[1] Liu Hanlong, Aly H. Mahfouz, Chen Yonghui, et al. Ground treatment of sea embankmentby vacuum preloading with PVDs [J]. Journal of Southeast University (English Edition), 2004, 20 (1): 96-101. [doi:10.3969/j.issn.1003-7985.2004.01.020]

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Ground treatment of sea embankmentby vacuum preloading with PVDs()

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Journal of Southeast University (English Edition)[ISSN:1003-7985/CN:32-1325/N]

Volumn:

20

Issue:

2004 1

Page:

96-101

Research Field:

Civil Engineering

Publishing date:

2004-03-30

Info

Title:

Ground treatment of sea embankmentby vacuum preloading with PVDs

Author(s):

Liu Hanlong¹;  Aly H. Mahfouz¹;  2;  Chen Yonghui¹

¹Geotechnical Institute, Hohai University, Nanjing 210098, China
²Geological and Geophysical Department of Engineering College, Suez Canal University, Suez, Egypt

Keywords:

soft soils;  vertical drains;  vacuum preloading;  embankment;  ground improvement

PACS:

TU472

DOI:

10.3969/j.issn.1003-7985.2004.01.020

Abstract:

Vacuum provides an alternative in reducing the length of preloading period for soft soil consolidation. In this method, soft clay foundation is preloaded by reducing the pore-water pressures through the application of vacuum pressure in combination with surcharge preloading. A full scale and fully instrumented test embankment was constructed. A drainage pattern system combined with 22 m prefabricated vertical drains(PVDs)length was used with triangular pattern of 1.2 m spacing. Among the foundation instrumentation, piezometers were installed in the foundation subsoil at varying depth to measure the pore-water pressures. After 6 months of vacuum pressure application at 80 kPa, the test embankments were raised to a maximum height of 5.5 m. The effect of vacuum preloading was investigated by the field conditions, maintaining higher vacuum pressures, and unloading vacuum. The results are demonstrated the efficiency of combined vacuum and surcharge preloading.

References:

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[11] Cognon J M, Juran J, Thevanayagam S. Vacuum consolidation technology — principles and field experi￣ence. vertical and horizontal deformation of embankments [J]. Geotechnical Special Publi￣cation, ASCE, 1994, 2(40): 1237-1248.
[12] TPEI vacuum preloading method to improve soft soils and case studies [R]. Tianjin: Tianjin Port Engineering Institute, 1995.
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Memo

Memo:

Biographies: Liu Hanlong(1964—), male, professor, hliu@jlonline.com; Aly H. Mahfouz(1967—), male, graduate, Egypt, ahmafouz@sina.com.

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