【作者】 刘德智； 雷金山； 杨秀竹；

【Author】 Liu Dezhi,Lei Jinshan,Yang Xiuzhu Guangzhou Metro Corporation, 510380,Guangzhou,China

【机构】 广州市地下铁道总公司； 中南大学土木建筑学院；

【摘要】 盾构机在密实性差、富水性和渗透性强、承载力较低的全断面淤泥质粉细砂层中掘进时,易产生喷涌,并造成地表沉降。结合广州轨道交通6号线"大坦沙—黄沙"区间盾构工程实例,探讨盾构机在采用双级螺旋输送机后,通过控制密封仓内土压力,以达到有效控制变形、避免地面塌陷的目的;并总结了土压平衡式盾构穿越富水砂层时,采用的主要施工技术和措施。更多还原

【Abstract】 Guangzhou Metro Line 6 is partially located in silty fine sand,which is incompact,rich in water,and has strong permeability and low bearing capability.When tunneling in this section,it is easy to bring about gush of water and sand,resulting in earth’s surface settlement.In line 6 engineering,a two-stage helical conveyer is used to control this phenomenon.First,the two-stage dregs outlet of helical conveyer is turned off to prevent water and sand from rushing forth,then macromolecule polyer or bentonite clay are injected into the earth cabin and the front-end of helical conveyer in order to keep the cabin pressure.Secondly, drain outlet of the second stage helical conveyer is turned on and the water seepage drained,then the second stage helical conveyer will eject the dregs.Finally,dregs outlet of the first stage helical conveyer is turned on to eject the dregs in the earth cabin.Two-stage helical conveyer is used successfully in tunneling the section from Datansha to Ruyifang of Guangzhou Metro Line 6.更多还原