Evaluation of digital photogrammetry and 3D CAD modelling applications in construction management

The objective of the paper is to report ongoing research work aimed at developing computer based model that will enable the semi-automatic measurement of construction work in progress. CAD programs are increasingly being used to produce more realistic 3D models of the designed buildings, long before the start of construction on site. These 3D models are usually applied for presentation and visualisation purposes. However, there is greater potential for making use of these 3D CAD models for the development of an automated data capture system. A great deal of time is spent to collect information from the site using conventional measurement techniques. These measurements help project managers to calculate interim payments, monitor progress, analyse productivity and undertake Earned Value Analyses. Recent developments in digital photography and computerised photogrammetry techniques will make it possible to acquire, record and process construction information more rapidly. This paper discusses the potential application of such system and presents a conceptual framework for semi-automated progress measurement system. The paper then outlines the development of the methodology to be used for the automatic comparison of the "data acquired from site" and "data from the existing design documents".