泡沫改良富水砂层工程性质的实验研究  

Study on Engineering Properties of Foam-conditioned Water-soaked Sand Strata

作　　者：乔国刚[1] 陶龙光[1] 刘波[1] 郭永浩[1] 

机构地区：[1]中国矿业大学力学与建筑工程学院,北京100083

出　　处：《现代隧道技术》2009年第6期79-84,共6页Modern Tunnelling Technology

基　　金：国家自然科学基金(50674095);教育部博士点基金(20060290014)资助

摘　　要：土压平衡盾构穿越复杂地层时,必须采取土体改良措施,目前泡沫改良土体已被广泛应用于盾构施工中。我国地铁施工中所用泡沫剂多为进口产品,国内产品因质量原因采用很少。利用自行研制的泡沫剂开展泡沫对细砂、粗砂土性改良的试验研究表明,泡沫不但能显著降低砂土的渗透系数和剪切强度,而且能大大增强土的压缩性;若加入适量膨润土或粘土,则可获得进一步提高砂土保水性、流动性及进一步降低砂土的渗透系数和剪切强度的效果,这对盾构施工中改良土体工程性质的研究具有重要意义。Soil improvement measures must be taken for earth pressure balanced shields driving in complex strata and at present foam-conditioned soils have been widely used in shield tunneling. In China, most of the foam agents used in subway construction are imported products while domestic products are rarely applied because of quality reasons. In this paper, a self-developed foam agent was used to carry out test research on soil property improvement for fine sand and coarse sand. Conclusions are drawn that foam can not only reduce the permeability coefficient and the shear strength of sand significantly, but also enhance the compressibility of it greatly; if appropriate quantity of bentonite or clay are added in the sand, the water-holding capacity and liquidity of the sand will be further enhanced and the permeability coefficient and shear strength of sand will be further reduced. This is extremely favorable to improve the engineering properties of soil in shield tunneling.

关 键 词：泡沫 土体改良 EPB盾构 隧道施工 

分 类 号：U455.43[建筑科学—桥梁与隧道工程]