Volume 3, Issue 3 September 2018

ReportHistory of Cambridge – GIKEN collaboration research (Part3)
Yukihiro Ishihara, Giken, Ltd.
Stuart Haigh, University of Cambridge
The Cambridge – Giken collaboration research started in 1994, based on the strong awareness of Mr. Akio Kitamura,President of Giken, Ltd., of issues relating to construction. Every summer two students visit Kochi, Japan, to carry out field
and model tests using the press-in machines and other facilities of Giken, in order to learn this technology by experience.
In some cases, they also conduct model tests or numerical analyses in their own laboratories on their return to Cambridge.
In this report, research related to the tests carried out in Kochi from 2010 to 2018 are presented.
[2010-2011]
Project title
Outline of tests in Kochi::

Main students
Related publications::[2011-2012]
Project title
Outline of tests in Kochi

Main students
Related publications

Reduction of penetration resistance during rotary press-in
Two types of piles were used in this project: a closed-ended tubular pile with an outside
diameter of 318.5 mm and an open-ended tubular pile with an outside diameter of500mm. The closed-ended pile was installed by standard press-in and rotary press-in atdifferent penetration rates and rotation rates. It was found that the base resistance wasreduced by increasing the penetration rate, showing a trend explained based on Finnie
factor, in which the rate effect is attributed to the drainage condition. The rotation wasconfirmed to reduce the shaft resistance significantly but have little influence on the baseresistance. The reduction of the shaft resistance was greater at larger velocity ratio (theratio of the rotation rate to the penetration rate). This was attributed to a more horizontal
direction of friction mobilized at the pile-soil interface. On the other hand, the extent ofplugging was not mitigated by rotation; the length of the soil column inside a pile installedby rotary press-in was not shorter than that installed by standard press-in. This wasconcluded to be due to the difference in the ground condition.
Thomas Bond and Travis Winstanley
Bond, T. 2011. Rotary jacking of tubular piles. M.Eng. Project Report, Cambridge
University Department of Engineering, 50p.
Nishigawa, M., Okada, K., Bond, T., Yamane, T., Ishihara, Y. and Kitamura, A. 2011.
Reduction of friction in rotary jacking. Proceedings of the 3rd IPA International Workshopin Shanghai, Press-in Engineering 2011, pp. 107-113.

: Spatial distribution of pore water pressure during press-in: Three closed-ended piles with the outside diameter of 318.5mm were used in this project.
Each pile was equipped with a load cell on its base, 5 pore water pressure transducers
and 5 earth pressure transducers on its shaft. Two of the piles were used as measurement
piles while the other one was pressed-in as a test pile, as shown in Figure 1. The distance
between the test pile and the measurement piles were maintained either as 1, 2, 3 or 5
times the outside diameter of the piles. During press-in, the pore water pressure
measured by the measurement piles increased to its peak value until the pile base passed
the depth of the transducers, and then started to decrease to a residual value. It wasconfirmed that the spherical cavity expansion analysis provides a lower bound of the peakvalues of pore water pressure during press-in.
: Travis Winstanley and Ewa Hazla: Winstanley, T., 2012. The significance of pore water pressures on press-in piles. M.Eng.
Project Report, Cambridge University Department of Engineering, 50p.

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Volume 3, Issue 3 September 2018

Figure 1 (from Winstanley (2012))[2012-2013]
Project title
Outline of tests in Kochi::

Main students
Related publications::[2013-2014]
Project title
Outline of tests in Kochi::

Main students
Related publications::

