Combined on high stress and big deformation entry,metal articulated single beam and cross-articulated beam were used with combination,it was analyzed from designed craft and result,and a good experience was raised for spreading metal articulated beam in forepoling of entry.

Starting from the engineering practice,this paper probes into the principles,applicable conditions and construction processes of several forepoling technologies,and introduces the forepoling technology for the tunneling works.

The application of large-pipe-shed in advanced support in tunnel construction;

In the light of the phenomenon such as flowing sand,and sand boil subjected from the flowing sand stratum,in the construction of artificial digging piles,the advanced support with rein- foreement and the chemical churning pile technology can be used to form the watertight curtain,thereby preventing successfully the loss of san.