Influence of cavity-forming processes on the uplift resistance of bulb piles
)Abstract
The uplift resistances and failure modes of bulb piles with variable sections are quite different in the cutting or extruding construction modes. Through numerical simulation, the extrusion effects on the soil around the pile are estimated in this study. How the load transfers along a bulb pile is analyzed. The physical state variables of the soil around the pile are estimated, including the von Mises stress, horizontal stress, vertical stress, void ratio, displacement, and resistance. Owing to the extrusion effects, the influence range of the physical state variables increases. The greater the initial compactness of the soil around the pile is, the greater the influence range of the compaction on the physical state variables of the soil around the pile. When the compactness of the soil around the pile is high, the ultimate bearing capacity of the pile can be increased by 30% because of the extrusion effect. When the compactness is relatively small, the ultimate bearing capacity can also increase by more than 20%. The improvement in the pile bearing capacity due to the extrusion effect is reflected mainly in the enhanced plate resistance, whereas the improvement in the side resistance is not significant.
References
G. S. Jain, S. P. Gupta. Deformation of soil around a multi-under-reamed pile. Indian Concr J, 1972, 46: 239–241.
D. X. He, B. H. Shen. DX extruding device and DX pile with multi-under-extruding branches. Ind Constr, 2001, 31: 27–31. (in Chinese)
D. H. Zhang, M. S. Wang. The application of DX rotary and squeezed pile on railway bridge engineering. Strategic Study CAE, 2009, 11: 92–96. (in Chinese)
C. Prakash, V. Ramakrishna. Lateral load capacity of underreamed piles—An analytical approach. Soils Found, 2004, 44: 51–65.
J. A. Peter, N. Lakshmanan, P. D. Manoharan. Investigations on the static behavior of self-compacting concrete under-reamed piles. J Mater Civil Eng, 2006, 18: 408–414.
T. Honda, Y. Hirai, E. Sato. Uplift capacity of belled and multi-belled piles in dense sand. Soils Found, 2011, 51: 483–496.
D. E. Harris, G. S. P. Madabhushi. Uplift capacity of an under-reamed pile foundation. Proc Inst Civ Eng Geotech Eng, 2015, 168: 526–538.
H. Mroueh, I. Shahrour. Three‐dimensional finite element analysis of the interaction between tunneling and pile foundations. Int J Numer Anal Methods Geomech, 2002, 26: 217–230.
K. K. Tho, C. F. Leung, Y. K. Chow, et al. Eulerian finite-element technique for analysis of jack-up spudcan penetration. Int J Geomech, 2012, 12: 64–73.
T. Pucker, J. Grabe. Numerical simulation of the installation process of full displacement piles. Comput Geotech, 2012, 45: 93–106.
G. Qiu, J. Grabe. Numerical investigation of bearing capacity due to spudcan penetration in sand overlying clay. Can Geotech J, 2012, 49: 1393–1407.
A. F. H. Rooz, A. Hamidi. A numerical model for continuous impact pile driving using ALE adaptive mesh method. Soil Dyn Earthquake Eng, 2019, 118: 134–143.
I. Herle, D. Kolymbas. Hypoplasticity for soils with low friction angles. Comput Geotech, 2004, 31: 365–373.
D. Mašín. Clay hypoplasticity with explicitly defined asymptotic states. Acta Geotech, 2013, 8: 481–496.
S. Wang, W. Wu. A simple hypoplastic model for overconsolidated clays. Acta Geotech, 2021, 16: 21–29.
R. Wang, J. M. Zhang, G. Wang. A unified plasticity model for large post-liquefaction shear deformation of sand. Comput Geotech, 2014, 59: 54–66.
G. Gudehus. A comprehensive constitutive equation for granular materials. Soils Found, 1996, 36: 1–12.
E. Bauer. Calibration of a comprehensive hypoplastic model for granular materials. Soils Found, 1996, 36: 13–26.
京公网安备11010802044758号