scope:

This guidance note is applicable to ground investigations for the geotechnical design of all types of foundation engineering and slope stabilisation works, for example:

a) Earthworks;

b) retaining walls;

c) bridge foundations;

d) piers, abutments and wing walls;

e) tunnels and tunnel components including construction shafts; and

f) foundations to buildings.

The document applies to the assessment of all earthwork assets and ground bearing structures that have the potential to affect the operational safety of Network Rail controlled infrastructure, outside party infrastructure and landowners.

Ground investigations (including geophysics) apply to intrusive and non-intrusive works and determine ground conditions and the presence, composition, properties or dimensions of:

a) structures

b) units of natural or made ground

c) mining

d) groundwater

e) drainage.

This guidance note does not apply to:

• topographic surveying (see NR/L2/TRK/3100)

• trackbed investigations (see NR/L2/TRK/4239)

Purpose

The purpose of this guidance note is to provide guidance, information and best practice on the design and implementation of ground investigations.

This document provides guidance on railway specific aspects of ground investigation, including ecological surveys, contaminated land investigations, avoiding buried services, operational railway restrictions and mining investigations.