To counter the technical problems met in Fuzhou Huaneng Power Plant 2nd－ phase coal terminal engineering such as deep－ trench rubble filling, artificial sand foundation, precast and installation of large case box, as well as inner embedding of large reinforced concrete pipe piles, etc.

A new method for calculating displacement of riprap in river harness;

Calculation of Drift Distance for Hydrodynamic riprap;

Several problems of scour protection by riprap bank;

After studying the characteristics of drifting, classification, erosion resisting of rock riprap by combining flume experiment and field measurement, this paper presents a better way of rock riprap and a type of protecting the riverbed which can not only improve the stabilization of the seawall, but also save the investments of the project.

By summarzing the construction experiences of section coal bin in Guhanshan coal mine,the authors have put forword the cutting explosive method of discarding cinder in deep*.

The effects of different machining parameters and structure parameters to fin height and groove depth are analyzed.

For rectangular gratings the task of controlling groove profile is simplified to controlling the duty cycle and groove depth.

This paper built theoretic model between the liquid crystal and the equivalent regular grating,and calculated theoretic data of the zero order diffractive efficiency and groove depth h.