ESIS TC12 "Probabilistic Interpretation Of Mechanical Property Data"
TC12 UPDATE 2008
A combined meeting of ESIS Technical Committee 12, named: Probabilistic Analysis of Material Property Data (Chairman Dr R Moskovic), with FESI Workshop was organised by FESI on 5 June 2008 at the Royal Academy of Engineering in London. Approximately 30 people attended. The meeting addressed the issue of understanding quasi-brittle fracture of materials and their behaviour through modelling and probabilistic approaches.
In introducing the meeting the chairman Professor P Flewitt (Magnox Electrical and Bristol University) identified several issues that needed to be addressed. In particular how does quasi-brittle behaviour differ from brittle behaviour which occurs under linear-elastic and elastic-plastic conditions. A number of excellent presentations were given on the behaviour of concrete, graphite and ceramics by Prof. B Karihaloo (Cardiff University), Prof. R Stevens (Bath University),Dr A Hodgkins (Serco), Dr J Marrow (Manchester University), Dr G Neighbour (Hull University) Dr R Moskovic (Magnox Electric) and Prof. J Knott (Birmingham University). Presentations were followed by a discussion led by Prof. J Knott with contributions from, in particular Professors G Williams and D Smith. It was concluded that unlike brittle materials, quasi-brittle materials exhibit tension softening which is characterised by increase in deformation with decreasing tension capacity past the ultimate strength. This is one of the main reasons for the lack of success of LEFM in explaining the behaviour of quasi-brittle materials. Scaling of strength measurements obtained on laboratory sized specimens to structural components is one of the main challenges that need to be resolved for these materials.
In introducing the meeting the chairman Professor P Flewitt (Magnox Electrical and Bristol University) identified several issues that needed to be addressed. In particular how does quasi-brittle behaviour differ from brittle behaviour which occurs under linear-elastic and elastic-plastic conditions. A number of excellent presentations were given on the behaviour of concrete, graphite and ceramics by Prof. B Karihaloo (Cardiff University), Prof. R Stevens (Bath University),Dr A Hodgkins (Serco), Dr J Marrow (Manchester University), Dr G Neighbour (Hull University) Dr R Moskovic (Magnox Electric) and Prof. J Knott (Birmingham University). Presentations were followed by a discussion led by Prof. J Knott with contributions from, in particular Professors G Williams and D Smith. It was concluded that unlike brittle materials, quasi-brittle materials exhibit tension softening which is characterised by increase in deformation with decreasing tension capacity past the ultimate strength. This is one of the main reasons for the lack of success of LEFM in explaining the behaviour of quasi-brittle materials. Scaling of strength measurements obtained on laboratory sized specimens to structural components is one of the main challenges that need to be resolved for these materials.
TC12 UPDATE 2007
The ESIS Technical Committee TC12 is concerned with application of probability and statistical modelling to structural integrity assessments in general, and material property data in particular. To progress the TC12 activities a one day workshop was organised by TC12 in conjunction with the UK Forum for Engineering Structural Integrity (FESI) on 9th june 2006: the topic of the workshop was “Using Probability Modelling in Structural Integrity Assessments”.
The meeting was held in central London at the Royal Academy of Engineering. The workshop opened with a welcome to the 30 delegates pointing out that, in addition to the informed presentations and discussions, it was hoped to identify future topics for inclusion in the forward programme for TC12. A short introduction was given by Professor P E J Flewitt, chairman for the day, setting the background to this important area of probabilistic assessments for both the industrial and business communities across many sectors of transport, power generation, petrochemical, civil structures and aerospace.
A wide range of high quality presentations followed covering modelling of fracture toughness by different statistical techniques which include both the Master Curve approach and statistical analysis. In addition to these, presentations were given on modelling of creep crack growth, fatigue crack growth, evolution of pitting in stress corrosion cracking and use of partial safety factors in fracture mechanics. Each presentation was followed by a lively discussion highlighting the many challenges that remain to achieve broad acceptance and application of probabilistically based structural integrity assessments for structures and components. In the course of the concluding discussion it was recognised that future topics to address would cover the use of computer simulations in modelling and application of probabilistic methods.
The meeting was held in central London at the Royal Academy of Engineering. The workshop opened with a welcome to the 30 delegates pointing out that, in addition to the informed presentations and discussions, it was hoped to identify future topics for inclusion in the forward programme for TC12. A short introduction was given by Professor P E J Flewitt, chairman for the day, setting the background to this important area of probabilistic assessments for both the industrial and business communities across many sectors of transport, power generation, petrochemical, civil structures and aerospace.
A wide range of high quality presentations followed covering modelling of fracture toughness by different statistical techniques which include both the Master Curve approach and statistical analysis. In addition to these, presentations were given on modelling of creep crack growth, fatigue crack growth, evolution of pitting in stress corrosion cracking and use of partial safety factors in fracture mechanics. Each presentation was followed by a lively discussion highlighting the many challenges that remain to achieve broad acceptance and application of probabilistically based structural integrity assessments for structures and components. In the course of the concluding discussion it was recognised that future topics to address would cover the use of computer simulations in modelling and application of probabilistic methods.
TC12 UPDATE 2006
Minutes of TC12 meeting held in London on June
NEXT MEETINGS
TC12 has organised a ESIS TC12 Meeting.
Probability Modelling as Applied in Structural Integrity Assessments
Chaired by Professor Peter EJ Flewitt, Bristol University and British Nuclear Group
Date: 9th June 2006
Venue: Academy of Engineering, London, Great Peter St SW1P 3LW
Nearest underground station: Westminster and St James’s Park
Purpose
To review use of statistical methods for interpretation of materials property data design of experiments and use probabilistic methods in structural integrity assessments.