Skip to main content
SpringerLink
Log in

Model Studies on Load Sharing for Shaft and Tip of Pile Groups in Saturated and Unsaturated Soils

  • Original Paper
  • Published:
Geotechnical and Geological Engineering Aims and scope Submit manuscript

Abstract

The behavior of pile foundation is dictated by its structural properties and stiffness and strength of the soil supporting the pile. This complexity is further increased when the soil is in partially saturated condition. In this work, an attempt has been done to investigate the influence of matric suction on the behavior of single pile and pile group, and the amount of increase in the bearing capacity due to the influence of this suction. The load transfer for shaft and tip of pile groups embedded in soil with different properties (saturated and unsaturated) is investigated. First, the stresses below the center of piles are measured by a soil pressure transducer located at a depth of 0.25 L, (L = length of pile). These stresses are transferred directly to pile tip according to approximate 2 V:1 H method and then converted to load at the tip and shaft of pile. The general trend is that in a single pile, at the start of load applying, the percentage of distributed load is 70% for shaft and 30% for tip, then as the applied load increases, the pile settles and a differential movement between the soil and pile occurs, creating more adhesion between the soil resulting in increase in shaft capacity. For pile groups, the same trend is obtained, but the percentage of load transferred to the shaft increases as the number of piles increases, in contrast to the load transferred to the tip. The results showed that the sharing of load between shaft and end resistance for single pile in saturated soil is halved when the pile reaches its ultimate resistance, while this response is different for unsaturated soil where the load is transferred as a whole to the pile tip at approximately the intermediate stages of loading according to the analysis criteria adopted.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11
Fig. 12
Fig. 13
Fig. 14
Fig. 15
Fig. 16
Fig. 17
Fig. 18
Fig. 19
Fig. 20
Fig. 21
Fig. 22
Fig. 23
Fig. 24
Fig. 25
Fig. 26
Fig. 27
Fig. 28
Fig. 29
Fig. 30
Fig. 31
Fig. 32
Fig. 33

Similar content being viewed by others

References

  • Al-Omari RR, Fattah MY, Kallawi AM (2017) Stress transfer from pile group in saturated and unsaturated soil using theoretical and experimental approaches. In: MATEC web of conferences 120, 06006, (2017) ASCMCES-17, 6006, international conference on advances in sustainable construction materials & civil engineering systems (ASCMCES-17), University of Sharjah, UAE. https://doi.org/10.1051/matecconf/20171200

  • Al-Omari RR, Fattah MY, Kallawi AM (2018) Laboratory study on load carrying capacity of pile group in unsaturated clay. Arab J Sci Eng 44:4613–4627. https://doi.org/10.1007/s13369-018-3483-9

    Article  Google Scholar 

  • Bowles JE (1996) Foundation analysis and design. McGraw-Hill, New York

    Google Scholar 

  • Fattah MY, Yahya AY, Ahmed BA (2012) Total and matric suction measurement of unsaturated soils in Baghdad region by filter paper method. J Eng 18(5):611–620

    Google Scholar 

  • Fattah MY, Ahmed MD, Mohammed HA (2013) Behavior of Partially Saturated Cohesive Soil under Strip Footing. J Eng 19(3):298–311

    Google Scholar 

  • Fattah MY, Salim NM, Mohsin IM (2014) behavior of single pile in unsaturated clayey soils. Eng Technol J 32(3):763–787

    Google Scholar 

  • Khallawi AM (2015) Load transfer of pile group in saturated and unsaturated clayey soil. Ph.D. thesis, Civil Engineering Department, Al-Nahrain University, Iraq

  • Lu N, Godt JW, Wu DT (2010) A closed-form equation for effective stress in unsaturated soil. Water Resour Res 46:1–14

    Google Scholar 

  • Machmer BM (2012) Understanding the behavior of a pile foundation in unsaturated soils subjected to lateral loading, M.Sc. thesis, Clemson University

  • Mohamed FMO, Vanapalli SK (2006) Laboratory investigations for the measurement of the bearing capacity of an unsaturated coarse-grained soil. In: 59th Canadian geotechnical conference, BC, Vancouver

  • Prakash S, Sharma HD (1990) Pile foundations in engineering practice. Wiley, Hoboken

    Google Scholar 

  • Vanapalli SK, Taylan ZN (2011) Estimation of the shaft capacity of model piles in a compacted fine-grained unsaturated soil. In: Proceeding of 14th pan-am conf. on soil mechanics and geotechnical engineering & 64th canadian geotechnical conference

  • Vanapalli SK, Oh WT (2011) Interpretation of the bearing capacity of an unsaturated soils extending the effective and total stress approaches. In: Proceeding of 5th international conference on UNSAT, 2010, pp 1223–1229

  • Vanapalli SK, Taylan ZN (2012) Design of single piles using the mechanics of unsaturated soils. Int J Geomate 2(1):197–204

    Google Scholar 

  • Uchaipichat A (2012) Variation of Pile Capacity in Unsaturated Clay Layer with Suction. Electron J Geotech Eng 17:2425–2433

    Google Scholar 

  • U.S. Army Corps of Engineers (1991) Design of pile foundations. Engineer Manual. EM 1110-2-2906, pp 4–10

Download references

Author information

Authors and Affiliations

  1. Civil Engineering Department, University of Technology, Baghdad, Iraq

    Mohammed Y. Fattah

  2. Civil Engineering Department, Al-Farabi University College, Baghdad, Iraq

    Raid R. al-Omari

  3. University of Baghdad, Baghdad, Iraq

    Abbas M. Kallawi

Authors
  1. Mohammed Y. Fattah
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Raid R. al-Omari
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Abbas M. Kallawi
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Mohammed Y. Fattah.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Fattah, M.Y., al-Omari, R.R. & Kallawi, A.M. Model Studies on Load Sharing for Shaft and Tip of Pile Groups in Saturated and Unsaturated Soils. Geotech Geol Eng 38, 4227–4242 (2020). https://doi.org/10.1007/s10706-020-01291-9

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10706-020-01291-9

Keywords

Search

Navigation