Abstract
The evaluation of strut forces is critical to ensure the system stability of braced excavation in urban areas. The most common empirical approach to determine the forces in the struts is the empirical apparent pressure diagram (APD) method. Although the importance of soft clay anisotropy on the stability of excavation systems has been demonstrated by various researchers, there are only limited studies on the influence of anisotropy of soft clay on the forces in the struts. In this paper, extensive plane strain finite element studies have been carried out to analyze the strut forces and the apparent earth pressures for braced excavations in anisotropic clay deposits. The NGI-ADP soil constitutive model was adopted in the finite element analyses to assess the influence of various soil properties and wall stiffness properties on the strut forces. Based on the numerical results, modified design pressure envelopes which consider the anisotropic behavior of clays are proposed for flexible and stiff walls.
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Acknowledgements
This work was supported by National Natural Science Foundation of China (No. 52078086), Program of Distinguished Young Scholars, Natural Science Foundation of Chongqing, China (cstc2020jcyj-jq0087) and the Fundamental Research Funds for the Central Universities (Grant ID 2019CDJDTM0007).
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Zhang, R., Goh, A.T.C., Li, Y. et al. Assessment of apparent earth pressure for braced excavations in anisotropic clay. Acta Geotech. 16, 1615–1626 (2021). https://doi.org/10.1007/s11440-020-01129-x
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DOI: https://doi.org/10.1007/s11440-020-01129-x