BALLOON +JET ENGINE

= QUALITATIVELY NEW TRANSPORTATION

MEAN ???????

NO !

PARTIAL FACTORSMETHOD

+ COMPUTERS

= QUALITATIVELY NEW STRUCTURAL RELIABILITY ASSESSMENT CONCEPT ????? NO !

such as ECor LRFD

COMPUTERS

PROBABILISTICMETHOD(such as SBRA)

+ COMPUTERS

=

QUALITATIVELY NEWSTRUCTURAL RELIABILITY ASSESSMENT CONCEPT ??? YES!

4

SBRA•Input variables are expressed by bounded non-parametric

histograms.•Reliability function is analyzed

by the designer using Monte Carlo method.

•Reliability is expressed by Pf < Pd, where Pf is the

probability of failure and Pd is the target probability given in

codes.

Pf = Σ / Σ < Pd

R – S = 0

5

Computer Program AntHill for Windows

6

What is the Load Duration Curve (LDC)?

Loading History ‚Sorted‘ History

LDC

7

Load Duration Curves, LDC,and corresponding Histograms

Dead Short

Long

Wind

8

Two - and More -Component Load Duration Curves

Wind Rosette

Wind Directonand

Wind Velocity

9

One-component Load Effect Combination Analysis using Monte Carlo technique and

ResCom computer program

10

Loading combination1. 2. 3. 4. 5. 6.

D 100 85 70 55 40 25

LL 15 15 15 15 15

SL 15 15 15 15

SN 15 15 15

W 15 15

E 15Lo

ad

Cha

ract

eris

tic

Mag

nitu

des

[kN

]

Set A

60,00

70,00

80,00

90,00

100,00

110,00

120,00

130,00

140,00

150,00

1. 2. 3. 4. 5. 6.

Loading combination no.

Lo

ad

[k

N]

ma

xim

um

0,999

0,995

0,990

LRFD

CAN

EUR

DIN -10,00

0,00

10,00

20,00

30,00

40,00

50,00

60,00

70,00

80,00

90,00

100,00

110,00

1. 2. 3. 4. 5. 6.

Loading combination no.

Lo

ad

[k

N]

min

imu

m

0,999

0,995

0,990

LRFD

CAN

EUR

DIN

11

Loading combination7. 8. 9. 10.

D 70 55 40 25

LL 30 45 60 75

SL

SN

W

ELo

ad

Cha

ract

eris

tic

Mag

nitu

des

[kN

]

Set B

120,00

125,00

130,00

135,00

140,00

145,00

150,00

155,00

160,00

7. 8. 9. 10.Loading combination no.

Lo

ad

[k

N]

ma

xim

um

0,999

0,995

0,990

LRFD

CAN

EUR

DIN

20,00

25,00

30,00

35,00

40,00

45,00

50,00

55,00

60,00

65,00

70,00

7. 8. 9. 10.

Loading combination no.

Lo

ad

[k

N]

min

imu

m

0,999

0,995

0,990

LRFD

CAN

EUR

DIN

12

Loading combination34. 35. 36. 37. 38.

D 15 15 15 15 15

LL

SL

SN 15 30 45 60 75

W 70 55 40 25 10

ELo

ad

Cha

ract

eris

tic

Mag

nitu

des

[kN

]

Set H

40,00

50,00

60,00

70,00

80,00

90,00

100,00

110,00

120,00

130,00

140,00

150,00

34. 35. 36. 37. 38.Loading combination no.

Lo

ad

[k

N]

ma

xim

um

0,999

0,995

0,990

LRFD

CAN

EUR

DIN

-100,00

-90,00

-80,00

-70,00

-60,00

-50,00

-40,00

-30,00

-20,00

-10,00

0,00

10,00

34. 35. 36. 37. 38.

Loading combination no.

