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BALLOON + JET ENGINE

BALLOON + JET ENGINE. = QUALITATIVELY NEW TRANSPORTATION MEAN ???????. NO !. PARTIAL FACTORS METHOD + COMPUTERS. such as EC or LRFD. = QUALITATIVELY NEW STRUCTURAL RELIABILITY ASSESSMENT CONCEPT ?????. COMPUTERS. NO !. PROBABILISTIC METHOD

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BALLOON + JET ENGINE

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  1. BALLOON + JET ENGINE = QUALITATIVELY NEW TRANSPORTATION MEAN ??????? NO !

  2. PARTIAL FACTORS METHOD +COMPUTERS such as EC or LRFD = QUALITATIVELY NEW STRUCTURAL RELIABILITY ASSESSMENT CONCEPT ????? COMPUTERS NO !

  3. PROBABILISTIC METHOD (such as SBRA) +COMPUTERS = QUALITATIVELY NEW STRUCTURAL 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. R – S = 0 Pf = Σ/ Σ< Pd

  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 Short Dead Wind Long

  8. Two - and More -Component Load Duration Curves Wind Rosette Wind Directon and Wind Velocity

  9. One-component Load Effect Combination Analysis using Monte Carlo technique and ResCom computer program

  10. Probability of Failure Pf 0.001 EC3 LRFD 0.0001 0.00001 SBRA 0.000001 estimate

  11. SBRA Dead + Long-Lasting Dead +Short-Lasting

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

  13. x - x N, Mx, My Combination of multi-component load effects Each Load Effect is expressed, for example, by N, Mx and My

  14. R Resistance R S Load Effect Combination S R - S = 0

  15. Definition of the Resistance P „Reference Level“ ??? USEABILITY 

  16. Reference levels a) Onset of yielding b) Tolerable permanent deflection USEFULLNESS d) Formation of the full plastic hinge c) Limited Damage Non-tolerable permanent deflection

  17. Probability of Failure

  18. Yield stress Ffy Cross-section area F Avar Initial eccentricity Feo Effect of residual stresses FResvar Column Resistance: Variables Variabilities of yield stress, cross-section area, initial eccentricity and effect of residual stresses are expressed by bounded histograms:

  19. Stress (N.mm-2) Slenderness ratio Variables: fy, eo, A, ..

  20. Target Probability Pdaccording to CSN 73 1401-1998

  21. Safety Assessment Using the Probabilistic Simulation-Based Reliability Assessment Concept 1

  22. Target Probability Pdaccording to CSN 73 1401-1998

  23. Steel beam exposed to a combination of loads Load Duration Curves and corresponding Histograms

  24. Dimensioning of a Beam

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

  26. Bar exposed to Tension and Compression

  27. Frame containing leaning columns

  28. Serviceability Assessment Using the Probabilistic Simulation-Based Reliability Assessment Concept 1

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

  30. Target Probability Pdaccording to CSN 73 1401-1998

  31. Steel beam exposed to a combination of loads Load Duration Curves and corresponding Histograms

  32. Serviceability Assessment of a steel beam Application of a ‘blurred’ serviceability limiting value

  33. EXAMPLE 2 Frame containing leaning columns SF= DELtol - DEL( DELtol = 30 mm ) DEL Serviceability assessment Pf = 0.037 < Pd= 0.070 O.K.

  34. Durability Assessment Using the Probabilistic Simulation-Based Reliability Assessment Concept 1

  35. Hypercomputers andmore PENTIUM PC XT 1 MIPS 5  102 MIPS > 10 GIPS

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

  37. SUMMARY AND CONCLUSIONS • 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‘

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