Ground anchors are defined as a pre-stressed element which actively contribute to the stability of the structure throughout its design life. Unlike passive elements the performance of the anchor is critical to the stability of the structure.
Force is applied to the surface of the wall or slab by pre-stressing the anchor using a stressing jack to elongate the tendon, once the necessary load has been established, the anchor is “locked off” at the head. From this moment onwards the anchor will be applying a compressive load to the structure to arrest movement.
To prevent load from being transferred into unsuitable material and to ensure sufficient elongation of the tendon is possible, the tendon is de-bonded from the ground between the structure and the load-bearing strata. Upon reaching the desired depth, the tendon is directly bonded to the ground. This forms the two fundamental elements of the ground anchor, the free length and the bond length.
Critical characteristics of ground anchors are:
- Length (Free & Bond Lengths)
- Tensile Capacity
- Relaxation Rate
- Installation Angle
- Corrosion Protection
As the quality of available space for development reduces, the requirements for ground anchors increase, and the challenges facing ground anchoring change. In addition to our conventional systems, we have developed specialist anchoring products for:
- Anchors in poor soil conditions
- Removable anchors for use in urban environments
- Cuttable anchors that can be left in the ground following their use without causing an obstruction to future development
All ground anchors must be tested and their capabilities proven before they can be commissioned. Therefore, we have a dedicated team of specialist technicians that supply stressing and testing services as well as a large range of bespoke equipment for hire.