Out of print publication, available as a photocopy only

Description: A survey and assessment of trench support methods in use in the UK was carried out in 1978 and reported in the first (1979) edition of this Technical Note. For this edition the text has been amended to take account of systems which have become available since 1978 and to delete references to systems no longer available in the UK. The performance data has not be reassessed. The criterion for inclusion is still that the system can be readily and rapidly installed before any person enters the trench. Some of the methods, particularly shields, are used to provide protection for people in the trench against ground collapse rather than support against collapse itself. When operators are experienced in the use of proprietary systems these are quicker to install than standard sheeting, waling and strutting methods. The quickest and cheapest method of trenching is one which maintains a near vertical sided open cut trench, but this is associated with the greatest risk.