Pull Test Methodology

Asphalt Anchors conducts rigorous pull testing to determine the rated holding strength of our anchor and adhesive systems. All testing is performed on representative asphalt installations to ensure real-world performance data.

Test Installation

Anchors are installed following manufacturer instructions and allowed to cure for a minimum of 24 hours before testing. Extended cure time testing (up to 6 months) has shown no significant variation in strength, confirming that anchors reach full strength within the initial cure period.

All tests are performed on professionally installed PG 64-16 asphalt, 3” thick over 3” compacted road base, aged approximately 1 year to simulate typical residential driveways.

Test Equipment & Procedure

We use a calibrated hydraulic jack with integrated pressure gauge mounted in a custom 3-point support stand. The stand measures 12” tall with legs spaced 18” apart in an equilateral triangular pattern. This configuration transfers the pulling force into the asphalt surface around the anchor being tested.

The anchor is threaded through the center of the jack. Force is applied gradually over approximately one minute while data is logged at 500ms intervals. Each test is video recorded for visual verification.

Measurement Points

Three critical data points are recorded for each test:

• First Movement: Force at 1/8” vertical displacement
• Major Movement: Force at 1/2” vertical displacement (considered functional failure)
• Ultimate Failure: Maximum force achieved before complete pullout

We use the Major Movement value as our primary performance metric, as this represents the point where an anchor would no longer reliably hold a load.

Rating Methodology

Each anchor size and adhesive combination is tested a minimum of 3 times, with many configurations tested 9 or more times to ensure statistical validity. The rated strength is calculated as 90% of the average Major Movement force across all tests, providing a conservative safety margin.

Individual test results, including specific anchor models, adhesive types, and detailed force data, are published separately with each product rating.

Temperature Considerations

Our temperature testing uses the PG64-16 pavement described above. Temperature measurements are grouped into 10°F buckets. A bucket label identifies a group of measurements; it does not mean every test occurred at exactly the labeled temperature.

For each anchor model, we calculate the average pull capacity in the 70°F bucket and use it as that model’s 100% reference. Results in higher-temperature buckets are divided by the same model’s reference average before models are compared. This prevents differences in anchor size and baseline strength from obscuring the temperature effect.

The 120°F bucket is the highest tested so far. Each anchor model’s average normalized pull capacity at 120°F fell between 58% and 62% of its corresponding 70°F reference. We do not extrapolate the result above the measured range or use it as a universal correction for other pavement.

Binder grade, mix characteristics, pavement condition, load duration, and the temperature through the anchor depth can all affect performance. See High Pavement Temperature and Anchor Capacity for the measured result, an SP10 example, and guidance on applying the information.