Soil Nailing Supporting In foundation pit excavation

With the speeding up of urbanization, all kinds of civil construction and public transportation infrastructure increases rapidly, the development and utilization of underground space is increasing in the city, and some of the engineering construction approaches for high power tower.

The foundation pit excavation in underground engineering construction is easy to cause deformation of soil, leading to differential settlement of the power tower, which will lead to the overall stability of the transmission tower and large
transmission security hidden danger, even catastrophic consequences.

One power steel tower is near the new municipal engineering excavation. The excavation depth of pit is about 9.0m under natural ground. Due to urgency and narrowly limited time schedule, the tower should be protected when foundation pit excavation.The tower foundation generally designed with four independent shallow foundation, two basic tensile, compression of the other two bases.

For guarantee the stability of the foundation pit,composite soil nailing can be performed conveniently.

However the deformation of the slope is large when the tower near the pit and induce damages to the steel tower. So the paper take advantage of micro steel pipe pile technology of underpinning reinforcement as supplementary of composite soil nailing supporting.

The combination of composite soil nailing and piles of foundation underpinning worked better for pit excavation with protection of power tower and provides a reliable technical reference.