Anchor used: Removable Ground Anchor
The pit is supported by cast-in-place piles and compressive stress-dispersive underreamed anchor. Among them, 308 anchor bolts are used, which has length 26m each. With the implementation of this method, about 10 million RMB is saved up from this project. In addition, the construction period is shortened for two months. The end bearing capacity of the underreamed anchor has 30%-50% pull-out force greater than the original anchor. Underreamed anchor of about 7 meters below the river channel can still achieve the 810kN pull-out force.
Due to the unique force principle of the underreamed anchor, we use the compressive stress-dispersive underreamed anchor by jet grouting technology to solve the problems of low pullout force, instability, soil disturbance, and tendency of the occurrence of road settlement. Meanwhile, we replace the use of conventional anchor with hot melt removable ground anchor to solve the recovering problem. All in all, the construction work is reliable and does not cause serious road settlement.
Pit area: 31000m2
Excavation depth: 9.6～10.4m