Numerical calculation and experimental study of drilling shaft bottom in special thick alluvium;

Aiming at the status,that there is not theory reference for project determination of shaft line freezing in deep alluvium,in the paper a method which combines the finite element numerical simulation with multi-target gray situation decision-making was brought forward,in order to optimize project determination of deep shaft line freezing.

Concrete mixture ratio research of C80 HPC in extraordinary depth surface soil;

In order to reduce the thickness of shaft lining and increase its bearing capacity and endurance, high-strength and high-performance concrete (HSAHPC) is adopted to construct freezing shaft lining in extraordinary depth surface soil.

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.