Lo

ad

[k

N]

min

imu

m

0,999

0,995

0,990

LRFD

CAN

EUR

DIN

Probability of Failure Pf

0 ,000001

0 ,00001

0 ,0001

0 ,001

1 6 11 16 21 26

Kom binace zatížen í (...)

Pf

EC3 LRFD Odhad EC3 SBRA Odhad SBRA

stá lé a 1 nahod iléza tížení

s tá lé a 2 nahod iléza tížení

s tá lé a 3 nahod iléza tížení

s tá lé a 4 nahod iléza tížení

s tá lé a 5 nah.

za t.

s tá lé a 6 nah.

za t.

LRFD

SBRA

EC30.001

0.0001

0.00001

0.000001estimate

14

Loads combination curves (G+Q)

0,8

0,9

1

1,1

1,2

1,3

1,4

1,5

1,6

0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1

Qk/(Qk+Gk)

glo

ba

l s

afe

ty c

oe

ffic

ien

t

equ. 6.10

equ. 6.10a (VQ=20%)

equ. 6.10b (VQ=70%)

equ. 6.10b

15

LOADS COMBINATION CURVES

1,20

1,25

1,30

1,35

1,40

1,45

1,50

1,55

0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1

Qk/(Qk+Gk)

Ga

ma

(G+

Q)

VG=0,05 & VQ=0,2

VG=0,05 & VQ=0,7

VG=0,10 & VQ=0,7

VG =0,10 & VQ=0,2"

equ. 6.10

equ. 6.10bequ. 6.10a

equ. 6.10a amended

Formula are established w ith0,7 and 0,85

16

Long+D

1,25

1,30

1,35

1,40

1,45

1,50

1,55

0,00 0,20 0,40 0,60 0,80 1,00 1,20

0.9999

0.9995

0.9990

Short+D

1,20

1,25

1,30

1,35

1,40

1,45

1,50

1,55

0,00 0,20 0,40 0,60 0,80 1,00 1,20

0.9999

0.9995

0.9990

SBRA

Dead + Long-Lasting

Dead +Short-Lasting

17

(c)

D

L 1

S N

W X

S

L 2

W Z

30°

60°

60°

60°

W X

D

L 1

S N

W X

1 2

34

y

z

D

L 1

S N

S L 2

W Z

30°

60°

1 2

34

y

z

1 2

34

y

z

(a ) (b)

x x

x

y

z

b=

4mS

b=

4m

L2

a 6,928mS

c,3

09m

S

a ,309mL2

c,3

09m

L2

(a) N (b) N, Mx (c) N , Mx , My

18

Combination of multi-

component load effects

Each Load Effect is expressed, for example,

by N, Mx and My

x - x

N, Mx, My

19

S

Load Effect

Combination S

R - S = 0

Resistance R

R

20

Definition of the ResistanceP

„Reference Level“ ???

USEABILITY

21

Reference levels

a) Onset of yielding

b) Tolerable permanent deflection

Non-tolerable permanent deflection

d) Formation of the full plastic hinge

USEFULLNESS

c) Limited Damage

22

Probability of Failure CASE

Reference level defined by

Steel beam Probability of Failure

(a)

Onset of yielding Elastic range 0.000293

< Pd

(b)

Tolerable permanent deformation

Acceptable permanent deformation

0.000044

< Pd

(c ) Tolerable Damage To be repaired or replaced

0.000015

< Pperf

(d) Collapse Disposal 0.000008

< ????

Variabilities of yield stress, cross-section area, initial eccentricity and effect of residual stresses are expressed by bounded histograms:

Cross-section area Avar

Initial eccentricity eo Effect of residual stresses Resvar

Yield stress fy

Column Resistance: Variables

24

Slenderness ratio

Str

ess

(N.m

m-2)

Variables:fy, eo, A, ..

