Loads on Braced Excavations in Soft Clay
Publication: International Journal of Geomechanics
Volume 5, Issue 2
Abstract
A parametric finite element study has been carried out to demonstrate the importance of clay strength and depth of clay layer on the earth pressures, strut loads, and bending moments for a strutted sheet pile wall in soft, essentially normally consolidated clay. The clay is modeled as nonlinear and anisotropic. The modeled excavation is deep. For a shear strength profile giving a close to failure condition the maximum bending moment is found to be 6 times larger than for a clay profile with 40% higher strength, and the maximum strut loads are up to twice as large. The maximum strut loads are significantly higher than those given by existing empirical design rules. Comparative analyses with an isotropic linear elastic–plastic soil model show relatively small differences in moments and strut loads. Comparisons against analyses with a beam-on-spring type finite element model show significant differences to the continuum FEM analyses. The main reason is that beam-on-spring models cannot capture the significant effect of arching on earth pressures, strut loads and bending moments.
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Acknowledgments
The writers would like to thank Siren Knudsen for assisting with the SPUNT-A3 analyses, and the Research Council of Norway for funding this work.
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Information & Authors
Information
Published In
International Journal of Geomechanics
Volume 5 • Issue 2 • June 2005
Pages: 107 - 113
Copyright
© 2005 ASCE.
History
Received: Mar 26, 2004
Accepted: Oct 25, 2004
Published online: Jun 1, 2005
Published in print: Jun 2005
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