1 / 29

Taskforce Meeting Zurich 6./7.09.2004

Taskforce Meeting Zurich 6./7.09.2004. Summary and Progress Jochen Köhler, ETH Zurich, Switzerland. Contents. Stress Strain Relation Serviceability DOL GLULAM Connections Quantification of model parameters. Stress Strain Relation. According to Glos (1978). Stress Strain Relation.

alaire
Download Presentation

Taskforce Meeting Zurich 6./7.09.2004

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Taskforce Meeting Zurich 6./7.09.2004 Summary and Progress Jochen Köhler, ETH Zurich, Switzerland

  2. Contents • Stress Strain Relation • Serviceability • DOL • GLULAM • Connections • Quantification of model parameters

  3. Stress Strain Relation • According to Glos (1978)

  4. Stress Strain Relation • According to Glos (1978)

  5. Stress Strain Relation • According to Glos (1978) Conditions:

  6. Stress Strain Relation • According to Glos (1978) Conditions:

  7. Stress Strain Relation • According to Glos (1978) Discussion: MOE in tension = MOE compression ? Quantification of asymptotic compression strength and strain. Modelling of N ? Typical values:

  8. Stress Strain Relation Actions: • Quantify asymptotic stress • Include into the Model Code Coordination: Jochen Köhler

  9. Serviceability • According to Torratti (1992): The following conditions apply • The deformations are calculated in the grain direction only • The maximum stress bending stress is 20 Mpa • Natural conditions environment conditions apply (temperature and humidity) • The model has been successfully compared to tests on European softwoods, both solid wood and glulam of different sizes

  10. Serviceability

  11. Serviceability Actions: • Producing a matrix for different load and climate situations. Therefore the following is needed: • quantify moisture loads (Lars-Oluf Nielsson (Lund)/study from DTU 2003) • quantify load sequences • acquiring data, quantify model parameters • doing calculations and sensitivity analysis Coordination: Tomi Toratti

  12. DOL Limit state function: Model (Nielsen): Applied stress: combined with climate deviations

  13. DOL Limit state function: Model (Barrett): Applied stress: combined with climate deviations

  14. DOL Gaps: • DOL - Tension perpendicular to the grain • DOL - Connections

  15. DOL Actions: • Acquire North American data • Review data, quantify model parameters • Distribute tasks according ‘Tension perpendicular to the grain’ and ‘Connections’ Coordination: John D. Sorensen

  16. GLULAM • Glued laminated timber in BENDING • Load carring capacity depending on the outermost lamination • Lamination = timber boards with length a; jointed by finger joints • a is assumed to be Poisson distributed • The tensile strength and stiffness of each board is assumed to be constant and lognormal distributed. • The strength of the finger joints is assumed to be lognormal distributed

  17. GLULAM Standard deviations?

  18. GLULAM Actions: • Proposal of a simple model • Test data acquisition Coordination: Hans-J. Larsen

  19. Connections Probabilistic Framework: • Johansen equations • “Splitting Mode parallel” • “Splitting Mode perpendicular”

  20. Connections Probabilistic Framework: • Johansen equations

  21. Connections Probabilistic Framework: • Johansen equations

  22. Connections Probabilistic Framework: • “Splitting Mode parallel”

  23. Connections Mixed Mode Fracture Energy

  24. Connections Probabilistic Framework: • “Splitting Mode perpendicular”

  25. Connections Probabilistic Framework: • Effective number of fasteners

  26. Connections Actions: • Acquire test data • Case study – reliability analysis Coordination: André Jorissen

  27. Quantification of Model Parameters

  28. Quantification of Model Parameters Actions: • Collecting Data for a Data Base Coordination:

  29. Summary

More Related