The Silver Schmidt Live is the latest version of Proceq's Q Value Rebound Hammer. Schmidt hammers are most commonly used for evaluating the strength and uniformity of concrete. Part of the Live instrument family from Proceq, the new iOS and Android application records measurements and supports instant reporting and information sharing between users.
Classical rebound hammers are often used to evaluate the strength of in-situ concrete, but such hammers suffer from the following insufficiencies:
1. The rebound value is dependent on the impact direction.
2. The rebound value is affected by internal friction.
3. Limited tightness of sealing causes premature loss of accuracy.
The unique design and high quality construction of the Silver Schmidt address all of these issues and makes Schmidt hammer testing quicker and more accurate than ever before.
Conversion curves are provided for a wide range of concrete compressive strength, including low and high strength concrete fc <10 MPa (5MPa using Mushroom Head) and up to 100MPa.
The iOS and Android application supports visual report generation with lists, bar charts and statistical information. Single or multiple series can be exported to .csv or as a .pdf report.
The Logbook function allows the operator to make notes, take photos and records his GPS geolocation with each measurement series.
Type L hammers strike with a lower impact energy and are suitable for testing of thin concrete sections and where the hammer is to be used primarily for low strength concretes down to 10mpa.
If concrete is softer than this the Mushroom Head accessory spreads the impact over a wider area and is suitable for testing concrete strengths as low as 5mpa.
The Rock Schmidt is a dedicated version of the Silver Schmidt for rock testing applications, including correlations to unconfined compressive strength (UCS), youngs modulus and weathering grade.
The classic "R"-value is the mechanical travel of the mallet on rebound. It is affected by its friction on the guide rod, the friction of the gauge, gravity, the relative velocity between unit and mechanical parts. This is true for all concrete test hammers currently on the market.
The Silver Schmidt acquires the "Q"-value by measuring the velocity (V) of impact and of rebound immediately before and after the impact. The "Q"-value need not be corrected for impact direction. There is a
The "Q"-value [=rebound V divided by inbound V] represents the physical rebound coefficient. It is virtually free of all the above error sources. It is thus the indicator of choice to be used as a basis to convert to compressive strength.
The lightweight hybrid design of the impact plunger is made from aerospace alloy, matched to the elastic properties of the concrete and equipped with a hardened steel cap. Independent validation testing by BAM in Berlin has shown the Silver Schmidt to have less dispersion than the classical hammer over the entire range.
Proceq's Schmidt Live web based reporting tool allows operators and their colleagues to review data collected in the field with a Silver Schmidt Live. It presents the measurements, statics and conversion into engineering units. The Logbook details can also be reviewed.
A lower 10th percentile curve is recommended by the major standards EN 13791 and ASTM C805/ACI 228.1 to provide a safety margin to take into account the various factors that may affect the in-situ tests. 90% of the data pairs lie above the curve and 10% lie below. This curve is intended to give a conservative estimate in those cases that the hammer is not calibrated for the specific mix under test. For older hammers firmware release v1.0.3 adds the new curve to your hammer.
Data collection and processing of test results comply with major industry standards: EN 12504-2, ENV 206 ASTM C805, ASTM D5873 (Rock), BS 1881, part 202
The Silver Schmidt Live is available as a package combining the best in class hardware OS82000 and a 5 year subscription to the OS app. The App subscription may be continued after 5 years, or alternatively the Schmidt Hammer may be used only as a stand a lone device. This package also includes a 5 year electrical 6 month mechanical warranty.