ISO 18674-3:2017/Amd 1:2020

Overview

ISO 18674-3:2017/Amd 1:2020 is an important amendment to the international standard focused on geotechnical investigation and testing. It specifically addresses geotechnical monitoring using field instrumentation, with an emphasis on measurement of displacements across a line through inclinometers. As part of the ISO 18674 series, this standard enhances methods for accurately detecting and quantifying lateral ground movements, which are critical for assessing soil and structural stability in civil engineering projects.

This amendment refines measurement protocols to improve reliability and repeatability when using inclinometers for displacement monitoring. It is developed by the ISO Technical Committee ISO/TC 182 on Geotechnics in cooperation with the European Committee for Standardization (CEN), ensuring broad applicability and harmonization with regional standards.

Key Topics

• Geotechnical Monitoring
  The standard advances in-situ instrumentation techniques that provide real-time monitoring of ground displacement, crucial for early-warning systems and safety management.

• Inclinometer Use
  Guidelines are detailed for the deployment and interpretation of inclinometers aimed at measuring displacements perpendicular to a monitored line, offering precise detection of subsurface lateral shifts.

• Measurement Accuracy and Repeatability
  Amendment 1 introduces improved definitions for displacement measurement over 24-hour periods under repeatability conditions, clarifying the non-cumulative limit on measurement difference to enhance data consistency.

• Field Instrumentation Protocols
  Specifies field procedures to ensure reliable installation, data acquisition, and quality control for geotechnical monitoring projects involving inclinometers.

Applications

ISO 18674-3:2017/Amd 1:2020 serves a wide range of practical applications within geotechnical and civil engineering fields:

• Slope Stability Monitoring
  Continuous displacement measurement helps detect slope movements, landslide risks, and ground instability, enabling timely mitigation actions.

• Foundation and Retaining Structures
  Monitoring lateral displacement around foundations and retaining walls aids in assessing structural integrity and soil-structure interaction.

• Tunnel and Excavation Safety
  Displacement data gathered using inclinometers inform the safety and design adjustments required in underground and excavation works.

• Infrastructure Health Monitoring
  Bridges, embankments, and embankment dams benefit from precise inclinometer measurements to identify potential failures induced by soil movement.

• Environmental and Natural Hazard Assessment
  Enables detailed tracking of ground movements caused by natural events such as earthquakes or subsidence.

Related Standards

ISO 18674-3:2017/Amd 1:2020 is part of the broader ISO 18674 series governing geotechnical instrumentation, which includes:

• ISO 18674-1 - General requirements for geotechnical monitoring instruments
• ISO 18674-2 - Measurement of groundwater pressure using field instrumentation
• ISO 18674-4 - Measurement of soil displacement using extensometers

It also closely aligns with European standard EN 18740 for geotechnical monitoring, ensuring consistency in international and regional geotechnical best practices.

Implementing ISO 18674-3:2017/Amd 1:2020 ensures standardized, accurate, and reliable measurement of lateral displacements using inclinometers, supporting safer design and monitoring of geotechnical structures and installations worldwide. Adherence to this amendment facilitates enhanced data quality and improved risk management in geotechnical engineering projects.