The 1987 standard IS 12023 outlines comprehensive guidelines for in-situ monitoring of structural displacements employing tape extensometers. It details the proper setup, measurement methodology, and upkeep required to observe movements in various civil structures such as slopes, tunnels, and excavations. This code is vital for professionals engaged in structural deformation analysis and geotechnical instrumentation.
Overview
The 1987 standard IS 12023 outlines comprehensive guidelines for in-situ monitoring of structural displacements employing tape extensometers. It details the proper setup, measurement methodology, and upkeep required to observe movements in various civil structures such as slopes, tunnels, and excavations. This code is vital for professionals engaged in structural deformation analysis and geotechnical instrumentation.
Audience
Contents
Structure
Frequently Asked
IS 12023 (1987) specifies that tape extensometers are applicable for displacement monitoring in various structural environments, including slope surfaces, tunnels, underground powerhouses, bridges, and buildings. The instrument measures changes in distance between two fixed points, enabling detection of relative movements or deformations. The standard guides the entire monitoring process, from installation to data collection and maintenance, ensuring dependable measurement outcomes.
Per IS 12023, tape extensometer installation requires secure fixing between the two points under observation, such as on slopes or tunnels. The tape must be tensioned so that the index marks just align without overlapping, as illustrated in the code’s Figure 4. Over-tensioning or slack causes inaccurate readings by misaligning the index marks. Maintaining proper tension ensures precise displacement measurement and reliable data collection.
Common error sources identified in IS 12023 include loose connections of reference studs, hooks, and anchor rods; misalignment between the tape and the measuring instrument caused by improper matching of reference points; slack in the tensioning spring leading to inaccurate tape tension; and environmental influences or inadequate calibration. To minimize errors, all components should be firmly fixed, aligned correctly, tensioned appropriately, and instruments calibrated regularly.
According to IS 12023 Clause 7.1, observations must be systematically recorded using the prescribed proforma, documenting initial and final readings with corresponding dates and observer details. Although the standard does not mandate a fixed observation frequency, typical practice involves daily or weekly measurements depending on the structure’s movement characteristics. Frequent readings during critical phases and adjustment based on observed displacement rates help ensure effective monitoring.
To maintain accuracy as per IS 12023, instruments should be calibrated before and after each measurement session using the portable calibration frame. The steel tape must be inspected for damage, cleaned regularly, and kept free from rust or dirt. Observations should be systematically recorded using the proforma to track displacement trends precisely. Additionally, verifying the measuring range and accuracy periodically enhances reliability and measurement precision.
Ask AI about any clause, requirement, or provision in IS 12023. Get instant, clause-cited responses powered by our indexed library.
Free tier includes 150 queries (50 AI + 100 Reference) · No credit card required