Based on the practical status of the construction joints for the culverts of the permanent lock of TGP, the design of hole arrangement of chemical grouting was optimized theoretically. The traditional grouting equipment and the grouting technique were improved. By means of adopting CW epoxy grouting agent developed by Yangtze River Scientific Research Institute, and the horizontal deep hole, higher pressure, durable, twin order and multi-holes co-grouting technique, using the pneumatic automatic electronic chemical grouting system, the chemical grouting treatment for cold joints was performed. The hydraulic pressure test result showed that after grouting the splitting tensile strength reached the requirements of design.