Full-scale proof load test of ultralite cold-formed steel roof truss

Cold-formed steel lipped channel sections are widely used as secondary structural elements in building construction because of its low weight and ease of handling and use. However, these sections are frequently misconceived as having low member stiffness and poor clear spanning ability. An innovative example of how such sections can be used to form the primary roof structures for a factory building located in western part of Singapore is presented in this paper. The roof trusses are designed to span a clear distance of 12m in both directions. The structural roof layout consists of secondary trusses spaced at 4m centres with a clear span of 12m. After the building was completed and fully cladded, a full-scale proof load test of the cold-formed roof trusses was carried out. The test objectives, methods, observations and analysis of the load test are discussed in details and the results show convincingly that such Ultralite cold-formed steel roof trusses can be used without any problem.