Technology of ecological bore locked pile for retaining and protecting for foundation excavation

In recent years, with the development of the highway industry, engineering waste soil and waste residue have not been effectively used, and environmental protection problems are becoming more and more serious. Based on the Suqian Avenue rapid transformation project and taking Happiness Road Tunnel foundation pit support as an example, this paper develops a new material, fluid soil, which has the characteristics of fluidity, low strength, self-compacting, low permeability, good stability, flexible strength control, and controllable curing time. The mud generated by the pile foundation can be used as the main material and processed into a mixture, solidified into a new type of geotechnical material (fluid soil) with a certain strength, water stability, low permeability, and long-term stability. Combined with the fact that the foundation pit support of this project is located under 110 kV high pressure and the headroom is only 19 m, two supporting construction technologies of ecological bore locked pile and ecological construction pile with low headroom rotary digging are summarized. It can be used as a reference for similar construction.