Paraslim, RMD Kwikform's modular cantilever formwork system, has been successfully used on two major roadwork schemes in the UK. It was adopted for the construction of bridge deck edges on the A30 Kennards House Junction in Launceston, Cornwall, being built by Tilbury Douglas, and the much-publicised Costain Civil Engineering A34 Newbury By-pass in Berkshire. Both were hire contracts.

Cost – Paraslim is half the cost of under-slung or over-slung systems because it uses substantially fewer components – was among the deciding factors in the selection of Paraslim for both schemes. So too was safety, as Paraslim is both safe to erect and safe to use. Rapid erection was another major consideration. Projects have shown that up to 50 metres can be erected and levelled in a single shift by two formwork erectors and one engineer.

Another feature of both installations was that Paraslim did away with the need for access beneath the soffit. The system allowed all of the erection levelling, tilt adjustment and stripping operations to be carried out safely from deck level. Safety handrails were attached to the outer edge of the Paraslim assembly and deck edge formwork was supported off the frame.

The ability to pre-assemble sections or modules of Paraslim on the ground and then crane them into position was another major consideration. This was particularly the case on the Kennards House Junction site where there was insufficient room for a conventional under-slung system.

The Paraslim system is based on a triangular frame supported by a single diagonal tie. This tie is attached to a Paraslim bracket, unique to RMD KWIKFORM, which is fixed to the top of the bridge beam. The triangular frame itself is formed by using RMD KWIKFORM Super Slim Soldiers as the primary beams, which support conventional RMD KWIKFORM Alform beams, Alsec beams or timber bearers that in turn support a plywood soffit.

A Super Slim Soldier turnbuckle is used for the diagonal member of the frame which, when rotated, adjusts the inclination of the deck soffit. The final major component of the triangular frame is a purpose-designed, adjustable Paraslim Tube, which is strutted-off the face of the bridge beam. Shaped soffits, such as that featured on the Kennards House Junction bridge, are easily accommodated by attaching special formers to the top of the Paraslim plywood decking.

The Paraslim system was introduced in 1997. It was designed by RMD KWIKFORM in response to the worldwide call for more efficient and less costly methods of forming cantilevered deck edges for bridges and elevated highways. It can also be used to form soffits to sheet pile capping beams.

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