Pile Side Resistance in Sands for the Unloading Effect and Modulus Degradation

C. F. Zhao; Y. Wu; C. Zhao; Q. Z. Zhang; F. M. Liu; F. Liu

doi:10.3989/mc.2019.03718

Authors

C. F. Zhao Department of Geotechnical Engineering, Tongji University https://orcid.org/0000-0002-0010-1819
Y. Wu Department of Geotechnical Engineering, Tongji University https://orcid.org/0000-0002-8366-9871
C. Zhao Department of Geotechnical Engineering, Tongji University - School of Engineering, Tibet University https://orcid.org/0000-0002-8973-9164
Q. Z. Zhang Department of Geotechnical Engineering, Tongji University https://orcid.org/0000-0002-7007-5871
F. M. Liu Department of Geotechnical Engineering, Tongji University https://orcid.org/0000-0002-5517-162X
F. Liu Department of Geotechnical Engineering, Tongji University https://orcid.org/0000-0001-9349-2400

DOI:

https://doi.org/10.3989/mc.2019.03718

Keywords:

Concrete, Composite, Stability, Mechanical properties, Characterization

Abstract

A total of 36 groups of sand-concrete interface loading and unloading direct shear tests were used to analyze the mechanical properties of the pile side-soil interface. The test results show that the interface residual shear stress for the same applied normal stress tends to be constant for the rough sand-concrete interface. The initial shear modulus and peak shear stress of the interface both decrease with the degree of unloading and increase with the interface roughness. The maximum amount of interface shear dilatancy increases with the degree of unloading, and the maximum amount of interface shear shrinkage decreases with unloading for the same interface roughness. A pile side resistance-displacement model is established using the shear displacement method. The proposed function considers both the radial unloading effect and modulus degradation of soil around the pile. The effect of radial unloading and interface roughness on the degradation of the equivalent shear modulus is analyzed using a single fitting parameter b. Good agreement of the proposed model is confirmed by applying the direct shear tests of the 36 groups.

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References

Ni, P. P.; Song, L. H.; Mei, G. X.; Zhao, Y. L. (2017) Generalized nonlinear softening load-transfer model for axially loaded piles. Int. J. Geomech. 17 [8], 04017019. https://doi.org/10.1061/(ASCE)GM.1943-5622.0000899

Guo, W. D. (2001) Pile capacity in nonhomogeneous softening soil. Soils Found. 41 [2], 111-120. https://doi.org/10.3208/sandf.41.2_111

Seed, H. B.; Reese, L. C. (1957) The action of soft clay along friction piles. Transactions of the ASCE. 122 [1], 731-754.

Chow, Y. K. (1986) Analysis of vertically loaded pile groups. Int. J. Numer. Anal. Meth. Geomech. 10 [1], 59-72. https://doi.org/10.1002/nag.1610100105

Chow, Y. K. (1989) Axially loaded piles and pile groups embedded in a cross-anisotropic soil. Geotechnique. 39 [2], 203-212. https://doi.org/10.1680/geot.1989.39.2.203

Mu, L. L.; Chen, Q. S.; Huang, M. S.; Basack, S. (2017) Hybrid approach for rigid piled-raft foundations subjected to coupled loads in layered soils. Int. J. Geomech. 17 [5], 04016122. https://doi.org/10.1061/(ASCE)GM.1943-5622.0000825

Randolph, M. F.; Wroth, C. P. (1978) Analysis of deformation of vertically loaded piles. J. Geotech. Eng. Div. 104 [12], 1465-1488.

Randolph, M. F.; Wroth, C. P. (1979) An analysis of the vertical deformation of pile groups. Geotechnique. 29 [4], 423-439. https://doi.org/10.1680/geot.1979.29.4.423

Zhang, Q. Q.; Zhang, Z. M. (2011) Study on interaction between dissimilar piles in layered soils. Int. J. Numer. Anal. Meth. Geomech. 35 [1], 67-81. https://doi.org/10.1002/nag.893

Poulos, H. G.; Davis, E. H. (1968) The settlement behaviour of single axially loaded incompressible piles and piers. Geotechnique. 18 [3], 351-371. https://doi.org/10.1680/geot.1968.18.3.351

Wang, W.; Yang, M. (2006) An improved elastic analysis method of pile foundation under vertical loading. Roc. Soil. Mech. 27 [8], 1403-1406 (in Chinese).

Xu, K. J.; Poulos, H. G. (2000) General elastic analysis of piles and pile groups. Int. J. Numer. Anal. Meth. Geomech. 24 [15], 1109-1138. https://doi.org/10.1002/1096-9853(20001225)24:15<1109::AID-NAG72>3.0.CO;2-N

Ai, Z. Y.; Han, J. (2009) Boundary element analysis of axially loaded piles embedded in a multi-layered soil. Comput. Geotech. 36 [3], 427-434. https://doi.org/10.1016/j.compgeo.2008.06.001

Cheung, Y. K.; Tham, L. G.; Guo, D. J. (1988) Analysis of pile group by infinite layer method. Geotechnique. 38 [3], 415-431. https://doi.org/10.1680/geot.1988.38.3.415

