In this article,the author concludes and analyzes study and application situations of tapered piles,and points out that the tapered pile is an advanced pile shape and is worth to be applied widely.

This thesis carries out some studies on the service behavior of the tapered pile and its mechanical properties in different soil layers, including the analyses of the theoretic bearing capacity and settlement, the field experiment results and analysis of economical effectiveness of the tapered pile.

Nowadays though the theory of tapered pile has been studied for almost 30 years,it is not universally used and aroused enough attention,which is due to the study on its bearing mechanism and characteristics have not deep understand as compared to the theory of uniform-section pile.

In order to probe into the feasibility of using wedge piles in Tianjin area,this paper studies the law of the variation of ultimate vertical bearing capacity,shaft resistance and tip resistance of a wedge pile by compressive loading on the top.

Camber calculating model and simulation of wedge strip in rolling;

Excessive convexity,severe wedge,dissymmetric convexity and partial protrusion will result in sticking of sheets during annealing in the bell-type furnace.

Designed one kind of two stage wedge-type polarization independent optical isolator is designed.