 |
 |
 |
 |
 |
 |
Sains
Malaysiana 46(11)(2017): 2231-2239 http://dx.doi.org/10.17576/jsm-2017-4611-25 Comparative
Analysis of Load Responses and Deformation for Crust Composite
Foundation and Pile-supported Embankment YING WANG1, YONGHUI CHEN2*,
ZHENHUA HU1, QIANG FENG1 & DESEN KONG1 1Shandong Provincial Key Laboratory of Civil Engineering, Disaster
Prevention and Mitigation Shandong University of Science and Technology, Qingdao 266590, China 2Geotechnical Research
Institute, Hohai University, Nanjing 210098, China Received: 8 January 2017/Accepted: 8 June 2017 ABSTRACT Ground improvement using artificial crust composite foundation, consisting
of stabilization of soft clay and composite foundation, is an
effective technique for the treatment of deep soft soil layers
under infrastructure embankments. In this study, the load responses
and settlement performance of this improvement technique were
investigated using two centrifuge model tests to compare the
variations of the vertical deformation, pore water pressure,
axial force of the piles and tensile stress at the bottom of
the artificial crust in the crust composite foundation with
those in pile-supported embankment. The results of centrifuge
model tests showed that the load responses and settlement performance
of artificial crust composite foundation was different from
the pile-supported embankment, which displayed mainly that the
final middle settlement of crust composite foundation can be
reduced by about 15% compared with those of pile-supported embankment
with the same length of pile and construction cost. The deformation
of the crust with the characteristics of the plate was found
based on the change of the tensile stress. Additionally, the
excess pore water pressure in the crust composite foundation
was lower owing to the stress diffusion effect of the crust
during the loading period and the dissipation rate of excess
pore water pressure was slower due to lower permeability of
the crust at the same loading period. Eventually, the axial
force of the middle piles was reduced. At the same time, the
boundary stress was functioned with the crust, the axial force
of the side piles was improved. The comparison of measured and
calculated results was carried out using the stress reduction
ratio, the result shows that the bearing capacity of the subsoil
in the crust composite was improved. Keywords: Artificial crust composite foundation; centrifuge model test;
pile-supported embankment; soft clay; stabilization ABSTRAK Pembaikan tanah yang menggunakan asas komposit kerak tiruan, terdiri daripada
penstabilan tanah liat lembut dan komposit asas, merupakan teknik
yang berkesan untuk rawatan tanah lembut lapisan dalam di bawah
infrastruktur benteng. Dalam kajian ini, beban tindak balas
tindakan dan prestasi penempatan dalam teknik pembaikan ini
dikaji menggunakan dua model ujian pengemparan untuk membandingkan
perbezaan canggaan menegak, tekanan air liang, daya paksi cerucuk
dan tekanan tegangan di bahagian bawah kerak tiruan dalam asas
komposit kerak dengan cerucuk disokong benteng. Keputusan ujian
model pengemparan menunjukkan bahawa beban tindak balas dan
prestasi penempatan asas komposit kerak tiruan adalah berbeza
daripada cerucuk disokong benteng, yang memaparkan asas penempatan
tengah akhir, asas kerak komposit boleh dikurangkan kira-kira
15% berbanding dengan cerucuk disokong benteng dengan panjang
cerucuk serta kos pembinaan yang sama. Canggaan kerak ini dengan
ciri plat dijumpai berdasarkan perubahan tekanan tegangan. Di
samping itu, tekanan air liang lebihan dalam asas komposit kerak
adalah lebih rendah disebabkan kesan penyebaran tekanan kerak
pada sepanjang tempoh bebanan dan kadar pelesapan tekanan air
liang lebihan adalah lebih perlahan disebabkan oleh kadar resapan
kerak yang lebih rendah pada tempoh beban yang sama. Kesimpulannya,
daya paksi cerucuk di bahagian telah telah dikurangkan. Pada
masa yang sama, tekanan sempadan berfungsi dengan kerak maka
daya paksi cerucuk sisi bertambah baik. Perbandingan keputusan
yang diukur dan dikira telah dijalankan menggunakan nisbah penurunan
tekanan dan keputusan menunjukkan bahawa keupayaan galas tanah
bawah dalam komposit kerak adalah bertambah baik. Kata kunci: Asas
komposit kerak tiruan; benteng disokong cerucuk; model ujian
pengemparan; penstabilan; tanah liat lembut
REFERENCES Ariyarathne, P. &
Liyanapathirana, D.S. 2015. Review of existing design methods
for geosynthetic-reinforced pile-supported embankments. Soils
and Foundations 55(1): 17-34. Blanc, M., Thorel, L.,
Girout, R. & Almeida, M. 2014. Geosynthetic reinforcement
of a granular load transfer platform above rigid inclusions:
Comparison between centrifuge testing and analytical modelling.
Geosynthetics International 21(1): 37-52. BS 8006. 2010. Code
of Practice for Strengthened/Reinforced Soils and Other Fills.
British Standard Institution, UK. Chen, R.P., Wang, Y.W.,
Ye, X.W., Bian, X.C. & Dong, X.P. 2016. Tensile force of
geogrids embedded in pile-supported reinforced embankment: A
full-scale experimental study. Geotextiles & Geomembranes
44(2): 157-169. Chen, R.P., Chen, Y.M.,
Han, J. & Xu, Z.Z. 2008. A theoretical solution for pile-supported
embankments on soft soils under one-dimensional compression.
