Prop loads in large braced excavations

Embedded walls retaining the sides of large excavations are often supported by temporary props at one or more levels to reduce wall and ground movements. The provision of temporary props during the construction process is costly in both money and time, and there may be risk to the site operatives installing and removing them. This publication presents the findings of an EPSRC and industry-funded research project that measured and analysed the loads in the temporary props at the Canada Water and Canary Wharf station excavations. There is a widely held view within the construction industry that the procedures currently used in design tend to overestimate actual prop loads. The main aim of the research was to investigate the reasons for this apparent discrepancy by monitoring the temporary prop loads. This publication, which accompanies CIRIA C17, will help temporary works designers and geotechnical engineers.