During the construction of the hollow grouting anchor, what are the key points for the construction personnel to control the quality of work?
1. Construction preparation
①Inspect the feng shui, electricity, and equipment pipelines, and test run them to ensure they are in condition. ②The on-site anchor rod meets the requirements. ③Operators wear personal protective equipment. ④Inspect the surrounding rock on site before construction.
2. Measurement positioning
According to the design requirements, determine the anchor hole position and make a mark. The allowable deviation of the hole position is ±100mm.
3. Drilling and installation
① Check whether the water hole of the bolt body drill bit is unblocked, and if there is any blockage, clean it in time. ②The anchor rod is aligned with the hole position and drilled slowly until the design depth. Keep the exposed length of the anchor rod at 10-15cm.
4. Clean up inspection
①After the anchor rod is drilled into the design depth, wash the hole with water and high pressure air.
②Check whether the bolt spacing, length, and angle meet the requirements, and discard the re-drill if it is unqualified.
5. Bolt grouting
①When preparing the slurry, the operator should wear rubber gloves, goggles, and long rubber shoes. ②The grouting material is poured in through the middle hole of the rod. The upward hole should be equipped with stop plug and vent hole as required, and the grouting pressure should be controlled according to the technical requirements. ③The grouting shall be carried out in staggered and spaced intervals. After the grouting is finished, the effect shall be checked. If the grouting is unqualified, grouting shall be added. ④When grouting, workers are not allowed to stand near the grouting port.
①The installation quantity meets the requirements, and the penetration length of the anchor rod is not less than 95% of the design. ②The backing plate nut can be tightened after the cement paste strength reaches 10.0MPa, and the anchoring rod backing plate is closely attached to the sprayed concrete surface