1. According to the topographic and geological conditions, determine the drilling angle;
2. Three methods of hollow anchor bar installation: rotation installation, impact installation and rotating impact installation. It should be avoided to increase the speed of drilling blindly just for improving the construction efficiency. The speed should be controlled reasonably for less shocks and more rotation, which can prevent the water hole on the drill bit of hollow anchor bar blocked by the drilling cuttings. If the water hole was blocked, the hollow anchor bar should be moved in and out about 50cm repeatedly to make the hole clean.
3. Using number value of air pressure to test whether the hollow anchor bar is smooth and the grouting material is uniform and continuous.
4. Observe the pressure gauge when grouting. If the pressure reached the standard and both grouting material consistency of pouring out and injecting in are the same, the grouting is finished.