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5 | Cross section, scale 1:25. The loadbearing construction consisting of four 1287-1650 x 200 mm glulam beams, 130-150 x 90 mm transverse deck beams, 39 mm KERTO veneer laminated wood panels. Balustrading: 50-240 x 70 mm posts, to which the

50 mm dia. steel handrail and steel mesh infill are fitted.

Weather protection: 120 x 30 mm planks supported on 180 x 50 mm members cut to a sawtooth shape and fixed at an angle on the bridge construction.

by means of steel channels. Suspending joints in timber beams is advisable so that the timber is always in compression and is not subjected to shear failure. The depths of the main beams vary: 1287 mm in the end spans, 1485 mm in the centre span and 1650 mm over the supporting piers. Attached to these main beams are the transverse deck beams at 1000 mm centres: 80 mm wide and varying in depth from 150 mm in the middle to 130 mm at the edges. This produces the gentle camber required for drainage purposes.

KERTO veneer laminated wood panels, 39 mm thick, are screwed onto the deck beams. These panels not only carry'the imposed loads, they also brace the bridge against wind and horizontal forces. The surface of these panels is sealed with a liquid polyurethane material on a bonding coat and then finished with AB11N asphalt as the deck surfacing and weatherproofing.The deck beams cantilever 650 mm beyond the edge beams. These cantilevers are strengthened by 150 x 90 mm sections screwed on underneath. Bolted onto the now 280-mm-deep beam ends are the posts for the balustrading: 75 mm wide x 240 mm deep at the fixings, tapering to 50 mm at the top. Also attached to both sides of the strengthened ends of the cantilevers is the framing for the protective cladding comprising horizontal planks. This framing is fixed at an angle of 70° to the outer main beams. The 120 x 30 mm planks at 220 mm centres are placed at 450 to the horizontal and hence protect the loadbearing main beams against the weather.

The balustrading consists of a handrail made from hot-dip galvanized tubing, 50 mm dia., and a welded, hot-dip galvanized mesh infill panel, 3.5 mm-dia. wires in a 40 x 40 mm mesh, all screwed directly to the posts. All timber members subjected to the weather, such as posts and protective cladding, are made from weather-resistant larch and easily renewable in case of rotting. Chemical preservatives were therefore not necessary.

Construction | The timber construction company was responsible for organizing transport, intermediate storage and the entire assembly procedure. They set up temporary erection towers under the joints in the main beams; a number of forked mountings, used to support the beam ends during erection, were temporarily fixed to the concrete piers. Two mobile cranes were used, one on each bank standing on tipped rubble embankments. It took only four days to erect the beams and lay the deck surfacing, helped by the fact that the deck beams and posts for the balustrading had been prefabricated into U-shaped elements prior to transportation.

The side cladding and its framing was attached by the construction team using a movable platform which they had designed themselves. This was suspended below the bridge deck on both sides; soffit scaffolding was not required.

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