ISO/CD TS 17539

Railway infrastructure - Track foundation- Observation and evaluation method of railway subgrade settlement and deformation

Scope

This document specifies the general requirements relating to the observation and evaluation
method of railway subgrade (substructure and foundation ground) settlement and deformation
for new-built railway and existing railway.
(1) In Chapter “General Requirements”; the observation duration and interval of
settlement/deformation, the instrument calibration, etc. are defined.
The measurement conditions, the deformation monitoring network establishment, repeated
survey, observation level, observation accuracy, observation path and other measurement-
related technological requirements, as well as requirements on observation equipment,
observation data processing, feedback of and countermeasures for settlement/deformation
abnormalities and data abnormalities, are stipulated.
(2) In Chapter “Observation schemes for subgrade”, the key points of the observation of the
settlement/deformation of the earthworks are clarified, and the observation period, the
observation cross-section interval, the observation point layout, the observation frequency, the
starting time of the settlement observation as well as the cases where the observation frequency
is increased or decreased are defined.
(3) In Chapter “Observation prediction and evaluation”, the requirements on definition of
evaluation section, method of evaluation, time and conditions for evaluation are specified; the
influence factors that shall be considered in the evaluation are defined; the evaluation criteria,
prediction and analysis of the settlement of the observation points, as well as settlement
evaluation, are specified