MACRO AND MICRO ANALYSES OF EFFECTIVENESS BY VACUUM PRELOADING TREATMENT OF SOFT SOIL
MO Haihong1，2，WANG Jing1，2，LIN Yixi3
(1. School of Civil Engineering and Transportation，South China University of Technology，Guangzhou，Guangdong 510641，China；2. State Key Laboratory of Subtropical Building Science，South China University of Technology，Guangzhou，Guangdong 510641，China；3. Zhuhai Municipal Construction Engineering Quality Supervision and Test Station，Zhuhai，Guangdong 519015，China)
Abstract：The macro and micro analyses of soft soil before foundation treatment are important to predict the effectiveness of vacuum preloading treatment. Through the laboratory macro and micro tests，the properties of soft soil from Zhuhai Jinwan area are investigated，including mineral composition，specific surface area，microstructure，pore properties before and after consolidation，etc.. The key factors are concluded which indicate vacuum preloading treatment effect，such as amount of bound water，strength index. Research result shows that clay content of soft soil from Zhuhai Jinwan area is not high，with the clay content about 50%；and specific surface area is small. The soft soil grains are curved flocculation polymer. After consolidation，microscopic structure has noticeably aggregated with compactness and no particle breaking. The micro-pore distribution is mainly between 400 and 2 500 nm. The cumulative intrusions sharply decrease after consolidation，and pores turn smaller. Therefore，the amount of bound water is not high with more free water. The change of internal friction angle is not big，and cohesion has larger growth. It shows good availability of the vacuum preloading method in soft soil from Zhuhai Jinwan area.
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2013, Vol. 32 
