The seminars took place in Hamilton, Auckland, Wellington, Christchurch and Queenstown in July/August.
Around 120 professionals attended the events, a record high for this series! Welded connections are subject to high levels of loadings in bridges and buildings in seismic zones, as well as in construction equipment, machinery etc.
Achieving satisfactory performance in welded joints involves the appropriate joint design, selection and verification of materials, proper fabrication, inspection and quality assurance. The designers, engineers and fabricators responsible for the integrity of the product or structure must consider a variety of issues, often involving topics that receive little or no coverage in typical engineering education or training.
This seminar provided an overview of the theory of design of welded steel structures and components with plenty of hands-on guidance for structural and mechanical design engineers.
The morning and late afternoon sessions of the seminar presented by Prof. Adolf Hobbacher, one of the world’s leading experts on weld design issues.
He discussed general aspects of the design of welded joints focussing at fatigue design issues. A concept of fatigue verification by equivalent stress range at 2 million cycles was explained alongside with the verification procedures in terms of stress and number of cycles.
Prof. Hobbacher also introduced a fatigue design procedure of a revised bridge design standard DR AS/NZS 5100.6, Section 13. The new verification approach is based on damage equivalent lambda factors that are selected for individual loading models and other parameters.
The procedure greatly simplifies fatigue assessment as it avoids time consuming damage calculation. The background for the assessment is explained in the seminar notes and the joint publication Hobbacher, Hicks, Karpenko et.al.
The afternoon session covered reliability aspects of steel structures, execution and quality management aspects. It was presented by Dr Stephen Hicks and Dr Michail Karpenko, HERA. To ensure the design assumptions remain valid, the designer needs to specify execution requirements for steel structures.
These requirements are given in a new Standard AS/NZS 5131 Fabrication and Erection of Steel. It introduces the fundamental concept of ‘construction category’ (CC), which is linked to the Importance level of the structure and provides the minimum levels of workmanship required.