Abstract. Structures such as roof trusses will not suddenly collapse without ample warning such as significant deflection, tilting etc. if the designer manages to avoid the cause of structural failure at the material level and the structural level. This paper outlines some principles and procedures of PDCA circle and QC tools which can show some clues of structural problems in terms of material or structural performance

Abstract. The purpose of this paper is to evaluate the effect of size or dimension changes of reinforced concrete structures, in terms of structural performance and serviceability limit states. A theoretical and design study was carried out to evaluate the structural performance and serviceability of reinforced concrete structures using the European Code of Practice (EC2) and British Code of Practice (BS8110). The analysis required nine different sizes of reinforced concrete beams, with dimension between 150mm x 250mm and 350mm x 250mm. The study showed that dimension changes significantly affected the load-carrying capacity and deflection of reinforced concrete members; regardless of their depth/width ratio. The analysis results also produced an equation (presented here) to assess the performance of reinforced concrete members, based on the codes of practice.