The degradation of products and structures imposes a significant cost for the owners and operators of plant and equipment. Besides the financial aspects, the possible risk to human life and health is always a major consideration.

In service only a few structures experience purely static loads and most will be subjected to some fluctuations in applied stresses and may therefore be regarded as being fatigue loaded.

Besides corrosion and brittle fracture, fatigue is the main source (more than 75%) of failures or degradation of steel structures. Fatigue failures can occur in both welded and unwelded component.

However, most of the steel products are fabricated using welding and welded joints are most vulnerable to fatigue.

To avoid premature failures and high maintenance costs, design procedures should be based on state of the art technical standards and guidelines.

The seminar will cover a range of fatigue assessment techniques focusing on a widely used assessment based on a nominal stress method as used in AS/NZS 5100.6, NZS 3404.1 and AS 4100 as well as IIW Guideline “Fatigue design of welded structures”. Work examples to demonstrate the application of the assessment methodology will be demonstrated.

Steel structures can also suffer usually suffer from brittle fracture e.g. as a result of fatigue damage. Brittle fracture is a sudden event which only can be avoided by proper design and selection of material. The seminar will cover design to avoid brittle fracture with the reference to HERA guideline that is currently being develop. It extends the range of steels and temperatures supplementing brittle fracture requirements of NZS 3404.1 and AS/NZS 5100.6.