This paper applies a novel structural optimisation method to three case studies: a simple portal frame used to illustrate how the method works, a large warehouse and a 60-storey building. The method is based on the principle of virtual work and is called the Virtual Work Optimisation (VWO) method. The VWO method selects member sizes in an automated way to meet strength and deflection design criteria. An optimal structure is defined as one that satisfies all design constraints using the minimum amount of material. The warehouse example was chosen for comparison purposes as it was designed by a company of professional engineers. The VWO method designed the warehouse in less than 2 minutes and produced a 3.5% saving on the engineers’ solution. The 60-storey building was optimised in 189 iterations to produce a structure satisfying 60 deflection constraints and strength requirements for 1080 members. The VWO system is significantly faster than other optimisation methods reported in the literature. R. Walls, BSc (Eng) Research assistant, School of Civil & Environmental Engineering, University of the Witwatersrand Prof. A. Elvin, PhD, SM, BSc(Eng) Associate Professor, School of Civil & Environmental Engineering, University of the Witwatersrand
At the start of the 21st century, humanity is faced with a global challenge of unprecedented scale: Climate change, a synonym for rising global temperatures and water levels and the promise of extreme weather events. Add to this an increased demand on food, water and energy and you get what Professor Beddington, chief scientific adviser to HM Government, calls 'a perfect storm of events' (Beddington 2009). Clement Thirion, MEng, MSc
This paper looks at the use of Interlocking Stabilised Soil Block (ISSB) technology in the less economically developed world, particularly focusing on the current work in Uganda. The paper takes the reader through the history behind ISSB technology and how advancements in equipment as well as an increased nongovernmental organisation (NGO) presence in recent years have allowed the technology to be much more widely used in local communities. Central to this paper is a critical look at the advantages of ISSBs over fired bricks. It looks at several projects which have employed ISSB technology and how environmentally friendly technology can be made available to rural communities while still meeting rigorous building standards. The paper tries to highlight not just the economic or the technological advances, but also the positive environmental and socio-economic benefits of using ISSB technology. Ewan Smith, MEng, CEng, MIED