Hollow anchor bar is a kind of multi-functional anchor bar. It can unify operations of drilling, grouting, and anchoring and has more anchoring effect in complex soil stratums.
There is a water intake slope, because of weathering effect,the upper part crushed, topsoil slipped, and drill pipes could not work. After exploration survey, the whole slope is stable, while there are unstable rock blocks and consequent landslide backfall at the partial structural plane. So hollow anchor bar is used in this construction. The length of hollow anchor bar should be 6m, distance between anchors is 1.5m*1.5m, dip angle is 20°, mesh reinforcement on the surface of slope should be 20cm*20cm. Concrete should be type of C25 with the thickness of 15cm.
Build an access road for down-the-hole drill, the width of access road should be 3m, the gradient of the slope can not be over 30%, site of construction should be 4m*5m. Sign the position of drilling hole and then start to drill. According to geological condition, fix the drilling angle. Put special shank adapter on down-the-hole drill, connect hollow anchor bar and shank adapter. The speed of drilling should be controlled to reduce impact times. After drilling, drilling hole should be cleaned by air pressure. Dismantle the drilling rig, let one side of hollow anchor bar can be seen, connect this side with grouting pump, pulse on mortar mixer, put slurry into it and mix water to stir uniformly.Control water flowmetre to make water cement ratio of slurry to be 0.4~0.5. When grouting pressure is the designed value, we can stop grouting.