Preliminary Report on the Effect of Pre-Boring on the Mobilized Friction Capacity of Pile Foundation Hydraulically Jacked into Expansive Soil

Gogot Setyo Budi




Abstract


Pre-drilling was performed to reduce lateral earth pressure generated by pile foundation hydraulically jacked into expansive soil. Nineteen prestressed-precast spun concrete pile with diameter of 800 mm were penetrated into expansive soil up the depth of 40 m. Pre-drilling with diameter of 700 mm was carried out up to the depth of 12.5 m. Penetration loads required to install the piles, which was displayed on the built-in pressure panel, were recorded every 1 m interval. The load that was consisted of merely shaft friction was then used to find out the mobilized skin friction between pile shaft and its surrounding soils. The calculated mobilized skin friction was correlated to the value of Standard Penetration Test (NSPT) and compared to Decourt formula. The result shows that skin friction calculated using Decourt formula relatively conservative compared to those determined from the records of field penetration. The upper bound of mobilized skin friction can be defined by modifying Decourt formula.


Keywords


Expansive soils; jack-in piles; shaft friction.

References


  1. Poulos, H.G., Effect of Pile Driving on Adjacent Piles in Clay, Canadian Geotechnical Journal, 31, 1994, pp. 856-867.[CrossRef]
  2. Broms, B.B., Precast Piling Practice, Thomas Telford LTD, London, 1981.
  3. Transport and Main Roads Specifications, MRTS65, Technical Specification, State of Queensland Department of Transport and Main Roads, April, 2011.
  4. Operation’s Manual JVY700, CHTC Jove Heavy Industry Co., Ltd-China.
  5. Data Persada, Soil Investigation Report, November, 2013.
  6. Decourt, L., Prediction of the Bearing Capacity of Piles Based Exclusively on Values of the SPT, Proceeding of the Second European Symposium on Penetration Testing, Amsterdam, 24-27 May, 1982, pp. 29-34.
  7. Schmertmann, J.H., Static Cone Penetrometers for Soil Exploration, Civil Engineering, 37(6), 1967, pp. 71-73.
  8. Bromham, S.B. and Styles, J.R., An Analysis of Pile Loading Tests in Stiff Clay, Proceeding of the First Australian- New Zealand Conference on Geomechanics, Melbourne, 1, 1971, pp. 246-253.
  9. Meyerhof, G.G., Bearing Capacity and Settlement of Pile Foundations, The Eleventh Terzaghi Lecture, November 5, 1975, Journal of Geotechnical Engineering, ASCE, 102(GT-3), 1976, pp. 195-228.


Full Text: PDF

Instructions for Preparing Papers for CED.docx
The Journal is published by The Institute of Research & Community Outreach - Petra Christian University.

©All right reserved 2016.Civil Engineering Dimension, ISSN: 1410-9530, e-ISSN: 1979-570X

 

View My Stats


Copyright © Research Center Web-Dev Team