HC Deb 14 December 1978 vol 960 c346W
Mr. Watkinson

asked the Secretary of State for Transport what force motorway bridges are designed to resist in circumstances of lorry or car crashes.

Mr. William Rodgers

Since 1973, it has been a requirement that safety fences shall be provided to protect bridge supports subject to possible vehicular collision and, in addition, that the supports shall be capable of resisting all of the following loads applied concurrently:

  1. (a) Due to impact from safety fence a lateral load of 225 kilo Newtons and a longitudinal load of 75 kilo Newtons applied at any one bracket attachment point or, for free standing safety fences, any one point 750mm above carriageway level.
  2. (b) Due to residual impact above guardrail a lateral load of 150 kilo Newtons and a longitudinal load of 150 kilo Newtons applied at any one point between lm and 3m above carriageway level wherever the effect is most adverse.

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