Measurement and analysis of temporary prop loads at Canary Wharf underground station, east London

Abstract

The loads developed in tubular steel temporary props during the construction of the London Underground Jubilee Line Extension station at Canary Wharf were monitored using vibrating wire strain gauges. Prop temperatures were also measured to investigate the fluctuation of load with temperature. In this paper, the measured prop loads are related to temperature, the excavation process and certain construction details. They are then compared with the loads calculated using modified limit equilibrium calculations and a series of parametric finite-element analyses. Prop loads reasonably close to those measured can be calculated using either technique, but certain discrepancies between the two calculations in terms of the detail of the earth pressure distributions acting on the wall require further research.