ASTM D5587
Trapezoidal Tear Test
Standard Test Method for Tearing Strength of Fabrics by Trapezoid Procedure - PDF
ASTM D5587 is a standardized test method used to determine the tear strength of fabrics using a trapezoid-shaped specimen. This method is commonly used for woven textiles, nonwovens, and coated fabrics to evaluate their resistance to tearing once a rip has begun. It’s particularly useful for fabrics where traditional tongue tear or Elmendorf tear methods may not yield consistent results.
In this article, we'll cover the scope of ASTM D5587, required test equipment, sample preparation, testing procedure, and the calculation of tear strength. We’ll also explore similar standards and typical applications.
What Is ASTM D5587?
ASTM D5587, titled "Standard Test Method for Tearing Strength of Fabrics by Trapezoid Procedure," provides a quantitative measure of tear resistance for fabric specimens that have been slit and pulled apart under tension. Unlike some tear tests that initiate tearing through pendulum impact or notch propagation, the trapezoid method uses a progressive tear format to simulate real-world tearing under stress.
This test method is ideal for fabrics that do not tear easily along warp or weft directions or when a bias angle is introduced during loading.
Scope and Applications
This method is commonly used for:
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Woven and nonwoven fabrics
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Technical textiles and composites
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Geotextiles
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Upholstery materials
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Protective garments
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Military and industrial textiles
The trapezoid tear method provides an accurate measure of resistance to tearing in applications where grip slippage, fraying, or irregular tearing might affect results using other test methods.
Test Specimen and Sample Preparation
Specimen Dimensions:
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Width: 76 mm (3.0 in)
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Length: 152 mm (6.0 in)
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Trapezoid Cut: A trapezoidal slit is cut into the center, typically 25 mm (1.0 in) long, and angled toward the edge to initiate the tear.
The specimens should be cut precisely, with the trapezoid tear line aligned consistently across all samples. Edges should be clean and not frayed. Samples should be conditioned at 21 ±1°C and 65 ±2% RH for at least 24 hours before testing (per ASTM D1776).
Required Testing Equipment
1. Universal Testing Machine (UTM)
Used to apply a controlled tensile load at a constant rate. The grips pull the two long sides of the trapezoid apart, propagating the tear through the material.
Recommended Specs:
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Load capacity: 1 kN to 5 kN
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Crosshead speed: 300 mm/min (12 in/min)
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Real-time force data acquisition
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High-precision load cell and software for peak force capture
2. Grips
Grips must be able to hold fabric securely without slippage. Pneumatic or mechanical grips with serrated or rubber-faced jaws are recommended.
3. Data Acquisition Software
The software should record and report the maximum force required to propagate the tear. It should also provide graphical output of force vs. displacement if needed.
ASTM D5587 Test Procedure
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Mount the Specimen
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Place the test specimen in the grips so the trapezoid shape is oriented properly.
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The slit edge should be centered between the jaws and aligned vertically.
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Begin the Test
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Start the machine and pull at a constant rate of 300 mm/min (12 in/min).
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The tear will begin at the cut and propagate through the trapezoid section.
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Record Results
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The peak load required to propagate the tear is recorded.
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A minimum of 5 specimens in both warp and fill directions should be tested for reliable results.
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Tear Strength Calculation
The tear strength is the maximum force recorded during the tearing process. This value is reported in:
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Newtons (N)
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Or Pounds-force (lbf)
No special formula is needed, as the peak force represents the tearing strength directly. Results should be reported as the average tear strength of all tested specimens, along with standard deviation.
Benefits of ASTM D5587 Testing
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Simulates real-world tearing from a small defect or rip
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Works well with coated or treated fabrics where traditional tear methods are unreliable
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Provides a repeatable and standardized method for quality control
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Useful for both production testing and R&D comparisons
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Eliminates problems with uneven or premature tearing seen in other test types
Related Standards
Other similar standards for fabric tear strength include:
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ASTM D5733 – Tearing strength of nonwoven fabrics using trapezoid method
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ASTM D1424 – Elmendorf tear test for textiles
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ISO 9073-4 – Tear resistance of nonwovens (similar to D5587)
Conclusion
ASTM D5587 provides a dependable and standardized method for evaluating tear strength in fabrics using a trapezoidal sample geometry. Whether you're testing technical textiles, military fabrics, or commercial upholstery materials, this method gives reliable data on how your material performs under tear stress.
Using a universal testing machine with the right grip setup and test procedure, you can quickly determine how your fabric will behave in demanding real-world conditions.
Looking for ASTM D5587 Test Equipment?
We supply complete systems, including universal testing machines, grip assemblies, and software configured for trapezoid tear testing. Contact us for application support or a turnkey testing solution.
Similar Specifications:
ASTM D2261 - Textile Tongue Tear Test
ASTM D5034 - Textile Tensile Test (Grab)
ASTM D5035 - Textile Tensile Test (Strip)
ASTM D5735 - Nonwoven Fabric Tongue Tear Test