scope:

This document covers the procedure for selecting the type of temporary restraint to mitigate risks associated with failure of earthworks.

The scope does not include the permanent installation of physical barriers and restraints or emergency works other than the use of temporary restraints. This is documented in NR/L3/CIV/071 and NR/L2/CIV/086/Mod04.

Purpose

Temporary restraints are implemented as part of the mitigation of risk associated with earthworks failure.

This document supports the control, 'earthworks mitigation', mitigating the following risks:

a) loss of track support or track geometry;

b) slope failure leading to loss of kinematic envelope or track geometry.