Benefits of pre-loading temporary props for braced excavations
Journal Title: Geotechnical Research - Year 2017, Vol 4, Issue 3
Abstract
Using soil profiles typical of excavations in London, UK and Dubai, UAE calculations have been carried out to compare the performance of temporary steel and proprietary hydraulic propping. Numerical modelling indicates that pre-loading allows the lower-stiffness hydraulic prop to match the performance (in terms of prop load and wall displacement) of a higher-stiffness steel prop, without pre-load. The low prop stiffness also helps to mitigate loading induced by thermal effects. Furthermore, where limiting the horizontal deflection of the wall is critical, the application of a calibrated pre-load can improve the economy of the temporary works by reducing the prop size. Pre-loaded props are sometimes associated with increased bending moment and shear force values in the retaining wall. The finite-element models produced for this paper prove that for the cases considered, the use of pre-loaded low-stiffness hydraulic props achieved the same performance as stiff steel props, with no impact on the wall’s reinforcement. Further work is suggested to explore how manipulating and varying the pre-loading values in multipropped basements might be used to improve further the performance and/or the economy of the retaining wall and how this might affect the load transfer from temporary to permanent supports in the longer term.
Authors and Affiliations
Beniot Latapie
Keywords
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- EP ID EP292357
- DOI 10.1680/jgere.17.00011
- Views 55
- Downloads 0
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