Uji Kuat Tarik Baja Tulangan. (SNI 8389:2017)

Introduction

This tutorial provides a comprehensive guide on conducting tensile strength tests for reinforcing steel bars, in accordance with the Indonesian National Standard (SNI 8389:2017). Understanding and applying this testing method is crucial for ensuring the structural integrity and safety of construction projects.

Step 1: Prepare the Test Specimen

• Select the Sample: Choose a representative sample of reinforcing steel. Ensure it meets the specifications outlined in SNI 8389:2017.
• Cut the Specimen: The length of the steel sample should be appropriate for testing, typically around 1 meter, to allow for accurate measurement of tensile strength.
• Mark the Gauge Length: Use a marker to clearly indicate the gauge length, usually 200 mm, where the measurement of elongation will be taken.

Step 2: Set Up the Testing Equipment

• Use a Universal Testing Machine: Ensure the machine is calibrated and capable of measuring the tensile strength accurately.
• Install the Grips: Securely attach the specimen to the grips of the testing machine. Make sure the grips hold the sample firmly to avoid slippage during the test.
• Zero the Machine: Before starting the test, reset the machine to zero to ensure accurate readings.

Step 3: Conduct the Tensile Test

• Initiate the Test: Start the machine to apply tensile force to the specimen gradually.
• Monitor the Load and Elongation: Observe the readings on the machine's display. Record the load at various elongation points, particularly at the yield point and ultimate tensile strength.
• Document Results: Keep a detailed log of the load and corresponding elongation measurements throughout the test.

Step 4: Analyze the Test Data

• Calculate Tensile Strength: Use the formula: [ \text{Tensile Strength} = \frac{\text{Maximum Load}}{\text{Original Cross-Sectional Area}} ]
• Determine Yield Point: Identify the yield point from the recorded data. This is the load at which the material begins to deform plastically.
• Evaluate the Elongation: Measure the elongation at fracture to assess ductility.

Step 5: Report Results

• Prepare a Test Report: Summarize the test findings, including:
  • Sample identification
  • Test conditions and equipment used
  • Measured tensile strength and yield point
  • Any observed anomalies during testing
• Compare with Standards: Ensure the results meet the criteria set forth in SNI 8389:2017 for acceptance or rejection of the material.

Conclusion

Conducting a tensile strength test for reinforcing steel bars is essential for quality assurance in construction materials. By following the steps outlined in this guide, you can ensure accurate testing and compliance with national standards. For future tests, consider exploring variations in sample size or material type to broaden your understanding of tensile properties.