Application Research Of A New Type Displacement-screw Pile Foundation In Weihai

There is a common saying that every skyscraper is built from the ground.A very important premise in all kinds of architectural structures is the stable foundation.When the natural foundation can not meet the requirements of the settlement or bearing capacity of buildings and structures,the pile foundation in the foundation soil can be considered to improve the bearing capacity.The displacement-screw pile is a pile of small diameter,with high bearing capacity of single pile,large torque of construction piling machine and strong penetration.It is suitable for sand,silt,pebble layer,fully weathered rock,strong weathered rock and so on.It is also a new type of environmental protection pile without mud and residual soil in construction.Because of its rapid construction and low cost,it has been used in large quantities in Weihai.In this paper,through the physical model test method and the ADINA finite element dynamic numerical simulation method,the three-dimensional dynamic analysis of the three-dimensional particle flow of PFC3 D is applied.A comprehensive discussion on the physical and mechanical properties of the soil in the surrounding soil by the two-way spiral extruded drilling tools during the hole forming process.The mechanism of the hole forming of the rotary extruded bit and the evolution law of the soil particles in the side wall in the space contact form are studied.The compaction mechanism of the two-way spiral extrusion pile is obtained.Through the detection of displacement-screw pile pile under three different geomorphic unit in Weihai,Q-S curve analysis,and destructive test,we have come to a conclusion,which can check the design bearing capacity and guide practical construction.A large number of experimental data obtained from the Jiaodong Peninsula in Low Mountain hilly area erosion denudation monadnock piedmont plain small coastal geomorphic unit and front slopes of alluvial diluvial facies and swamp facies,landforms and quaternary alluvium geomorphic units,bidirectional spiral pile side resistance coefficient,increase the comprehensive value of pile tip resistance and pile tip resistance calculation this type of pile,the calculation in three different geomorphic units of the bearing capacity of single pile.It is applicable to most of the stratigraphic landforms in the Weihai area.Through the practical application of displacement-screw pile,summarize the appropriate stratum and proper equipment parameters to its great superiority.With the comparison of Long spiral cast-in-place pile,Post Grouting for Bored Pile in Slurry Wall and hand-excavated pile,there are some economic and social benefits,which lay the foundation for the promotion and application of the whole country.