Axial pull-out test of core concrete of prestressed concrete pipe piles and analysis of stress at the pile end;

The paper introduced the design and construction of pile end bearing layer strengthening for assuring the engineering quality.

The bearing capacity of super-long and large-diameter bored pile tip is influenced by the facts including construction process,depth effect,size effect and so on.

The analysis of pile tip settlement measuring and the data of pile testing,has ex-pressed that the stress-strain process of upper loads on pile shaft and foundation soil has elastic deformation characteristics of both pile and foundation soil.

Research on torsional dynamic impedance of end-bearing pile in layered soils;

Application of super short end-bearing pile on the soft foundation in old pit;

In order to proof bearing capacity of single pile and find out friction resistance around pile and pile base resistance,the load transfer and resistance analysis test of end-bearing pile are taken by using the load and strain test of drilling hole perfusion end-bearing pile and the cyclic loading method.

5 m thick soil filling can make negative skin friction most be developed,and the bearing capacity of frictional pile as well as end-bearing pile under negative sk.

An academic study on the bearing capacity of end-bearing piles is carried out in the paper.