Improvement of metro shield muck to controlled low-strength material
Zhu Yuxing1,2 Bian Yi1,2 Min Fanlu1,2 Zhu Wei1,2
1. Key Laboratory of Geomechanics and Embankment Engineering, Hohai University, Ministry of Education, Nanjing 210098, China;
2. College of Civil Engineering and Transportation Engineering, Hohai University, Nanjing 210098, China
Abstract：Whether a large amount of slag generated by subway shield construction in China can be transformed into fluidized soil for use as a backfilling material for urban pipe corridor construction would be studied. Combined with the shield slag of Renjiazhuang-Wangfuzhuang section of Jinan Metro Line R2, indoor experiments were carried out. The fluidity, strength and influencing factors of slag-modified fluidized soil under different conditions were analyzed. The results show that, after the proper water-solid ratio and lime-sand ratio improved, the shielded slag used in this study met the requirements of pipe network backfilling. The best formula was the water-solid ratio of 0.5～ 0.53, lime-sand ratio 0.15. The fluidity of fluidized backfill soil was mainly affected by the water-solid ratio, and the strength was mainly controlled by the water-solid ratio. If both requirements were to be met, the formulation design should be based on the watercement ratio. To be fluidized backfilling material was a feasible direction to deal with the earth pressure balance shield muck of urban subway.
