Excalibur speeds up with HS2 and Camfaud
Excalibur’s 16mm screwbolts have been successfully deployed on the high profile HS2 project*
Essex’s Camfaud Concrete Pumps Ltd was chosen to supply a "mission-critical" method of concrete placement on the HS2 project (that incorporated concrete pumping of tunnel inverts) and, in turn, the company chose Excalibur Screwbolts to fix the concrete pumping pipework. Excalibur Screwbolts’ speed of installation and removal with immediate high load fixing capacity are key advantages in temporary works applications providing customers with substantial whole life cost benefits.
In August 2021, Camfaud was engaged on the HS2 critical path project. The project was facing the prospect of programme delays unless a solution was found in relation to pouring the tunnel invert at the site in West London.
The Camfaud method was to install a pipeline and a specialist concrete pump. In order to satisfy health and safety requirements, specialist brackets were required to hold the pipeline in place within the 9 m diameter tunnel. Each bracket was secured with four Excalibur Screwbolts. The initial target distance was 600 m.
Phase One of the project incorporates the development of the high-speed railway line from London to the West Midlands and incorporates civil assets (such as tunnels, viaducts and cuttings), stations and railway systems.
Due to the nature of the project and distances involved, the situation required no ‘ordinary’ pipeline and such a high-pressure pipeline is only used in small percentage of jobs. The high pressure allows the dense concrete to be pumped a further distance – with significant forces being generated by the pumping process. For this reason, it was vitally important to anchor the pipeline effectively; this would also ensure that couplings stayed together, and the entire structure remained safe. The Camfaud method was to utilise one bracket every other pipe, with each bracket being secured by four Excalibur Screwbolts. With approximately 100 brackets in total, about 400 Excalibur M16 100mm HSB bolts were deployed.
Working tirelessly, the Camfaud team of highly trained operators installed eight brackets per shift, with two shifts per day, which resulted in a steady 15 m advance per day for approximately three weeks.
The contractors’ choice of concrete meant that there were restricting factors to the material pumping aspect of the project – due to fluidity factors. The specialist Camfaud pipelines would hit the highest pressure that any pipeline could take – but the reliability of the Excalibur Screwbolt system ensured that components remained in place and safe. This combination of the Camfaud pumping system and Excalibur Screwbolts facilitated substantial labour cost savings from shortened concrete placement times. Important worksite safety was enhanced, as was general construction quality.
*HS2 is the new high-speed railway that will form the backbone of Britain’s transport network. It will connect towns and cities in the South, Midlands and North and will be the low carbon option for long distance travel. As part of its ambition to be a highly sustainable high-speed railway, HS2 contractors have engaged suppliers that are able to innovate whilst minimising carbon footprint.
