Knowledge-based systems for the demolition industry

The demolition industry has been examined as a domain for knowledge-based systems, through two very different research investigations, both involving commercial companies. A small local demolition company has collaborated with an investigation into the use of knowledge-based systems to assist with, and model, the process of estimating arisings from demolition work. The majority of UK demolition companies do not have the resources or expertise to approach the quantity estimating task in the same way as the rest of the construction industry. The demolition estimator uses his expertise to arrive at quantity estimates that are as accurate as possible but are made in as short a time as possible, without requiring detailed measurements to be made. The research proposes a model of the reasoning processes that a demolition estimator has been observed to carry out on site. The model forms the basis of a reasoning strategy that ensures that the most accurate estimate is obtained from the available data. Missing data is handled by further inferencing, reference to a structure model, or a shift in the level of reasoning. A prototype knowledge-based system has been developed to estimate the mass of steel in a roof truss system, based upon this proposed model. The system has been developed on a PC using the Crystal shell. The above investigation identified the area of safety in demolition work as being suitable for further examination of the application of knowledge-based systems techniques. This examination was carried out in collaboration with a leading national demolition contractor, based in Rotherham. The demolition safety advisor research project involved the integration of knowledge about safe demolition practice from an expert Demolition Engineer, and from legislative and advisory documents. The methods, difficulties, and implications of this integration are described. Explanation facilities are discussed which combine a variety of information formats, including video and hypertext. A reasoning strategy is suggested which allows a suitable demolition method to be established, and which allows safety advice to be given regarding demolition operations and structure features. A prototype system has been developed on a Sun Workstation, which gives safety advice concerning the explosive demolition of brick chimneys, and reinforced concrete framed structures such as blocks of flats.