29/06/09
As part of a feasibility study into the construction of a new viewing platform on top of a 100m high cliff on the Pembrokeshire Coast a geological survey of the cliff below was required.
Abcas were employed to provide a safe means of access & supervision for the duration of the site works.
The benefits of using rope access techniques for this work included:
- Speed of set up and dismantling of the access system
- Minimal environmental impact to a sensitive area of National Park
- Flexible system allowing the engineer unlimited access to the survey area
- All equipment removed from site at the end of a shift reducing disruption and risk to the public.
Posted in Geotechnical
07/12/08
Following several rockfalls onto a narrow main road in West Wales Abcas were awarded the contract to initially scale the rock cutting and then install rockfall protection netting. Protective fencing and a traffic management system were required to ensure the safety of road users during our works as the road had to be kept open.
Works were completed within budget and on schedule.
Posted in Geotechnical
01/10/08
Unstable rock on an old quarry face was threatening the workforce below. Abcas were employed to provide a team of experienced workers to inspect and remove dangerously loose rock from the face.
Hand tools were used to prise off loose rocks leaving a safe face for workers to continue operating below.
The team were able to access the slope using rope access techniques. The area below the rock face was cordoned off whilst the work was carried out.
Some rock fall netting & associated anchors were installed in other isolated areas of the quarry where scaling was not suitable.
Posted in Geotechnical
01/07/08
Stabilisation works were required to a 30m high sea cliff following the construction of new properties above.
Access to the crest was severely restricted and the only option was to use rope access techniques. The undercut rock face required a combination of stabilisation methods to ensure it’s long term integrity including:
- Rock bolting of isolated blocks
- Installation of restraint cabling to isolated blocks
- Installation of Geobrugg Tecco mesh support to face
- Installation of Geobrugg Spider mesh support to overhangs
- Installation of rock dowels
- Construction of sprayed concrete scour protection wall at base of cliff
- Sprayed concrete erosion protection to weak areas of face
Rock bolts ranged from 3m to 9m in length and installed into holes of 45-100mm diameter using both fibreglass and high tensile steel anchors. All anchors were cement grouted. Drilling techniques included the use of hand held rock drills, a drifter mounted on a mast and a DTH system for the larger diameter anchors.
All works were completed to the engineer’s satisfaction, contract duration was 4 months.
Posted in Geotechnical
07/08/07
Posted in Geotechnical
