On the factors influenced the wall cracking of vertical shaft in alluvium and its preventive technique;

The present high pressure experimental research and analysis of undisturbed deep soil indicate that the static earth pressure of thick overburden is considerable different from that of superficial soil.

Based on the condition of Banji Coal Mine, this paper discusses the selection of shaft sinking techniques through thick overburden, and according to the concerned latest specifications, proposes the designing method of reinforced concrete wall and composite wall with steel plate and concrete in shaft drilling.

This paper summarizes the new freezing technology used in construction of the auxiliary shaft of Longgu Colliery in thick overburden.

Development and prospect of research on artificial freezing method of shaft sinking technology in deep alluvium;

In view of the background that our country will construct large-scale collieries in deep alluvium area, the key technologies which required in the freezing process to be used in the deep shaft are research of the basic theory of frozen soil for deep alluvium,designs of freeze wall and shaft lining structure that suitable for the deep alluvium,and the construction technology of freezin.

The aims of this paper is to solve the problems of sedimentation of deep alluvium because of water loss and longitudinal compression failure in composite shaft lining, and then equicohesively repair it.

In order to ascertain a reasonable strip mining project for the coal mining under villages with thin bedrocks under the thick alluvium in Linhuan, the characters of surface subsidence in strip mining were studied by numerical simulation method based on discrete element.

The new freezing technology and the new freezing design method used in construction of the auxiliary shaft of Longgu Colliery that its freezing deepness is the first exceed 600 m in thick alluvium.

According to the characteristic of Liangbaosi mine, the author summarized experiences and methods to operate and construct by freezing the thick alluvium, also discussed the methods to freeze the thick alluvium (600m) and construct.