IIW White Paper

9 Needs and challenges of major industry sectors for future applications

9.9.1 Needs and Challenges Perhaps nothing is more important to improving the quality of life than protecting life itself. During major natural catastrophes, buildings can collapse, resulting in human fatalities that can run into the thousands. Investigations of the ruins frequently reveal the consequences of substandard design or construction practices, regardless of the basic method of construction, whether timber, masonry, concrete or steel. Some buildings are simply not required to be designed in accordance with modern standards and the disastrous performance of structures is predictable, given the nature of the construction standards that are locally accepted. In such situations, the local building codes need to be raised. In other situations, appropriate codes have been adopted but the lack of adherence to the applicable standard is the problem. Such practices may be the result of ignorance of the significance of the requirement. Reports of illegal bribing of oversight officials persist and substandard construction materials are yet another problematic area. Fraudulent substitution of unacceptable materials occurs. A challenge is to emphasise the importance of construction quality and the consequences of non-conformance. When responsible standards are adopted and enforced, quality steel construction will be seen as more economical, and hundreds of lives will be saved in future catastrophic natural events. For many years, steel structures have been the preferred type of structure when the forces of nature attack. Yet many local communities lack the expertise in steel design concepts, or do not have easy access to affordable steel, or lack the workers needed for quality steel construction. Education and training are key challenges in this regard. Since buildings are field erected, much of the welding is performed manually. The size of the structures results in significant variation in fit-up which makes automation difficult. The one-of-a-kind nature of buildings makes each construction site unique, and again precludes easy automation. The challenge is to develop the required technology to make automated and robotic solutions viable under these conditions. Such systems must be robust under field conditions. With respect to concrete construction, welded splices are often made with poor quality. Automated, resistance butt splicing methods have been shown to be inconsistent. Manual and semiautomatic welding methods also result in irregular quality, particularly for direct butt splices. Inspection of such welds is difficult. New or improved welding methods, training and inspection are needed for concrete construction. Seismic loading subjects buildings to extreme loading conditions. Most structures are designed to resist these infrequent but large loads by permitting localised yielding to occur in select locations, typically within the steel members themselves (as opposed to within welded regions). The required material properties of welds and base metals, as well as required weld quality, acceptable weld details and other factors will likely be the subject of ongoing investigations following major earthquakes since laboratory investigations will likely never predict all that damage that post-earthquake investigations will reveal. Blast-resistant design will likely, but unfortunately, be an ongoing topic of interest. Blast-resistant design attempts to preclude disproportional collapse, even in front of considerable structural damage. Acceptable overall structural design, material properties, details, quality levels and expected performances due to different blasts are areas where research still needs to be performed.

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Through Optimum Use and Innovation of Welding and Joining Technologies

Improving Global Quality of Life