INSTRUMENTED PILE LOAD TESTING WITH DISTRIBUTED OPTICAL FIBRE STRAIN SENSOR

Authors

  • Hisham Mohamad UTM Construction Research Centre, Faculty of Civil Engineering, Universiti Teknologi Malaysia, 81310 UTM Johor Bahru, Johor, Malaysia
  • Bun Pin Tee UTM Construction Research Centre, Faculty of Civil Engineering, Universiti Teknologi Malaysia, 81310 UTM Johor Bahru, Johor, Malaysia

DOI:

https://doi.org/10.11113/jt.v77.6381

Keywords:

Bored pile, Fibre-Optic sensing, BOTDA, maintain load test

Abstract

An instrumented pile load test was conducted for a 1.2m diameter bored pile at Putrajaya to verify pile performance towards geotechnical design. This test pile was instrumented with new monitoring technique using distributed strain sensing known as Brillouin Optical Time Domain Analysis (BOTDA) and compared with conventional sensors, i.e. vibrating wire strain gauge, LVDT (linear variable differential transformer) and dial gauge. This manuscript includes the description of subsurface conditions consisting of weathered granitic residual soils, test pile installation and instrumentation setup of Maintain Load Test (MLT). Field measurement results such as the load transfer response and average unit shaft resistance using the distributed fibre optic strain sensor were well matched with the results using the conventional sensors. However, the distributed fibre optic strain sensor has the added advantage of detecting the localized defect such as pile necking, bending, and overall behaviour of bored pile effectively. 

References

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Mohamad, H., Soga, K. and Bennett, P.J. 2009. Fibre Optic Installation Techniques For Pile Instrumentation. Proceedings of the 17th International Conference on Soil Mechanics on Soil Mechanics and Geotechnical Engineering: The Academia and Practice of Geotechnical Engineering. IOS Press. 3:1873-1876.

Mohamad, H., Soga K., Pellew, A. and Bennett, P.J. 2011. Performance Monitoring of a Secant Piled Wall Using Distributed Fiber Optic Strain Sensing. Journal of Geotechnical and Geoenvironmental Engineering. 137(12):1236-1243.

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Soga, K., Mohamad, H. and Bennett, P.J. 2008. Distributed Fiber Optics Strain Measurements For Monitoring Geotechnical Structures. 6th International Conference on Case Histories in Geotechnical Engineering (Symposium in honor of Professor James K Mitchell). Arlington, USA.

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Published

2015-11-23

Issue

Section

Science and Engineering

How to Cite

INSTRUMENTED PILE LOAD TESTING WITH DISTRIBUTED OPTICAL FIBRE STRAIN SENSOR. (2015). Jurnal Teknologi (Sciences & Engineering), 77(11). https://doi.org/10.11113/jt.v77.6381