Advantages of self drilling hollow anchor bolts used as soil nails
by Anna S. Optimization SpecialistSoil nailing is currently an important technology for reinforcing
slopes such as mountains, dams, and building foundations. However, the
traditional technology is to drill holes first, and then anchor bars are
embedded in the holes and grouted and fixed. The construction process not only
faces problems of high construction difficulty, low work efficiency, and high
cost but also face the problem of poor connection stability
between soil nails and geological structures. In recent years, self-drilling hollow anchor bolts have been
widely used in soil nail support due to their simple construction technology
and good anchoring effect. Today I will introduce the advantages of hollow soil nails.
What
are self-drilling hollow anchor bolts?
Self-drilling hollow anchor
bolts are composed of a hollow anchor bar, nut, plate, coupler, centralizer,
and drill bit. It can combine drilling, grouting, and anchoring functions
together. Without using casing pipe, it can greatly improve the construction
efficiency and shorten the construction cost.
Construction
process
1. Preparation work. Check
whether the functions of the drilling rig are normal, whether the drill bit and
anchor rod are damaged, and whether the rod body is unblocked, etc. After
making sure that there is no problem, screw the hollow anchor bar to the drill
bit.
2. Drill and grout. Connect
anchor rod and grouting pipe to the drilling rig through a rotary grouting
adapter, and simultaneously drilling and grouting.
3. Coupler anchor rod. If a
single anchor rod can’t reach the designed drilling depth, a coupler can be
used to meet the design requirements.
4. Installation of the plate
and nut. After grouting, install a plate and nut close to the construction
surface to ensure the anchoring effect.
5. Field test. After the
installation is completed, the self-drilling anchor rod is tested for its
pull-out force to check whether it meets the design requirements.
Advantages
Traditional soil nail is
installing solid steel bars into pre-drilled holes and then grouted and anchored.
Compared to traditional soil nails, What are the advantages of
self-drilling hollow soil nails?
1. In loose or easily collapsed
geological conditions, no casing is needed. Therefore, when installing soil
nails, most of the drilling rigs are small and can well cope with slopes and
narrow spaces.
2. Simultaneous drilling and
grouting process can increase the grout body diameter and maximize the sheer
force of the grout body/soil interface.
3. Simultaneous drilling and
grouting process is less vibrating, which effectively reduces the interference
to the surrounding soil.
4. The installation speed of
hollow soil nails is twice that of solid soil nails thanks to the construction
technology.
5. Can replace the concrete
retaining wall.
6. High-pressure grouting
process can inject the cement grout into the loose stratum, greatly increasing
the grout diameter and its friction force, and the anchoring quality is better
than that of solid soil nails.
Through the introduction, we
know that self-drilling hollow anchor bolts used as soil nail is an efficient
and economical ground support method, which can control and improve the soil's
natural stability. is currently an important technology for reinforcing
slopes such as mountains, dams, and building foundations. However, the
traditional technology is to drill holes first, and then anchor bars are
embedded in the holes and grouted and fixed. The construction process not only
faces problems of high construction difficulty, low work efficiency, and high
cost but also face the problem of poor connection stability
between soil nails and geological structures. In recent years, self-drilling hollow anchor bolts have been
widely used in soil nail support due to their simple construction technology
and good anchoring effect. Today I will introduce the advantages of hollow soil nails.
What
are self-drilling hollow anchor bolts?
Self-drilling hollow anchor
bolts are composed of a hollow anchor bar, nut, plate, coupler, centralizer,
and drill bit. It can combine drilling, grouting, and anchoring functions
together. Without using casing pipe, it can greatly improve the construction
efficiency and shorten the construction cost.
Construction
process
1. Preparation work. Check
whether the functions of the drilling rig are normal, whether the drill bit and
anchor rod are damaged, and whether the rod body is unblocked, etc. After
making sure that there is no problem, screw the hollow anchor bar to the drill
bit.
2. Drill and grout. Connect
anchor rod and grouting pipe to the drilling rig through a rotary grouting
adapter, and simultaneously drilling and grouting.
3. Coupler anchor rod. If a
single anchor rod can’t reach the designed drilling depth, a coupler can be
used to meet the design requirements.
4. Installation of the plate
and nut. After grouting, install a plate and nut close to the construction
surface to ensure the anchoring effect.
5. Field test. After the
installation is completed, the self-drilling anchor rod is tested for its
pull-out force to check whether it meets the design requirements.
Advantages
Traditional soil nail is
installing solid steel bars into pre-drilled holes and then grouted and anchored.
Compared to traditional soil nails, What are the advantages of
self-drilling hollow soil nails?
1. In loose or easily collapsed
geological conditions, no casing is needed. Therefore, when installing soil
nails, most of the drilling rigs are small and can well cope with slopes and
narrow spaces.
2. Simultaneous drilling and
grouting process can increase the grout body diameter and maximize the sheer
force of the grout body/soil interface.
3. Simultaneous drilling and
grouting process is less vibrating, which effectively reduces the interference
to the surrounding soil.
4. The installation speed of
hollow soil nails is twice that of solid soil nails thanks to the construction
technology.
5. Can replace the concrete
retaining wall.
6. High-pressure grouting
process can inject the cement grout into the loose stratum, greatly increasing
the grout diameter and its friction force, and the anchoring quality is better
than that of solid soil nails.
Through the introduction, we
know that self-drilling hollow anchor bolts used as soil nail is an efficient
and economical ground support method, which can control and improve the soil's
natural stability.
Sponsor Ads
Created on Nov 9th 2021 20:51. Viewed 257 times.