Main function of self drilling rock bolt in concrete structure

The main function of self drilling rock bolt in concrete structure is bear tensile force to cover poor performance of tensile strength and shortage of ductility.

Structurally, self drilling rock bolt is divided into anchorage section in rock body, free section between rock body and free section in concrete. Intense water pressure between concrete and rock body may be transferred directly into acting force between self drilling rock bolt and concrete.

With the load increase on self drilling rock anchor, the maximum displacement of bond stress between self drilling rock bolt and slurry body moves down to the fixed segment, slides in gradual way and distributes in the way of changing bond stress. Initially, adhesive force has effect near anchoring segment. When adhesive force is overcome, slide will be produced and most bond stresses will be transmitted to the far side of anchoring segment, then friction force at near side has little effect.
Basing on the demands of slope engineering, geological condition, slope feature, scale, shape, deformation degree and construction condition, pre-stressed rock bolt or coalition of non-prestressed anchor bolt, support pile, retaining wall and sprayed concrete can be adopted to sustain slope stable.

Under condition of the same safety factor for slope stability, pre-streesed rock bolt is safer to provide supporting and resisting power, which can be used for slope reinforcement, slope earth- retaining, anchoring retaining wall, landslide prevention, etc.