Indian Standard IS 16172: 2023 Overview

This standard covers the requirements for reinforcement couplers.

It does not cover the performance of spliced joints in the field.

Length of swaged coupling sleeves, grout/steel filled sleeves, etc., longer than 100 mm are now addressed.

The report format for static tensile tests was clarified.

The frequency of sampling and criteria for acceptance are based on industry requests and international standards.

Packing requirements for couplers have been added.

Practical considerations led to modifications in the validity period of type tests.

Guidance for mechanical splicing quality control checks during construction is provided.

The minimum yield stress or 0.2 percent proof stress of the reinforcing bar. This value determines the bar's strength and is specified in IS 1786.

A mechanical device used to connect two reinforcement bars, ensuring continuity and structural integrity.

A type of coupler designed to connect reinforcement bars of two different sizes.

A test that assesses the ability of a threaded coupler to withstand static tensile forces. It ensures the coupler can handle the load without failing.

A test that evaluates the ability of the coupler to resist elongation during the application of force. This ensures the coupler maintains its form and does not stretch excessively.

The thread quality of the coupler is inspected using 'GO' and 'NO GO' gauges to ensure its proper fit and functionality.

The amount of thread length that can be removed from the coupler while still maintaining its required performance in the static tensile test. This ensures safety and reliability even with slight imperfections.

The location where the coupler should fail in a tensile test. The failure must occur in the reinforcing bar outside the coupler to ensure the spliced joint is stronger than the original bar.

The length of the test piece after unloading the mechanical splice minus the original gauge length before loading. This determines the free length available for elongation.

The minimum sufficient free length for slip testing. This length helps ensure sufficient elongation for accurate slip measurement.

The gauge length measured after the mechanical splice is unloaded in a tensile test.

The gauge length measured AFTER the test piece is secured in the tensile testing machine but BEFORE any load is applied.

A type of extensometer that measures the average strain over a defined length.

A type of extensometer that measures the average strain over a defined length, using three points for a more precise reading.

The device used for measuring the slip, which is the movement between the two parts of a mechanical splice.

The process of setting the extensometer to zero before starting the tensile test.

Reinforcing bars connected using grouted couplers, where the grout is contained within the designated areas.

This test involves applying cyclic stress to a mechanical splice, simulating the stress variation during normal usage. The splice must withstand 100 cycles of 5% to 90% of the reinforcement bar's yield strength without losing its static tensile strength compared to a non-spliced specimen.

This test is designed to determine the ability of the mechanical splice to withstand repeated stress cycles. There are two types: low cycle fatigue test and high cycle fatigue test. Couplers of class H need to pass both tests.

Involves applying stress cycles, mimicking the loads experienced in construction. Each cycle ranges from 5% to 90% of the bar's yield strength.

This test aims to check if the splice can endure a high number of stress cycles without failing. It is mandatory for couplers classified as class H.

To evaluate the actual strength of the reinforcement bar used in the splice. This is crucial because the performance of mechanical splices is directly linked to the properties of the steel.

The rib geometry of the steel bar can affect the splice's performance. This information is recorded with the test results. This requirement doesn't apply to threaded couplers.

To ensure that the assembled splice is ready for its intended use, the manufacturer's instructions must be closely followed. This is crucial for the test results to accurately represent real-world performance.

This refers to the yield strength or 0.2% proof stress of the reinforcement bar as specified in the Indian Standard IS 1786.

Tensile strength is the maximum force a material can withstand before breaking under tension. It's measured in units of force per unit area, often in megapascals (MPa).

The percentage elongation at maximum force is a measure of how much a material stretches before it breaks. It's expressed as a percentage of the original length.

The slip test measures how much the connection between spliced reinforcement bars moves under load. It's measured in millimeters.

The gauge length for measuring slip is the distance between the points where the strain gauges are attached. This length is carefully chosen to ensure accurate measurement.

The load-extension curve is a graph that shows how the force on a material changes as it is stretched. It's a way to visualize the material's behavior under tension.

The location of failure refers to where the spliced specimen breaks during a tensile test. Identifying this location is important for understanding the strength of the connection.

The standard specifies the minimum information that each test report should include for both spliced and un-spliced specimens.

The standard specifies the minimum information that includes the tensile strength, percentage elongation at maximum force, load-extension curve, and location of failure.