Desai, C. S. (1974) Numerical design analysis for piles in sands. J. Geotech. Eng. Div. 100 [6], 613-635. https://doi.org/10.1016/0148-9062(74)91242-X

Lee, C. Y. (1991) Discrete layer analysis of axially loaded piles and pile groups. Comput. Geotech. 11 [4], 295-313. https://doi.org/10.1016/0266-352X(91)90014-7

Sheng, D. C.; Eigenbrod, K. D.; Wriggers, P. (2005) Finite element analysis of pile installation using large-slip frictional contact. Comput. Geotech. 32 [1], 17-26. https://doi.org/10.1016/j.compgeo.2004.10.004

Trochanis, A. M.; Bielak, J.; Christiano, P. (1991) Three - dimensional nonlinear study of piles. J. Geotech. Eng. 117 [3], 429-447. https://doi.org/10.1061/(ASCE)0733-9410(1991)117:3(429)

Everett, J. P. (1991) Load transfer functions and pile performance monitoring. Int. J. Roc. Mech. Min. Sciences. 30 [1], 229-234.

Li, Y. H.; Wang, W. D.; Wu, J. B. (2015) Bearing deformation of large-diameter and super-long bored piles based on pile shaft generalized shear model. Chin. J. Geotech. Eng. 37 [12], 2157-2166 (in Chinese).

Guo, W. D.; Randolph, M. F. (1997) Vertically loaded piles in non-homogeneous media. Int. J. Numer. Anal. Meth. Geomech. 21 [8], 507-532. https://doi.org/10.1002/(SICI)1096-9853(199708)21:8<507::AID-NAG888>3.0.CO;2-V

Zhu, H.; Chang, M. F. (2002) Load transfer curves along bored piles considering modulus degradation. J. Geotech. Geoenviron. Eng. 128 [9], 764-774. https://doi.org/10.1061/(ASCE)1090-0241(2002)128:9(764)

Lade, P. V.; Duncan, J. M. (1976) Stress-path independent behavior of cohesionless soil. J. Geotech. Eng. Div. 102 [1], 51-68.

Lambe, T. W. (1967) Stress path method. J. Soil. Mech. Found. Div. 93 [6], 309-331.

Wang, Z. J.; Xie, X. Y.; Wang, J. C. (2012) A new nonlinear method for vertical settlement prediction of a single pile and pile groups in layered soils. Comput. Geotech. 45, 118-126. https://doi.org/10.1016/j.compgeo.2012.05.011

Yang, J. J. (2005) Similarity theory and structural model test. Wuhan University of Technology Press, Wuhan. (in Chinese)

Zhao, C. F.; Wu, Y.; Zhao, C.; Tao, G. X. (2018) Experimental research on the clay-concrete interface shear behaviors considering the roughness and unloading Effect. Proc. of GeoShanghai 2018 International Conf. Fundamentals of soil behaviours, 522-530. https://doi.org/10.1007/978-981-13-0125-4_58

Dove, J. E.; Jarrett, J. B. (2002) Behavior of dilative sand interfaces in a geotribology framework. J. Geotech. Geoenviron. Eng. 128 [1], 25-37. https://doi.org/10.1061/(ASCE)1090-0241(2002)128:1(25)

Zhang, G.; Zhang, J. M. (2003) Development and application of cyclic shear apparatus for soil-structure interface. Chin. J. Geotech. Eng. 25 [2], 149-153 (in Chinese).

Zhang, G.; Zhang, J. M. (2004) Experimental study on monotonic behavior of interface between soil and structure. Chin. J. Geotech. Eng. 26 [1], 21-25 (in Chinese).

Fahey, M.; Carter, J. P. (1993) A finite element study of the pressuremeter test in sand using a nonlinear elastic plastic model. Can. Geotech. J. 30 [2], 348-362. https://doi.org/10.1139/t93-029

Tomlinson, M. J.; Woodward, J. (1977). Pile design and construction practice, Fourth Edition. A View Point Publications, London.

Chandler, R. J. (1968) The shaft friction of piles in cohesive soils in terms of effective stress. Civil Eng and Public Works Review. 63 [738], 48-51.

Focht, J.; Vijayvergiya, V. (1972) A new way to predict capacity of piles in clay. Proc. 4th Offshore Technology Conf. vol. 2, 865-874. https://doi.org/10.4043/1718-MS PMid:4205441

Mayne, P. W.; Kulhawy, F. H. (1982) K0-OCR relationships in soil. J. Geotech. Eng. Div. 108 [6], 851-872.

Ruiz, M. E. (2005). Study of axially loaded post grouted drilled shafts using CPT based load transfer curves. Master Thesis, Civil Engineering. University of Puerto Rico.

Mayne, P. W.; Schneider, J. A. (2001) Evaluating axial drilled shaft response by seismic cone. Foundations and ground improvement, Geotechnical Special Publication. 113, 655-669.

Kulhawy, F. H. (1984) Limiting Tip and Side Resistance : fact or fallacy. Proc. Conf. on Analysis and Design of Pile Foundations. ASCE Convention, San Francisco, California. 80-98.

Wang, W. B.; Yang, M. (2005) Elasto-plastic analysis for vertical pile based on extended compatibility of deformation. Chin. J. Geotech. Eng. 27 [12], 1442-1446 (in Chinese).