Application of Screw Anchor Pile Reaction Force Method in Static Load Test

Screw pile is a new type of pile with high bearing capacity, simple construction, low cost and recyclable. In the geotechnical engineering testing technology, the stowage method is more expensive and less efficient than the anchor pile method. Screw anchor pile reaction device, which uses screw pile as anchor pile to provide reaction force, has many advantages such as prefabricated construction, high pulling capacity and great development potential. In this paper, a project in the Guangzhou Nansha development zone is selected. Considering the special geology of thick silt soil, two methods of linking anchor piles and steel beams are adopted using the pick-up anchor pile reaction method and the tension-type anchor pile reaction method. A single pile vertical compressive static load test of an engineering test pile was carried out using a steel screw as an anchor pile. The results show that under the geological conditions with thick silt layer, the static load test by the pick-up anchor pile reaction method and the tension-type anchor pile reaction method can meet the specification requirements, and the testing effect is good. The φ400 steel screw pile is used in combination with the tooth drill bit, the soil has the strongest penetration capacity and the deepest burial depth, which can be used as the best pile type in the static load test of anti-anchor method; The tension-type anchor pile reaction method can effectively solve the problem of the low bending force of the main beam in the static load test. The pick-up anchor pile reaction method and tension-type anchor pile reaction method have a good promotion prospect in areas with poor geological conditions. And the results of this paper provide guidance for the design and application of the screw anchor pile reaction method in the static load test of the foundation pile.