Defining The Problem: Deficiencies Of Design Loads

This paper presents a series of premises. First, it is asserted that modern society is unsustainable and requires fundamental change to make it more so. Since engineering design practice has a considerable impact on society, it also must be transformed. Such a transformation requires a greater contextual awareness of both society and the consequences of engineering actions on it. However, before current practices can be improved, a critique of traditional design practice must first be undertaken. Historically, engineers have made various simplifying assumptions that convert complex problems into simpler ones. In particular, messy and difficult-to-evaluate objectives are often replaced by “design loads.” The ’ design load concept is attractive to engineers for it implicitly substitutes technical objectives for more comprehensive economic and social goals. Yet, examples from civil engineering highlight how the design load concept often distorts or misrepresents even traditional objectives. Several recurring problems emerge from these examples and a partial catalogue is presented. The conclusion is that even traditional engineering practices require better knowledge, not only of system behaviour, but also of the design process itself. Thus, it is reasoned that the quest for a more sustainable society requires an analogous, but even more strenuous, extension of design methods. It is only through facing these challenges that complex environmental and social problems can be met. Modern society is unsustainable. Pollution of air and water, species extinction, habitat destruction, resource depletion, climate change-these are but symptoms of humankind’s long-term impact on Earth’s life-support systems. In addition, the complex human challenges of population growth, greed, disease, poverty, conflict, hunger, dislocation, injustice, and persecution will inevitably take a further toll on Earth’s resources. Thus, if society is to become more sustainable-i.e., better prepared to cope with the long-term impact of human actions-profound changes are required. It is easy to develop guidelines that encourage greater sustainability. A common example is the “three R’s of the environment”-to reduce waste production and dependence on natural resources, to reuse materials wherever possible, and to recycle those products that cannot be reused. Yet it is often difficult to translate these principles into action at all levels. For example, construction materials should be designed and selected for their entire life-cycle, not simply recycled as an after-thought. Decision makers should anticipate and