Although self drilling anchor bolt
support has instant load, prestressing force,good support,low labor intesnsity, low cost of supporting and so on advantages, vigorously promoteing the technology of self drilling anchor bolt support is a effective way to realize high production and high efficiency in working face.But using the technology need to be aware of the following issues:
(1) The self drilling anchor bolt must make full use of prestressing force of itself, self drilling anchor bolt must be cling to the bottom of wall, otherwise self drilling anchor bolt won't be able to have the effect of reinforcement beams and composite beams.
(2) Keeping the roadway roof and two level off when excavating coal lane,the principle is that preferably without damaging the roof integrity and reducing the blasting vibration for coal, avoid roadway surrounding form stress concentration, to ensure the stability of the roadway.
(3)When decorated, the roof of self drilling anchor bolts are not all the vertical direction of roof, it should be subject to the radial shall prevail and gap with cement grouting full of broken rock clearance, make sure the self drilling anchor bolt to have sufficient anchorage.
(4)The self drilling anchor bolt must have a support structure and produce a certain amount of anchor force, without supporting force of anchor grouting anchor rope unable to form active support, and therefore cannot be used for supporting in coal roadway.
(5) With the widespread application of self drilling anchor bolt support technology, the recycling work of self drilling anchor bolt should also be give more attention ,although the value of a set of self drilling anchor bolt is not high, but add up, and brought about by the economic benefits will be substantial.