to EN 1990 – Section 6

19 EUROCODES A tool for building safety and reliability enhancement E d = E {  j≥1  G,j G k,j “+”  p P “+”  Q,1 Q k,1 “+”  i>1  Q,i ψ 0,i  Q k,i } Design effect Effect of Permanent actions Prestress Leading variable action Combined with EN ULS Verification (Persistent and Transient Design Situation) Introduction to EN 1990 – Section 6

20 EUROCODES A tool for building safety and reliability enhancement E d = E {  j≥1  G,j G k,j “+”  p P “+”  Q,1 Q k,1 “+”  i>1  Q,i ψ 0,i  Q k,i } Design effect Effect of Permanent actions Prestress Leading variable action Accompanying variable actions Combined with EN ULS Verification (Persistent and Transient Design Situation) Introduction to EN 1990 – Section 6

21 EUROCODES A tool for building safety and reliability enhancement EN 1990: Table A1.1 - Recommended values of  factors for buildings Introduction to EN 1990 – Section 6

22 EUROCODES A tool for building safety and reliability enhancement EN 1990: Table A1.1 - Recommended values of  factors for road bridges Introduction to EN 1990 – Section 6

23 EUROCODES A tool for building safety and reliability enhancement Expression (6.10) in EN 1990 Expressions (6.10a) and (6.10b) in EN 1990 Ultimate limit states of STR/GEO - Fundamental combination for persistent and transient design situations 0,85    1,00 Introduction to EN 1990 – Section 6

24 EUROCODES A tool for building safety and reliability enhancement Variation of the reliability index for one variable action for EN 1990 Introduction to EN 1990 – Section 6

25 EUROCODES A tool for building safety and reliability enhancement Introduction to EN 1990 – Section 6

26 EUROCODES A tool for building safety and reliability enhancement APPROACH 1 APPROACH 2 APPROACH 3 TABLES A1.2(A) A1.2(B) A1.2(C) ULS EQU ULS STR without geotechnical actions ULS STR with geotechnical actions ULS GEO Introduction to EN 1990 – Section 6

27 EUROCODES A tool for building safety and reliability enhancement Introduction to EN 1990 – Section 6 Safety in geotechnical design

28 EUROCODES A tool for building safety and reliability enhancement Approach 1: Applying in separate calculations design values from Table A1.2(C) and Table A1.2(B) to the geotechnical actions as well as the other actions on/from the structure. In common cases, the sizing of foundations is governed by Table A1.2(C) and the structural resistance is governed by Table A1.2(B) ; NOTE In some cases, application of these tables is more complex, see EN Approach 2 : Applying design values from Table A1.2(B) to the geotechnical actions as well as the other actions on/from the structure ; Approach 3 : Applying design values from Table A1.2(C) to the geotechnical actions and, simultaneously, applying partial factors from Table A1.2(B) to the other actions on/from the structure, NOTE The use of approaches 1, 2 or 3 is chosen in the National annex. Introduction to EN 1990 – Section 6

29 EUROCODES A tool for building safety and reliability enhancement Accidental design situations : expression 6.11b Seismic design situations : expression 6.12b Introduction to EN 1990 – Section 6

30 EUROCODES A tool for building safety and reliability enhancement EN 1990: Design values of actions for use in accidental and seismic combinations of actions for both buildings and bridges Introduction to EN 1990 – Section 6

31 EUROCODES A tool for building safety and reliability enhancement Serviceability limit states It shall be verified that : E d  C d (6.13) where : C d is the limiting design value of the relevant serviceability criterion E d is the design value of the effects of actions specified in the serviceability criterion, determined on the basis of the relevant combination Introduction to EN 1990 – Section 6

32 EUROCODES A tool for building safety and reliability enhancement Serviceability limit states : combinations of actions n For function and damage to structural and non-structural elements (e.g. partition walls etc) the Characteristic Combination (irreversible SLS) should be used Introduction to EN 1990 – Section 6

33 EUROCODES A tool for building safety and reliability enhancement Serviceability limit states : combinations of actions n For comfort to user, use of machinery, avoiding ponding of water etc. the Frequent Combination (reversible SLS) should be used Introduction to EN 1990 – Section 6

34 EUROCODES A tool for building safety and reliability enhancement Serviceability limit states : combinations of actions n For appearance of the structure, the Quasi-permanent Combination (reversible SLS) should be used Introduction to EN 1990 – Section 6

35 EUROCODES A tool for building safety and reliability enhancement w c Precamber in the unloaded structural member w 1 Initial part of the deflection under permanent loads of the relevant combination of actions according to expressions (6.14a) to (6.16b) w 2 Long-term part of the deflection under permanent loads w 3 Additional part of the deflection due to the variable actions of the relevant combination of actions according to expressions (6.14a) to (6.16b) w tot Total deflection as sum of w 1, w 2, w 3 w max Remaining total deflection taking into account the precamber Vertical deflections Introduction to EN 1990 – Section 6

36 EUROCODES A tool for building safety and reliability enhancement Horizontal displacements Introduction to EN 1990 – Section 6

37 EUROCODES A tool for building safety and reliability enhancement Thank you for your attention Introduction to EN 1990 – Section 6