Impact analysis and macro-deformation control measures of TRD construction cement-soil mixing walls

TRD construction cement-soil mixing walls have been increasingly used in deep and large excavations. The TRD construction will disturb the soils around construction panels and hence influence the nearby facilities when it is used in urban areas. Field monitoring is carried out on lateral soil displacements and ground surface settlements during TRD construction in three projects, i.e., Hongqiao Business District-08 block (phase I), Shanghai Xisiwenli excavation on Xinzha Road, and Shanghai International Financial Center. Based on the field monitoring results, the impact of TRD construction on the nearby environment is systematically analyzed. It is shown that the overall influence of TRD construction on the nearby environment is small. Both the measured maximum ground surface settlement and lateral soil displacement are less than 10 mm in all the three cases. Moreover, the influence zone of TRD construction is within 10 m away from the panel. Some measures for minimizing the deformation during TRD construction are also proposed and discussed.