Road safety barrier

Abstract

A road safety barrier ( 1 ) comprises a series of beam sections ( 2 a to 2 d ) together forming a length of barrier and supported above the ground by way of posts ( 3 a to 3 g ). The positions of successive posts along at least part of the length of the barrier shift relative to the centres of the beam sections (C). The shift may be progressive but uniform along a section thereof so that the flexibility of the barrier is substantially constant. Shifting the locations of the posts along the length of the barrier by an increasing or decreasing amount has the effect of increasing or decreasing the strength of the barrier so that different road conditions can be accommodated even though beam sections of constant length are used to construct the barriers.

1 . A method of constructing a road safety barrier which at least in part comprises a series of beam sections of substantially equal length supported above the ground by posts, the method comprising shifting the locations of the posts relative to the centres of the beam sections from one beam section to the next.  
   
   
       2 . A method according to  claim 1 , wherein the spacing between the posts is substantially equal such that said part has a substantially uniform flexibility characteristic.  
   
   
       3 . A method according to  claim 1 , wherein the spacing between the posts progressively varies from one beam section to the next such that the flexibility of the part of the barrier varies along its length.  
   
   
       4 . A method of testing a crash barrier system, the system comprising a series of beam sections together forming a length of barrier and supported above the ground by way of posts, wherein the positions of successive posts along at least part of the length of the barrier shift relative to the centres of the beam sections such that the stiffness of the barrier varies along the length, the method comprising conducting road crash tests at differing points along the length and determining whether the results of said crash tests satisfy predetermined criteria.