土压平衡盾构施工过程中 ,土压室内的土料起着平衡开挖面的水、土压力 ,支撑开挖面的作用。因此这种土料须具有良好的塑性变形、软稠度、内摩擦角小及渗透率小等。一般施工路线的土质不能完全满足这些特性 ,所以要进行土壤改良。常用的土壤改良剂为水、膨润土、粘土和化学泡沫 Earth pressure balance Shield construction process, earth pressure soil material plays a balance of excavation surface water, earth pressure, supporting the role of excavation surface. Therefore, this material must have good plastic deformation, soft consistency, small internal friction angle and permeability and so on. The soil quality of the general construction route can not fully meet these characteristics, so soil improvement is needed. Common soil amendments are water, bentonite, clay and chemical foams