Standard Test Method for Fundamental Transverse, Longitudinal, and Torsional Resonant Frequencies of Concrete Specimens. A non-destructive sonic method. Fundamental Transverse, Longitudinal, and Torsional Resonant Frequencies of Concrete Specimens. All the Controls products ASTM C standard. Enter now!.
|Published (Last):||22 June 2014|
|PDF File Size:||1.82 Mb|
|ePub File Size:||19.8 Mb|
|Price:||Free* [*Free Regsitration Required]|
Geotest Catalog Request Catalog. ASTM C, C The Geotest Sonometer is one of several devices now being offered for determining changes in resonant frequency of concrete specimens subjected to alternate cycles of freezing and astj with C Freeze-Thaw Apparatus.
Geotest Product Information
This apparatus closely follows design parameters set c251 over 40 years ago by the Portland Cement Association research laboratories. The original PCA design has been modified by changing to solid state circuitry and addition of a built-in cathode ray oscilloscope. No other resonant frequency system includes an oscilloscope despite being strongly recommended in ASTM C paragraph 4. Other systems offer an oscilloscope connection. The oscilloscope confirms that peak reading on meter is actual resonance and not a harmonic.
The apparatus consists essentially of a driver and pickup circuit.
Electrical power is converted by the driver into mechanical vibrations and these vibrations are imparted to the specimen under test. The actual frequency is displayed on a built-in digital counter.
Resonant frequency can be determined by watching the voltmeter reach its highest point.
The oscilloscope verifies resonance because the meter alone also reaches high points on harmonics. When resonance occurs, the actual number is digitally displayed on the frequency counter.
The Geotest Sonometer is the only system using a phono type cartridge as a pickup. All other units use accelerometers which require intimate contact with the test specimen.
Changing accelerometer positions on the test specimen is time consuming. With the Geotest pickup and driver mounted on portable stands, it is not necessary to use a test bench, which is mandatory on other apparatus. This allows for greater flexibility in testing.
A very detailed instruction manual accompanies each sonometer. The chassis measures 17x14x11″. C Rapid Freeze-Thaw Apparatus.
This item is part of the following categories: Geotest Instrument Corporation S.