[1] Ali H.Mahfouz, Liu Hanlong, C.F.Chiu, et al. Laboratory study for effects of vacuum preloadingon physical and mechanical properties of soft clayey soils [J]. Journal of Southeast University (English Edition), 2005, 21 (1): 82-87. [doi:10.3969/j.issn.1003-7985.2005.01.018]
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Laboratory study for effects of vacuum preloadingon physical and mechanical properties of soft clayey soils(
)
真空预压技术对软粘土物理与力学属性影响的试验研究
)Journal of Southeast University (English Edition)[ISSN:1003-7985/CN:32-1325/N]
- Volumn:
- 21
- Issue:
- 2005 1
- Page:
- 82-87
- Research Field:
- Civil Engineering
- Publishing date:
- 2005-03-30
Info
- Title:
- Laboratory study for effects of vacuum preloadingon physical and mechanical properties of soft clayey soils
- 真空预压技术对软粘土物理与力学属性影响的试验研究
- Author(s):
- Ali H.Mahfouz1; 2; Liu Hanlong; C.F.Chiu1; Gao Yufeng1; Zhang Xiuyong1; 3
-
1Geotechnical Institute, Hohai University, Nanjing 210098, China
2Geological and Geophysical Department of Engineering College, Suez Canal University, Suez, Egypt
3Yellow River Jinan Bureau, Jinan 250013, China
- Ali H.Mahfouz1; 2; 刘汉龙1; 赵仲辉1; 高玉峰1; 张秀勇1; 3
- 1河海大学岩土工程研究所, 南京 210098; 2苏伊士运河大学工学院地质与地球物理糸, 埃及苏伊士; 3济南市黄河河务局, 济南 250013
- Keywords:
- soft soil; vacuum preloading; consolidation; permeability; strength
- PACS:
- TU472
- DOI:
- 10.3969/j.issn.1003-7985.2005.01.018
- Abstract:
- A new triaxial apparatus was designed and manufactured.It is able to apply surcharge and combined vacuum-surcharge pressures on soil samples, and allows for monitoring of excess pore-water pressure, axial strain or settlement, and volumetric strain during the process of consolidation.Tests were performed using the apparatus on undisturbed soft clayey soil samples, which were collected from Wenzhou, Zhejiang Province, China, at average natural water content 72.5%.The consolidation behavior of the clay has no rigorous difference, whether it is consolidated under the vacuum, surcharge, or combined vacuum-surcharge preloading.The study shows that some physical properties of the soft clayey soils are changed and mechanical properties are improved to support excessive loads transferred to the soil foundation due to construction.
- 研制了一套新三轴试验仪, 该仪器能将堆载和真空加载在土样上, 在固结进行中能同时监控超孔隙水压力、轴向应变(沉降)与体积应变.并根据浙江省温州市原状软粘土进行了固结试验, 软粘土的天然含水率是72.5%.试验结果发现, 真空预压、堆载预压或真空-堆载联合预压3类加固方式中, 粘土的固结特性没有明显差异.研究表明3种加固方法改变了软土的一些物理属性并改善了它的力学属性.
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Memo
- Memo:
- Biographies: Ali H.Mahfouz(1967—), male, graduate, Egyptian, ahmahfouz@hotmail.com;Liu Hanlong(corresponding author), male, doctor, professor, hliu@hhu.edu.cn.