Reduction of friction during rotary cutting press-in of an open-ended tubular pile in sandOpen-ended tubular piles with the outside diameter of 800mm were used in this project.
The piles were installed into a dense sandy ground by rotary cutting press-in method.
When the pile was processed to have surface projections, which had been expected tobe effective in reducing the shaft resistance, the penetration resistance was greater thanwhen the pile did not have the surface projections, which was contrary to the expectation.
When the non-processed pile was continuously rotated at a constant depth, therotational torque did not keep decreasing with an increasing rotational displacement.
This result was in contrast with the results confirmed in the previous year that therotational torque decreased by around 50% with an increasing rotational displacement
when a pile with the outside diameter of 318.5mm embedded in a soft alluvial ground
was rotated at a constant depth.
Ewa Hazla and Gongyan GaoHazla, E., 2013. Rotary press-in piling in hard ground. M.Eng. Project Report, Cambridge
University Department of Engineering, 50p.
Performance of steel sheet pile walls
Three types of cantilevered sheet pile walls were dealt with in this project. One was the‘Normal wall’ in which sheet piles were embedded vertically. Another was the ‘Slanting
wall’ where sheet piles were embedded with the inclination angle of 5 degrees. The otherwas the ‘Implant preload wall’ in which sheet piles were embedded with the inclination
angle at their base of 5 degrees and were elastically deflected toward the excavation side,
as shown in Figure 2. When the backside surcharge was applied to the wall, the horizontal
displacement of the walls was the largest in the Normal wall and the smallest in theImplant preload wall. Two underlying mechanisms were inferred. One was that thehorizontal loading history on the soil in the excavated bottom associated with thehorizontal displacement of the wall due to the preload increased the stiffness of the soil
when it responded to the second loading process associated with the backside surcharge.
The other was that the shear strength of the soil behind the wall was enhanced due tothe increased confinement stress associated with the elastic deflection of the wall.
Gongyan Gao and Glyn Stevens
Gao, G., 2014. Comparing performance of different sheet pile walls. M.Eng. Project
Report, Cambridge University Department of Engineering, 50p.
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Volume 3, Issue 3 September 2018
Ishihara, Y., Ogawa, N., Okada, K. and Kitamura, A., 2015. Implant Preload Wall: a novel
self-retaining wall with high performance against backside surcharge. Proceedings of the
5th IPA International Workshop in Ho Chi Minh, Press-in Engineering 2015, pp. 68-82.
Ogawa, N., Ishihara, Y. and Kitamura, A., 2017. Experimental study on deformation of selfretaining sheet pile wall due to excavation and backside surcharge. Journal of Japan
Society of Civil Engineers, Division C: Geotechnics, pp. 62-75. (in Japanese)

Figure 2[2014-2015]Project title
Outline of tests in Kochi::

Main students
Related publications::

Mechanism of water-binding during rotary press-in in dense sandWater-binding is a phenomena that is sometimes encountered when installing a pile insand assisted with water injection. Muddy water coming up to the ground surface along
the pile shaft, which will be observed when a pile is being installed smoothly, is lost andthe penetration resistance suddenly increases. To investigate into the mechanism ofwater-binding, a circular and a semi-circular model piles with the outside diameter of
48.6mm and a soil tank with the width and the horizontal depth of 1000mm and thedepth of 1200mm were used in this project. The soil tank had an acrylic plate on one ofits four sides, and a saturated model ground was prepared inside the soil tank by mixing
a saturated silica sand #7 using a stirring bar. The semi-circular pile was pressed-in
assisted by water injection against the acrylic plate, so that the penetration process canbe visualized. The circular pile was installed by rotary press-in assisted by water injection
at the center of the model ground, with different penetration rates, rotational rates andflowrates to confirm the conditions on which the water-binding is triggered. From thetests using the semi-circular piles, the process of the creation of ‘interface liquefaction’and the disappearance of it (i.e. water-binding) was observed, and the three parameters
were identified as critical for sustaining the interface liquefaction: the water pressure atthe pile shoulder, the water pressure required to sustain the interface liquefaction andthe flowrate available for interface liquefaction. An analytical model was proposed byassuming that the cause of water-binding is the sufficient pressure in the liquefied region
to transmit all water though the pores, and was confirmed to be able to predict the depthof water-binding correctly for saturated sand.
Glyn Stevens and Andrei Dobrisan
Stevens, G., 2015. Mechanism of water binding during press-in in sand. M.Eng. Project
Report, Cambridge University Department of Engineering, 50p.

