岩石力学与工程学报
巖石力學與工程學報
암석역학여공정학보
CHINESE JOURNAL OF ROCK MECHANICS AND ENGINEERING
2013年
z1期
2692-2697
,共6页
土力学%软土%宏微观%真空预压%固结
土力學%軟土%宏微觀%真空預壓%固結
토역학%연토%굉미관%진공예압%고결
soil mechanics%soft soil%micro and macro%vacuum preloading%consolidation
地基处理前分析软土宏微观性质对预测真空预压法处理的有效性具有重要意义.通过室内宏微观试验,对珠海金湾地区软土矿物成分、比表面积,以及固结前后的微观结构、孔隙特征等进行分析和研究,得出土体结合水量、强度指标等影响真空预压法处理效果的关键因素.研究结果表明,珠海金湾软土黏土矿物成分含量不高,且黏胶粒占50%,比表面积较黏土矿物小;颗粒呈曲片絮凝状叠聚体,固结变形后出现团聚现象,孔隙压密,无颗粒破碎形状变化;微孔隙尺寸分布主要为400 nm<r<2500 nm,固结后试样的累积进汞量大幅减小,且大孔隙变成小孔隙.说明土体的结合水量不高,含较多的自由水,且内摩擦角变化不大,而黏聚力有较大的增长,真空预压法处理效果明显.
地基處理前分析軟土宏微觀性質對預測真空預壓法處理的有效性具有重要意義.通過室內宏微觀試驗,對珠海金灣地區軟土礦物成分、比錶麵積,以及固結前後的微觀結構、孔隙特徵等進行分析和研究,得齣土體結閤水量、彊度指標等影響真空預壓法處理效果的關鍵因素.研究結果錶明,珠海金灣軟土黏土礦物成分含量不高,且黏膠粒佔50%,比錶麵積較黏土礦物小;顆粒呈麯片絮凝狀疊聚體,固結變形後齣現糰聚現象,孔隙壓密,無顆粒破碎形狀變化;微孔隙呎吋分佈主要為400 nm<r<2500 nm,固結後試樣的纍積進汞量大幅減小,且大孔隙變成小孔隙.說明土體的結閤水量不高,含較多的自由水,且內摩抆角變化不大,而黏聚力有較大的增長,真空預壓法處理效果明顯.
지기처리전분석연토굉미관성질대예측진공예압법처리적유효성구유중요의의.통과실내굉미관시험,대주해금만지구연토광물성분、비표면적,이급고결전후적미관결구、공극특정등진행분석화연구,득출토체결합수량、강도지표등영향진공예압법처리효과적관건인소.연구결과표명,주해금만연토점토광물성분함량불고,차점효립점50%,비표면적교점토광물소;과립정곡편서응상첩취체,고결변형후출현단취현상,공극압밀,무과립파쇄형상변화;미공극척촌분포주요위400 nm<r<2500 nm,고결후시양적루적진홍량대폭감소,차대공극변성소공극.설명토체적결합수량불고,함교다적자유수,차내마찰각변화불대,이점취력유교대적증장,진공예압법처리효과명현.
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.