24 May 2019
The final phase of the work programme – building the buttress wall near Sundale – to further secure the section of rock in the upper Jamestown area is nearing completion, with the masonry crew of the Roads Section, assisted by the Rock Guards, now in the final stages of construction on the wall.
Works carried out so far include:
- Excavation of over four cubic metres of loose rubble for foundation, digging down nearly one and a half metres before reaching solid rock using only small hand tools and electrical breakers
- Drilling holes and installing metal reinforcing starter bars and rebar cage to anchor the foundation to the solid rock base
- Pouring the concrete foundation and allowing to cure over seven days
- Construction of the wall itself using cavity blocks, with the spaces between the blocks and around the rebar being filled every two layers
- Construction of scaffolding around the buttress wall to allow for construction of the higher section
Due to the precarious location of the works, eight plus metres below the cliff top, the works team have had to install contraptions to allow for the transporting of material. These include constructing a zip line to assist in moving material from the cliff top to the works site, and constructing a metal chute to allow fresh concrete to be mixed at the top and transported down to the base foundation.
Roads Manager, Deon Robbertse, said:
“The biggest challenge from the outset was to ensure a safe working space for works to be carried out. This included installing mechanisms to allow material to be transported safely from the top to the bottom.
“A big thanks must go out to the guys, who, under very difficult conditions, are doing their best in constructing this buttress wall.”
The remaining works include completion of the buttress wall construction using cavity blocks, estimated to be finished by mid-June, and tying in the buttress wall to the cliff above.
Once completed, the works team will need to clean up the site by removing the zip line, scaffolding, and metal chute, and resetting the rock fall catchment fencing.
On successful completion of these works, the work programme will be concluded.
Notes to Editors
The Rock Guards, who carry out regular rock stability inspections, expressed concerns about a section of rock in the Upper Jamestown area on 21 June 2018. On 23 June, Geo-Tech Surveyor, Chad Douglas, visited the Island to carry out an inspection of the area. His assessments indicated that there is no imminent risk of a rock fall and an appropriate work programme was put in place to further secure the area.
#StHelena #InfrastructureAndTransport #RoadsSection #RockGuards #ButtressWallConstruction #AltogetherSafer
24 May 2019