北京砂卵石地层盾构机选型与设计

The Lectotype and Design of Shield for Sandy Pebble Stratum in Beijing

盾构选型是盾构法隧道施工的核心与关键,以北京地铁八号线天桥～永定门外站区间为例,对北京地区砂卵石地层进行盾构选型.首先通过技术经济比选,确定选用加泥式土压平衡盾构,在此基础上,根据砂卵石地层的特点及盾构机械性能的适应性,对刀盘的形式,刀具布置及螺旋输送机、渣土改良系统、同步注浆系统及铰接机构等盾构机的二级系统进行了针对性的设计,保证盾构的正确选型,对类似地层条件下盾构选型具有一定的参考意义.

Shield lectotype is the core and key of the shield tunnel construction. Taking the section fi＇om Sky Bridge to outside of Yongding gate of Beijing metro line 8 as an example, the lectotype and design of shield machine for sandy pebble stratum in Beijing was carried out. Firstly, the earth-pressure balanced shield was adopted through the technical and economic comparison. Then, according to the characteristics of the sandy pebble stratum, the cutters were arranged and the secondary systems of shield including screw conveyor, the dregs improvement system, synchronous grouting system and articulated bodies were designed. This paper has certain reference value for the shield lectotype in the similar stratum.