If you’re adapting an existing channel, you might like test out our system. We can supply sample lengths of Unistrut and sample blocs for your contractor to assess.
Need more blocs to change and develop your course? We can supply individual blocs or complete sets usually within three months of your order.
Our blocks are built to last. RapidBlocs have a two year UK warranty against defects in materials and workmanship. Contact us for details of the warranty in your territory.
Frequently Asked Questions
We can provide general design advice and whitewater engineering design through either EPD or S2O. epduk.com s2odesign.com
RapidBlocs is our three‐dimensional obstacle system and is generally supplied in two shipments.
- The Unistrut track is provided to the construction contractor/builder during concrete channel construction.
- A shipment/delivery of RapidBlocs components is made once the channel is nearing completion for installation and whitewater commissioning.
Unistrut track for the concrete can generally be supplied with 4 weeks of order, depending upon final quantities required.
RapidBlocs can be supplied within 3 months from order. They are moulded and assembled in the UK by Palm Equipment International / Dagger Europe for RapidBlocs Ltd from high quality polyethylene.
We can assist with engineering design through consultancy work by EPD or S2O, our design consultancy companies.
We can provide commissioning and placement of RapidBlocs through EPD or RapidBlocs, charged accordingly.
We can and do provide RapidBlocs spares, servicing etc across the globe, as required by our clients with RapidBlocs installations. This can include supply of extra units, upgrades to newer product lines and replacement and recycling of damaged units as required.
There are design criteria that must be met for the placement and use of the system and these are explained in our Operation and Maintenance manual.
Providing that these criteria are met we will provide a standard UK warranty. This could be extended to other regions with some understanding on final terms.
RapidBloc UK Warranty – 2 years against defects in materials and workmanship. This does not cover normal wear and tear, nor damage resulting from abuse, alteration or unauthorised repair.
(Note that some channels have vertical concrete walls, others have sloped sides (vertical is much cheaper to construct). RapidBlocs has a standard product to infill the gap in the sides of sloped walls).
We refer to the oblique elements as Groynes and these are at an angle of 3 vertical to 2 horizontal (3v:2hz) and interlock and integrate to the Blocs in multiples of 3, generally. They are attached to the walls of the channel by with 2 plates attached (in the factory) and then using bolts (supplied) to attach to the channel wall in the desired location. The groyne and connected RapidBlocs wall can be easily moved by over drilling the depth of the holes in the channel walls slightly during initial installation, the nuts can be removed, the bolts cut and tapped in the holes (leaving no extrusion) and the arrangement relocated at new location. There is a tongue on the side of the Groyne to fit in an accommodating slot in the adjacent RapidBlocs.
For the Groyne to fit correctly the wall must be exactly 3v:2hz otherwise there will be a gap between the obstacles and the wall plus there will be a weakness in connection from the groyne to the wall.
We can supply security locking nuts that require a bespoke tool to remove. We would generally recommend one locking nut per lid mechanism.
We recommend the use of Unistrut P3270 PG concrete inserts for the rail system. You can check out the manufacturer’s specification here. Other variations are available but the track must be compatible with Unistrut nuts as they are used throughout the RapidBlocs anchor system.
The Unistrut is made of pre‐galvanised (PG) steel, which protects it from corrosion. The benefits of stainless steel are outweighed by the additional cost.
Ask your local Unistrut supplier for a sample. Alternatively we can supply the rail (Unistrut 3270 PG) for a typical price of approximately £46 / 6m length delivered within Europe. Contact us to find your local Unistrut dealer or get a quote on a sample from us; we’ll need a delivery location and the number of sections required.
For maximum flexibility and strength of the placement of your blocs:
- 250mm from the edge of the channel / wall intersection to the centreline of the first Unistrut rail.
- 500mm centreline to centreline of the Unistrut channel across the channel.
A competent contractor will be able to place the track to within 5mm of the placement rules. The rail must be placed accurately otherwise you’ll lose flexibility in the final placement of the blocs.
We recommend that the rails are cut to 3m lengths (cut in half) for placement around corners to increase placement options of the blocs. We can assist with Unistrut rail; it is a common drawing for us to produce. The concrete must be finished within normal concrete tolerances for a structural slab.
3 vertical :2 horizontal. This is often difficult for a contractor to form in concrete, particularly on tight curves. Close supervision is vital – this is a common problem with poor construction contractors. We can provide assistance if required, and early delivery samples to ensure a good fit.
We have seen contractors utilising a number of techniques to place the rail. It is a common, fast and cheap arrangement for experienced contractors to place the rail. The most successful results are from ‘tack welding’ the rails to the concrete reinforcement prior to concreting the main floor slabs.
The design of whitewater channels is a complicated engineering process. EPD and S2O can help you design your course and the bloc placements needed to make great whitewater features. epduk.com s2odesign.com We can quickly produce a computer model and 1:10 Froude scale physical model of your course to make sure that your course is superb right from the moment the water is turned on. Alternatively we can survey your existing course flow, head and channel geometry then help you commission your RapidBlocs course with any necessary channel refurbishment. There are limitations to what is possible when refurbishing an existing channel. In general you will get better and faster results, with a detailed design and construction of a new course.