Basal Heave Stability of Braced Excavations Considering Spatial Variability in Cement-Admixed Soil Slab
Publication: IFCEE 2024
ABSTRACT
This paper discusses the effect of spatial variability in strength properties of the cement-admixed soil slab on the basal heave stability for braced excavations. Deterministic and random finite element analyses are performed in Optum G2 software. In deterministic analysis, the effect of different strengths and thickness of slab on the basal heave stability are studied. For studying the effect of spatial variability in cement-admixed soil slab, the spatially correlated random fields of undrained shear strength (cuj) are simulated for varying coefficient of variation (COV) and scale of fluctuation (SOF). Results show that the mean value of the FoS decreases with the increase in COV. The mean value of FoS also tends to decrease as the value of SOF increases from 0.5 to 1.0. Finally, equivalent design strengths are computed for the varying spatial parameters to take in account of the spatial variability in strength properties of the cement-admixed soil slab.
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REFERENCES
Bruce, D. A. (2000). “An introduction to the deep soil mixing methods as used in geotechnical applications.”, US Department of Transportation, Federal Highway Administration.
BSI. (2004). BS EN 1997-1:2004: Eurocode 7 – Geotechnical design – part 1: general rules. London, UK: BSI.
Comodromos, E. A., Papadopoulou, M. C., and Georgiadis, K. (2018). “Design procedure for the modelling of jet-grout column slabs supporting deep excavations.” Computers and Geotechnics, 100(2018), 110–120.
Chew, S. H., Kamruzzaman, A. H. M., and Lee, F. H. (2004). “Physicochemical and Engineering behaviour of cement treated clays.” Journal of Geotechnical and Geoenvironmental Engineering, ASCE, 696–705.
Essler, R., and Yoshida, H. (2004). In: M. P. Moseley, K. Kirsch (Eds.), Ground Improvement. Taylor & Francis Group, London and New York, pp. 160–196.
Goh, A. T. C. (2017). “Deterministic and reliability assessment of basal heave stability for braced excavations with jet grout base slab.” Engineering Geology, 218, 63–69.
Liu, Y., Lee, F. H., Quek, S. T., Chen, J. E., and Yi, J. T. (2015). “Effect of spatial variation of strength and modulus on the lateral compression response of cement-admixed clay slab.” Géotechnique, 65(10), 851–865, http://dx.doi.org/10.1680/ jgeot.14.P.254.
Liu, Y., Jiang, Y. J., Xiao, H., and Lee, F. H. (2017). “Determination of representative strength of deep cement-mixed clay from core strength data.” Géotechnique, 67(4), 350–364, https://doi.org/10.1680/jgeot.16.P.105.
Navin, M. P., and Filz, G. M. (2005). “Statistical Analysis of Strength Data from Ground Improved with DMM Column,” International Conference on Deep Mixing Best Practice and Recent Advances, Swedish Deep Stabilization Research Centre, Stockholm, Sweden, Vol1. 1, 145–154.
OPTUM G2. (2021). Geotechnical analysis software-Optum CE, Academic Version.
Page, R. J., Ong, J. C. W., Osborne, N., and Shirlaw, J. N. (2006). “Jet Grouting for Excavations in Soft Clay – Design and Construction Issues.” International Conference on Deep Excavations, 28-30 June 2006, Singapore.
Pittaro, G. A. (2016). “Use of pressure relief wells to check ground improvement tensile strains in deep excavations.”, 19th Southeast Asian Geotechnical Conference & 2nd AGSSEA Conference (19SEAGC & 2AGSSEA), 31 May – 3 June 2016, Kuala Lumpur.
Pittaro, G. A., and Murphy, G. (2018). “Deep Excavations with Ground Improvement – A Study Using Statistics and Back Analysis from a Monitored Excavation.” Conference: Underground Singapore, 2018.
Shirlaw, J. N. (2003). Jet grouting soft clays for tunneling and deep excavations – design and construction issues. Proc. 3rd Int. Conf., Grouting and Grout Treatment. ASCE 1, pp. 257–268.
Tyagi, A., Liu, Y., Pan, Y.-T., and Lee, F. H. (2020). “Equivalent strength for tunnels in cement-admixed soil columns with spatial variability and positioning error.” ASCE J. Geotech. Geoenviron. Eng., 146 (10): 04020101.
Tyagi, A., and Tamta, D. (2023). “Equivalent Design Strengths for Spatially Variable Cement-Treated Soil Slope.” ASCE International Journal of Geomechanics, 23(11), 06023017.
Tyagi, A., Zulkefli, M. F. B., Pan, Y., Goh, S. H., and Lee, F. H. (2017). Failure modes of tunnels with improved soil surrounds. ASCE J. Geotech. Geoenviron. Eng. 143 (11): 04017088.
Zhang, W., Li, Y., Goh, A. T. C., and Zhang, R. (2020). “Numerical study of the performance of jet grout piles for braced excavations in soft clay.” Computers and Geotechnics, Elsevier, 124(2020), 103631.
Information & Authors
Information
Published In
IFCEE 2024
Pages: 227 - 236
History
Published online: May 3, 2024
ASCE Technical Topics:
- Continuum mechanics
- Degrees of freedom
- Displacement (mechanics)
- Engineering fundamentals
- Engineering materials (by type)
- Engineering mechanics
- Geomechanics
- Geometry
- Geotechnical engineering
- Heave
- Material mechanics
- Material properties
- Materials engineering
- Mathematics
- Slabs
- Soil cement
- Soil mechanics
- Soil properties
- Soil strength
- Solid mechanics
- Spatial variability
- Strength of materials
- Structural engineering
- Structural mechanics
- Structural members
- Structural systems
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