Timber Products from Outdoor StructuresInnovative timber technology by Outdoor Structures

Swale Drain Bridges

A simple but effective low priced swale drain bridge is now available from Outdoor Structures. The bridge is based on the member sizes and widths from our very successful Boardwalk Design Guide, with overall length in modules of 120mm. Stainless fasteners are an option.

Swale Drain Bridges from Outdoor Structures

SD2514 (25 boards)1.4
SD2517  1.7
SD2523  2.3
SD2526  2.6
SD3114 (30 boards)1.4
SD3117  1.7
SD3123  2.3
SD3126  2.6
SD4314 (40 boards)1.4
SD4317  1.7
SD4323  2.3
SD4326  2.6
SD4914 (45 boards)1.4
SD4917  1.7
SD4923  2.3
SD4926  2.6
SD6114 (55 boards)1.4
SD6117  1.7
SD6123  2.3
SD6126  2.6
Span is centre/centre of hold downs, bridge is 0.5m longer

For further information on this range of certified bridge superstructures contact Ted at Outdoor Structures: email. We can also assist with abutment design.

This information is also available as a one page full-colour brochure:
Swale Drain Bridges

Close up of Swale Drain Bridge hold down Swale Drain Bridge blends in well in a residential developement

Close-up of Swale Drain Bridge hold down

Abutment Design Notes For Swale Drain Bridges

The abutment should be designed with the following in mind:

    Avoid this outcome for the abutment design of Swale Drain Bridges

    Figure 1 Avoid this outcome

  1. The bridge should not be installed beyond a maximum 5% slope.
  2. The bridge sill should not sit directly on the abutment but be spaced up to 50mm above on drypack concrete or neoprene blocks.
  3. The abutment should have a concrete backwall and a side wall to stop soil encroaching on the timbers
  4. The abutment should slope about 25mm across its width to shed moisture
  5. Design reinforcing so there is no clash with the hold down bolt positions
  6. The bridge is only intended to withstand nominal flood loads

If handrails are required use the demountable series bridge. Bikeway compliant rails are needed on virtually all bikeway bridges.

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