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Volume 3, Issue 3 September 2018[2015-2016]
Project title
Outline of tests in Kochi::

Main students
Related publications::[2016-2017]
Project title:

Outline of tests in Kochi:

Main students
Related publications::

Verification of the resilience of Implant levees against tsunami
Two sets of experiments were carried out in this project. One was to investigate thehorizontal load imposed by tsunami on a wall in an overflowing condition, by means ofmodel tests using an experimental facility called the Tsunami Simulator, as shown inFigure 3. The other was a static horizontal load tests on two piles with the same outside
diameter of 1000mm and different thicknesses of 12mm and 24mm, to observe thedeformation characteristics of piles embedded in dense sand beyond its elastic limit. The
results of the model tests showed that the tsunami load in an overflowing condition canbe safely estimated by an existing estimation method, excluding instantaneous loads
measured when the model tsunami hit the wall. Based on the results of the load tests, it
was confirmed that the stiffness and bending moment profile of the pile were wellestimated by DNV (1992). On the other hand, the horizontal capacity of the pile wasconfirmed to be underestimated by a factor of 2 by the p-y method, which has been
pointed out by many researchers.
Andrei Dobrisan and Yan Zhuang
Dobrisan, A., 2016. Suitability of jacked-in steel piles as tsunami defences. M.Eng. Project
Report,Cambridge
University Department ofEngineering, 48p.
Dobrisan, A., Haigh, S. K.
and Ishihara, Y. 2018.
Evaluating the efficiency ofjacked-in piles as tsunami
defences. Proceedings ofthe First International
Conference on Press-inFigure 3Engineering.
Design and construction of sheet pile retaining wall with and without the stabilization ofexcavation base
Two types of sheet pile pits were designed and constructed One was a square pit No.1
with a horizontal length of 8.4m, an embedment
depth of 10m and an excavated depth of 5m. The
6.0m
other was a rectangular pit No.2 with a horizontal
length of 8.4m and 6m, an embedment depth of
16.5m and an excavated depth of 9.5m. The
excavation base in the pit No.2 was stabilized by anumber of concrete columns before theexcavation, as shown in Figure 4. The deformation
1000mm8.4mof the wall due to the stabilization and the(from centerexcavation was measured manually by anto center)
inclinometer. The wall was pushed outwards dueto the stabilization and then pushed inwards dueto the excavation. Together with the results of FEM
analysis in which the stabilization process wasFigure 4
modelled by thermal expansion, the effectivenessof the stabilization was discussed qualitatively.
Yan Zhuang and Marla Gillow
Zhuang, Y., 2017. The effect of bottom stabilisation on sheet pile pit. M.Eng. Project
Report, Cambridge University Department of Engineering, 46p.

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Volume 3, Issue 3 September 2018[2017-2018]
Project title
Outline of tests in Kochi::Main students
Related publications::

Mechanism of water jetting
Two sets of sheet piles equipped withpore pressure transducers were used inthis project. One pile was installed prior
to the installation of another, so that thepore water pressure not only on theshaft of the pile being installed but also
in the ground at a certain distance fromthe pile being installed can be measured.
Results of detailed analysis of the datasuggested that a high stress region near
the base of the sheet pile caused a buildup of base resistance, preventing further
penetration of the pile, until enoughwater pressure was built up at the pilebase to reduce the stress of the highstress region. The high water pressure
was able to be built-up around the pilebase even in relatively permeable soils,
presumably because the repeated
Fiure 5 (from Gillow (2018))
penetration and extraction at a constantdepth range caused crushing of sandparticles, forming an impermeable filmin the pile base as shown in Figure 5.
Marla Gillow, Jennifer Chambers
Gillow, M. 2018. Water jetting for sheet piling in sandy soils. M.Eng. Project Report,
Cambridge University Department of Engineering, 49p.
Gillow, M., Haigh, S. K., Ishihara, Y., Ogawa, N. and Okada, K. 2018. Water jetting for sheet
piling. Proceedings of the First International Conference on Press-in Engineering.

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