Self drilling hollow bar is an effective supporting method. It can adopt various kinds of steel tube, as for material of hollow bar anchors, there are basic requirements.
1. High strength.
The higher of self drilling hollow anchor’s tension, the smaller of prestressing force’s loss ratio.
2. Better plasticity and processing performance.
Ground is the foundation of building projects, it bears the weight of whole architectural structure, its construction quality directly relates to normal operation and quality problem. To ensure construction quality and use quality of building projects, it should start from foundation and reinforcement technology to enhance ground’s stability and quality, then promote healthy development of building career.
There are many factors influencing slope stability, which can be generalized in internal and external factors.
Self drilling hollow anchor needs to keep prestress for a long time, it’s optimal that self drilling anchor has high strength, at the same time, it has little relaxation losses, which demands prestressing tendon has enough plasticity. During construction, prestressing tendon can produce bend inevitably and will get higher local stress.
Sinorock can offer a design service for all types of ground anchors (rock bolts and soil nails) including; High Capacity, Bar anchors and Hollow threadbar anchors.
Hollow bar anchors are similar to self drillers. We have designed many projects using this technique particularly where a rapid solution in unstable soils is an important aspect.
Self-drilling hollow bar methods are also used, involving a hollow anchor bar, a sacrificial bit with ports, and an external full depth or partial depth casing as needed to control overburden soils. In this case grout is pressurized down through the hollow bar, out the grout ports and a pressure head is maintained such that the annulus in the soil around the bar is pressurized with grout. When full or partial depth casing is used, the frictional capacity must be adjusted. The casing in the upper sections of a micropile can also serve to increase lateral resistance and bending resistance for the micropile and can assist with more versatile connections to structural components at or above grade.
Sinorock strives to meet your specific hollow anchor bolt needs so you can compete in the anchoring industry. We offer a wide range of services that add value to your company. The company has modernised its plant with capability to produce its range of anchor bolts in any quantity to meet the demand in the Domestic and in the International Market.
Self Drilling hollow anchor use a hollow thread bar with a sacrificial drill bit which is drilled into the ground using grout as a flushing medium. This results in a grout body within the ground containing a high tensile steel bar. Corrosion is taken into account by typically over-specifying the bar with a sacrificial corrosion allowance and/or by the use of special coatings.
1.High strength self-drilling bars utilised for formation of a canopy ahead of mining very weak or highly stressed rock
2.Versatile product for secondary support of broken rock including rib and floor, where resin capsule anchoring is not practical
3.R32 continuous rope thread
4.Typically grouted with thixotropic “top-down” grout
5.Right hand(RH) thread for drilling with coal mining equipment
6.Stock lengths of 1.5m for RH thread
Combined with quality service and competitive pricing. We promise that we will try to ensure that our customers have a satisfying and productive experience every time they call our sales office or visit one of our websites.
If you have a custom need, can’t find a product, or are facing a difficult problem in the field, we’d love to know about it and do our best to help. Please feel free to contact us and we’ll get back to you at once.
Sinorock self drilling hollow anchor bars-These are fully threaded, hollow core, cold rolled anchors with continuous outside thread suitable for attaching bits and couplings, which also forms a superb mortar connection. They are supplied with couplings, anchor plates and nuts, and five bit designs are available.
At present, self drilling hollow anchor has good supporting effect in good geological conditions, while in soft and complex conditions, such as crushing, high ground stress in tunnels with large deformation, the challenge of self drilling hollow anchor support is quite difficult.
Nowadays, self drilling hollow anchor at home and abroad is moving to the effect of improving anchoring force, efficiency of support and expanding application range. It is believed that developing self drilling hollow anchor with plenty properties is an effect way to control high stress and big deformation, which is also the direction of self drilling hollow anchor’s development.
With the features of single operation of drilling, grouting and anchoring, anchoring
network can be created with a better chance of achieving both anchoring and
grouting. This procedure effectively eliminates the need for protective case pipes
and pre-grouting, simplifying the construction procedure and increasing