This is the working platform which the piling rig will need to track over and install the piles from. The platform is made up of appropriate material to carry a piling rig that will weigh over 30 tonnes.

Please see our Working Platform page for a copy of our Working Platform Certificate and the loadings each piling rig generates. There are also Working Platform requirements on the FPS Website.


Materials and Installation

Generally some form of reduced dig or grading of the ground surface along with the removal of underground obstructions and diversion of services is carried out prior to the platform being installed. Subject to the specific requirements of the working platform design, the platform would typically comprise a geotextile membrane laid on the prepared subgrade, then covered with granular material (particle size normally 75mm down to dust) laid to the thickness specified in the design.

Soft spots in the subgrade must be excavated and backfilled in compacted layers using granular fill. In certain situations platform thickness may be reduced through use of geo grid reinforcement.

The platform should overlay the footprint of the building plus a minimum of 2 metres all round. Access pathways are maintained, this will provide a safe environment for the piling rig and crew to work in.

A piling rig is taller, wider and longer than most 360 degree excavators and has a variable center of gravity. Rigs are therefore not as manoeuverable as excavators.

A large area is required for unloading, setting up and moving a piling rig around a site. Roads should be kept clear of parked vehicles in the vicinity of the site entrance to allow easy access and safe unloading. Any notices or approvals are to be arranged by the Principal Contractor in advance of the rig delivery.

In transit mode, a rig is up to 3.0m wide and 17m long. Once set up ready to work, a rig is up to 4.5m wide, 8.5m long and 30m in height. In addition to the rig, the auxillery equipment and materials are normally delivered on a fleet of articulated and rigid hiab lorries.

A static agitator is used for storage of ready-mix concrete, up to 20 loads being delivered per day. The concrete is pumped through a reinforced rubber ground hose to the rig (maximum practical pumping distance approx. 100m). Dumpers, excavators and wagons must be prevented from crossing the ground hose as this can lead to catastrophic hose failure.

The space required for the agitator and pump set-up is approximately 4m x 15m, and must have suitable access for ready-mix concrete deliveries. A mains pressure water supply is also required for priming the pump up at the start of the shift and washing out the pump and ground hose at the end of the shift. In addition, an area is required for fabrication and storage of reinforcement cages along with access for a crane.

A site visit may be required to assess suitability of plant and equipment. Particular attention should be paid to neighbouring buildings with roof overhangs. Generally 1m side clearance is required over full height of rig.

Party-wall approvals are normally required and site specific safety procedures must be agreed for works adjacent to railways or tube lines.

The two common types of pile test are sonic integrity testing and maintained load testing.

Sonic Integrity Testing
The number of piles to be tested is determined by the contract along with the number of visits. The test is normally carried out once the piles have been trimmed to cut-off level. It should be borne in mind that a minimum of 3 working days notice is required for a test visit.

Pile trimming should not be carried out until the pile has been cast 7 days. Various methods are available along with techniques that facilitate trimming e.g. reinforcement de-bonding. The methods and techniques adopted would vary according to pile size and depth of cut off.



Maintained Load Test
For a maintained load test a steel collar is cast on the pile, and anchor piles are installed around the test pile in a grid arrangement. After installation, the test area must be cordoned off and kept clear of site traffic to prevent damage to the test and anchor piles. The test cannot be carried out until 7 days after installation or when the concrete has reached a minimum strength as specified in the design.

Preparation of a construction site for piling requires more consideration and planning than may be first thought. On this page we provide a brief outline of what our works involve and what we require from the Principal Contractor to achieve safe working conditions for our operatives, a cleaner site and improved production.

A properly prepared site will ensure a tidy safe working area as well as reducing time on your programme at an early stage. Please contact us if your require more information on Site Preparation for Piling.

Please select from the sub-menu for more information.