The Vibropenetrator was developed by Komlos (1964) as a penetration test to measure the behavior of vibrated concrete. The device consists of a standard 20 cm cube mold mounted on a vibrating table. Concrete is placed in the mold and compacted with the assistance of the vibrating table. A rod, which is guided by a sleeve mounted to the cube mold, is placed on top of the concrete. The vibrating table is started and the time for the rod to penetrate a certain depth into the concrete is measured as an indication of workability. A ring on the rod touches the top of the sleeve to indicate the end point of the test. Komlos performed the test on moderate to highly workability concretes with water/cement ratios ranging from 0.38 to 0.90.

The Vibropenetrator test has the advantage of being a dynamic test that adds energy to the concrete. The results of the test are a function of not just the concrete properties, but also the nature of the applied vibration. Large coarse aggregates could interfere with the descent of the rod and distort test results.

• The Vibropenetrator test is a dynamic test that measures the behavior of vibrated concrete.
• The test is simple to perform and provides a direct result.
• Large coarse aggregates could distort test results by interfering with the descent of the penetrating rod.
• Although the test has been performed on a wide range of concrete workability, highly flowable concrete with a water cement ratio near 0.90 would likely be difficult to test with precision.
• The test requires a vibrator and electricity and is not as simple as other single-point field tests.