By using the combined support technology of concrete sprayed anchored net,anchorage cable and backwall grouting in the mechanical and electronic underground chamber of Shuangmiao extending area of Gedian Mine,Shenhuo Coal and Electricity Joint-stock Company,the tunnel condition is effectively improved,the deformation of the surrounding rock is inhibited.

This paper introduced backwall grouting process and grouting effect of-290 level downcast shaft in Jilongshan Gold Mine.

Test and Application of GPR Detecting of Grouting Behind Segment of the Shield Tunnel Across the River;

When we use the ground penetrating radar(GPR) to detect the effect of grouting behind segment at the shield tunnel tail,it is very important to ascertain the velocity of electromagnetic wave(EMW) to obtain accurate results.

And the grouting behind segment at the tail is more focused on for controlling the surface settlement.

Utilizing the self-made element model devices of backfill grouting,the change laws of grout deformation and grout pressure dissipation are studied under different grouting pressures,different grout material mixtures and different soil conditions.

During the construction with shield machine, backfill grouting is a necessary and key procedure, which can actively control stratum displacement and ground-stress release by filling the shield tail void, and thus reduce surround soil displacement and surface settlement.

Reuse of excavated fine sand for back grouting of shield tunnelling;

Based on the above consideration,the main subject of research is that how the discharged fine sand can be reused in the aspect of back grouting,and after the reuse of the fine sand,the back grouting recipe should be regulated in time with the change of .

The key technology of chemical grouting by breaking the wall to prevent leakage are the followings: choosing the chemical material, determining the grouting pressure, estimating the diffusion radius of grouting liquids, arranging grouting holes and calculating the grouting quantity.