25

Target Probability Pd

according to CSN 73 1401-1998Importance

of theStructure

CarryingCapacity

Pd

Service-Ability

Pd

LessImportant

0,000 5 0,16

CommonStructures

0,000 07 0,07

VeryImportant

0,000 008 0,023

26

SafetyAssessment

Using the Probabilistic Simulation-Based

Reliability Assessment Concept

1

27

Target Probability Pd

according to CSN 73 1401-1998Importance

of theStructure

CarryingCapacity

Pd

Service-Ability

Pd

LessImportant

0,000 5 0,16

CommonStructures

0,000 07 0,07

VeryImportant

0,000 008 0,023

28

Steel beam exposed to a combination of loads

Load Duration Curves and corresponding Histograms

29

Dimensioning of a Beam

30

Safety check of the steel beam(Pf,saf = 0,00003 < Pd,saf = 0,00007)

31

Bar exposed to Tension and Compression

32

Frame containing leaning columns

33

Serviceability Assessment

Using the Probabilistic Simulation-Based

Reliability Assessment Concept

1

34

STRUCTURAL SERVICEABILITY: A CRITICAL APPRAISAL AND RESEARCH NEEDS

By the Ad Hoc Committee on Serviceability Research, Committee on Research of the Structural Division

ABSTRACT: Serviceability limit states in building structures are conditions inwhich the functions of the building are disrupted during normal use by excessivedeformation, motion, or deterioration. As standards evolve toward probability-based limitstates design methods, serviceability issues are expected to become an increasinglyimportant design consideration.

This paper is part of the Journal of Structural Engineering, Vol. 112, No. 12, December, 1986©ASCE, ISSN 0733-9445/86/0012-2646/$01.00. Paper No. 21106.

Design Loads and Load CombinationsConsistent probability-based loads and load combinations should be developed forchecking applicable serviceability limit states.

Structural Load ModelingSimple load models that can be used for analyzing creep, differential settlement, and crackingshould be developed.

35

Basic alternatives of serviceability reliability conditions (Cases 1 to 25)

36

Target Probability Pd

according to CSN 73 1401-1998Importance

of theStructure

CarryingCapacity

Pd

Service-Ability

Pd

LessImportant

0,000 5 0,16

CommonStructures

0,000 07 0,07

VeryImportant

0,000 008 0,023

37

Steel beam exposed to a combination of loads

Load Duration Curves and corresponding Histograms

38

Serviceability Assessment of a steel beam

Application of a ‘blurred’ serviceability limiting value

39

Frame containing leaning columns

SF= DELtol - DEL ( DELtol = 30 mm )

Serviceability assessment Pf = 0.037 < Pd = 0.070 O.K.

DEL

EXAMPLE 2

40

DurabilityAssessment

Using the Probabilistic Simulation-Based

Reliability Assessment Concept

1

41

R , S

00

0

P , P

0

P

P

T

T

SL

SL

Time

Time

P Pf

f

fd

d d

(a)

R , S

00

0

P , P

0

PT

T

SL

SL

Time

Time

P Pf

ff

d

d

d

(b)

R

S (t)

R , S

00

0

P , P

0

P

P

T

T

SL

SL

Time

Time

P Pf

ff

d

d

d

(c)

R (t)

S (t)

R , S

00

0

P , P

0

P

P

T

T

SL

SL

Time

Time

P Pf

f

f d

d

d

(d)

SF = (R (t) - S (t))

SF = (R - S (t))

SF = (R - S )

S F = (R (t) - S )

R

S

R (t)

S

42

SBRA – From Components to Systems

1989 1999 2009 (?)

1 MIPS 5 102 MIPS > 10 GIPS

PC XT PENTIUM Hypercomputersand more

43

How will look like the new generation of specifications and design tools?

44

• Impact of computer technology • Reengineering of the design procedure• Application of powerful simulation techniques in

designer‘s work• From Components to Systems• New generation of specifications, application of

databases and information technology

• Education of designers: From deterministic to probabilistic ‘way of thinking‘

SUMMARY AND CONCLUSIONSSUMMARY AND CONCLUSIONS