Hollow bar anchor can be used as drill rod and grouting rod at the same time. During
hydropower station, it can be used to support slope and diversion tunnel, which has
functions of stabilization, reinforcement and deformation prevention.
Hollow bar anchor is widely used in foundation pit support engineering recent years. It can
combine drilling, grouting and anchoring together, time-saving and high-efficient. In
addition, during the construction, there is no shake, no noise and no deformation
phenomenon, it has little influence for surrounding environment. After its installation, the
intensity of wall is strong, stiffness is big and supporting stability is good.
Generally speaking, hollow bar anchor is suitable for all the strata that retaining wall and
soil nail wall and also the prestressed cable bolt can apply to .

For the anchoring technology which has drilling operation requirements, drilling is usually
the most critical process and directly affect the bearing capacity of the hollow bar.
Drilling in the loose stratum or the stratum with groundwater, there is severe hole collapse
phenomenon so that it’s necessary to add the casing to match. The use of casing can improve
drilling progress, but have adverse effect on the bond between the mortar and the hole wall
and meanwhile increase the difficulty and cost of construction.

While hollow bar anchor applies very well for pebbles and boulders stratum. The disturbance
part of surrounding rocks can be effectively reinforced through grouting and then the
anchorage area will be enlarged. If water leakage appears during the drilling process, the
method of blowing cement powder with a high-pressure wind to the hole can form a temporary
wall around the drill hole so as to reduce the hole collapse phenomenon.