Canadian Geotechnical Journal 45: 611-623. Erfen, H.F.W.S., Asis,
J., Abdullah, M., Musta, B., Tahir, S., Pungut, H. & Mohd
Husin, M.A.Y. 2017. Geochemical characterization of sediments
around Nukakatan Valley, Tambunan, Sabah. Geological Behavior
1(1): 13-15. Fagundes, D.F., Almeida,
M.S.S., Thorel, L. & Blanc, M. 2017. Load transfer mechanism
and deformation of reinforced piled embankments. Geotextiles
& Geomembranes 45(2): 1-10. Garnier, J., Gaudin,
C. & Springman, S.M. 2007. Catalogue of scaling laws and
similitude questions in geotechnical centrifuge modelling. International
Journal of Physical Modelling in Geotechnics 7(3): 1-23. Hewlett, W.J. &
Randolph, M.F. 1988. Analysis of piled embankments. Ground
Engineering 21(3): 12-18. Huang, J. & Han,
J. 2009. 3D coupled mechanical and hydraulic modeling of a geosynthetic-reinforced
deep mixed column-supported embankment. J. Geotextile Geomembr.
27(4): 272-280. Ishihara,
K. 1993. Liquefaction and flow failure during earthquakes. Géotechnique
43(3): 351-451. Ishikura, R., Yasufuku,
N. & Brown, M.J. 2016. An estimation method for predicting
final consolidation settlement of ground improved by floating
soil cement columns. Soils & Foundations 56(2): 213-227. Ishikura, R., Ochiai,
H., Yasufuku, N. & Omine, K. 2007. Estimation of the settlement
of improved ground with floating-type cement-treated columns.
Proceedings of the 4th International Conference on Soft Soil
Engineering, Vancouver. pp. 625-635. Jelisic, N. & Leppänen,
M. 2003. Mass stabilization of organic soils and soft clay.
Proceedings of the 3th International Conference on Grouting
and Ground Treatment, New Orleans, Louisiana. pp. 552-561. Liu, W., Qu, S., Zhang,
H. & Nie, Z. 2017. An integrated method for analyzing load
transfer in geosynthetic-reinforced and pile-supported embankment.
KSCE Journal of Civil Engineering 21(3): 687-702. Ng, C.W.W. 2014. The
state-of-the-art centrifuge modelling of geotechnical problems
at hkust. Journal of Zhejiang University-Science A 15(1):
1-21. Noor, M.J. & Ashraf,
M.A. 2017. Accumulation and tolerance of radiocesium in plants
and its impact on the environment. Environment Ecosystem
Science 1(1): 13-16. Rahman, M.M., Abdullah,
R.B., Wan Khadijah, W.E., Nakagawa, T. & Akashi, R. 2014.
Feed intake and growth performance of goats offered Napier grass
(Pennisetum purpureum) supplemented with concentrate
pellet and soya waste. Sains Malaysiana 43(7): 967-971. Sharma, J.S. & Bolton,
M.D. 1996. Centrifuge modelling of an embankment on soft clay
reinforced with a geogrid. Geotextiles & Geomembranes
14(1): 1-17. Stewart, M.E. &
Filz, G.M. 2014. Influence of clay compressibility on geosynthetic
loads in bridging layers for column-supported embankments. Geo-frontiers
Congress 156(130): 1-14. Taylor, R.N. 1995. Geotechnical
Centrifuge Technology. London: Blackie Academic and Professional. van Eekelen, S.J.M.,
Bezuijen, A. & van Tol, A.F. 2011. Analysis and modification
of the British Standard BS8006 for the design of piled embankments.
Geotextiles & Geomembranes 29(3): 345-359. Viswanadham, B.V.S.
& Mahajan, R. 2004. Modeling of geotextile reinforced highway
slopes in a geotechnical centrifuge. In Geotechnical Engineering
for Transportation Project, edited by Yegian, M.K. &
Kavazanjian, E. Proceedings of Geo-Trans. pp.637-646. White, D.J., Take, W.A.
& Bolton, M.D. 2003. Soil deformation measurement using
particle image velocimetry (PIV) and photogrammetry. Géotechnique
53(7): 619-631. Yao, M.Y., Zhou, S.H.
& Li, Y.C. 2004. Boundary effect analysis of centrifuge
test. Chin Q Mech. 25(2): 291-296. Yapage, N.N.S., Liyanapathirana,
D.S., Kelly, R.B., Poulos, H.G. & Leo, C.J. 2014. Numerical
modeling of an embankment over soft ground improved with deep
cement mixed columns: Case history. Journal of Geotechnical
& Geoenvironmental Engineering 140(11): 04014062. Zhang, L., Zhao, M.,
Hu, Y., Zhao, H. & Chen, B. 2012. Semi-analytical solutions
for geosynthetic-reinforced and pile-supported embankment. Computers
& Geotechnics 44(44): 167-175. Zheng, G., Jiang, Y.,
Han, J. & Liu, Y.F. 2011. Performance of cement-fly ash-gravel
pile-supported high-speed railway embankments over soft marine
clay. Marine Georesources & Geotechnology 29(2):
145-161. Zhuang, Y., Ellis, E.
&Yu, H.S. 2012. Three-dimensional finite-element analysis
of arching in a piled embankment. Géotechnique 62(12):
1127-1131. *Corresponding author; email: jiang101215@163.com
|
|||
|
