DYWI® Drill Hollow Bar System
The DYWI® Drill Hollow Bar System combines the geotechnical load-bearing system with the creation of a borehole. Thanks to the self-drilling hollow bar system with simultaneous grout flushing, the installation procedure can be decisively eased and shortened.
The DYWI® Drill Hollow Bar serves as a drill rod. It is fitted with a lost drill bit at the top that can be adapted to different soil conditions. After each single section of 1 to 6m, the subsequent bar is coupled to the previously installed segment.
At the final stage of drilling, cement mortar is injected into the hollow core of the bar using an injection adapter that is mounted at the drilling unit. The grout flushing simultaneously serves as slurry to stabilize the borehole and ensures the efficient retroflush of the borehole cuttings. Once the required installation length has been reached, the grouting unit is switched to grouting mortar because it reaches higher compression strengths and thus ensures better load-bearing capacities.
The hollow bar now serves as a steel tendon and can be used both as a soil nail or rock bolt and as a micropile. The comprehensive DYWI® Drill Hollow Bar System product range offers tendons with ultimate loads from 210kN to 1,900kN including all system components such as drill bits for all soil conditions, couplers, spacers and anchor heads.
1. Drilling Adapter with Grout Bottle for Grouting
2. DYWI® Drill Hollow Bar
3. Cement Mortar
5. Retroflushing for Stabilization and Load Transfer
6. Drill Bit
- The tendon simultaneously serves as a drill rod
- Extremely fast installation because borehole drilling is made redundant by simultaneous drilling and grouting
- Compact equipment – space saving installation
- Drill bits are available for all varieties of soil and rock
- Can be used as a nail or a pile – many head varieties are available