Taskforce Meeting Zurich 6./7.09.2004

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Taskforce Meeting Zurich 6./7.09.2004

• Summary and Progress
• Jochen Köhler, ETH Zurich, Switzerland

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Contents

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

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Stress Strain Relation

• According to Glos (1978)

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Stress Strain Relation

• According to Glos (1978)

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Stress Strain Relation

• According to Glos (1978)

Conditions
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Stress Strain Relation

• According to Glos (1978)

Conditions
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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


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Stress Strain Relation

• Actions
• Quantify asymptotic stress
• Include into the Model Code
• Coordination
• Jochen Köhler

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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

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Serviceability
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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

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DOL
Limit state function Model (Nielsen)
Applied stress
combined with climate deviations
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DOL
Limit state function Model (Barrett)
Applied stress
combined with climate deviations
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DOL

• Gaps
• DOL - Tension perpendicular to the grain
• DOL - Connections

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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

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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

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GLULAM
Standard deviations?
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GLULAM

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

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Connections

• Probabilistic Framework
• Johansen equations
• Splitting Mode parallel
• Splitting Mode perpendicular

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Connections

• Probabilistic Framework
• Johansen equations

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Connections

• Probabilistic Framework
• Johansen equations

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Connections

• Probabilistic Framework
• Splitting Mode parallel

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Connections

• Mixed Mode Fracture Energy

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Connections

• Probabilistic Framework
• Splitting Mode perpendicular

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Connections

• Probabilistic Framework
• Effective number of fasteners

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Connections

• Actions
• Acquire test data
• Case study reliability analysis
• Coordination André Jorissen

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Quantification of Model Parameters
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Quantification of Model Parameters

• Actions
• Collecting Data for a Data Base
• Coordination

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Summary
Topic Coordination
Stress Strain Relation, Basic Material Properties - Tension Perpendicular - Grading Jochen Köhler ?? ??
Serviceability Tomi Toratti
GLULAM Hans-J. Larsen
DOL Connections John Sorensen ??
Connections André Jorissen
Data Base ??
Moisture ??