The schmidt hammer provides a quick and inexpensive measure of surface hardness that is widely used for estimating the mechanical properties of rock material. Isrm suggested method isrm suggested method for determination. A schmidt hammer measures the compressive strength and elastic properties of concrete and rock. The type n schmidt hammer is pressed against the concrete structure and the rebound values are displayed on a mechanical sliding scale. The original schmidt os8000 is the original concrete test hammer, now digitally redefined and it is also the most advanced rvalue hammer ever made, with unmatched performance, ease of use, and versatility, as well as reporting on the go thanks to its mobile app. Rebound hammer test rebound hammer test is done to find out the compressive strength of concrete by using rebound hammer as per is. Pdf application of rebound hammer method for estimating. We provided accuracy and assurance for significant. A schmidt hammerswiss hammerrebound hammer invented by ernst schmidt in 1948, a swiss engineer, is a mechanical device used to measure. Concrete testing with original schmidt hammer is the most frequently used method worldwide for nondestructive testing of concrete and structural components. Procedure to determine strength of hardened concrete by rebound hammer.
A free powerpoint ppt presentation displayed as a flash slide show on. Contents principle of rebound hammer test working of rebound hammer test limitations of rebound hammer test disadvantages of rebound hammer this is one of the oldest nondestructive tests and it is still widely used. Digischmidt concrete test hammer, type nd consisting of. Return package must be in the original packaging, everything must be in new condition. To ensure uniformity, the following procedures were consistently observed for the rebound hammer test. Concrete test hammers swiss precision since 1954 the concrete test hammers are the most widely used portable ndt measuring instruments for a rapid assessment of the condition of a concrete structure. Rebound hammer test procedure for concrete hardness. Bureau of indian standard did not published any standard for this test upto 1991. Each hammer is designed for specific test applications.
The rebound hammer has been around since the late 1940s and today is a commonly used method for estimating the compressive strength of inplace concrete. It is designed for testing concrete within a compressive strength range of 1,450 to 10,152 psi 10 to 70 nmm 2 and impact energy of the test is 1. Digischmidt 2000 nd test equipment pdf manual download. Rebound values are read from a scale for subsequent calculation of the mean. It provides a rapid, nondestructive method of quickly assessing the condition of concrete structures. Standard test method for rebound number of hardened concrete1. Yasar and erdogan 2004a derived the following empirical correlation between them based on the test results of six different rock types. Rebound hammer test, schmidt hammer test, nondestructive. Digi schmidt concrete test hammer, type nd consisting of. The underlying principle of the rebound hammer test is. Utc3032 concrete test hammer original schmidt type n proceq is used to measure the compressive strength characteristics of hardened concrete nondestructively, control uniform concrete quality and detect weak spots in the concrete. The concrete test hammer is not allowed to be operated by children or anyone under the influence of.
Application of rebound hammer method for estimating compressive. Supplied complete with carrying case and carborundum stone, the hammer is suitable for testing concrete with compressive strengths of 10 to 70 nmm2. Original schmidt concrete test hammer n type proceq non. You will hear a click, and the piston will extend into the test position. Type n hammer is also used for the testing of massive rock. Missing parts or anything in original condition, otherwise it will not qualify. Substrate requirements, compressive and cohesive testing. Note in view of the limitations of each method of nondestructive testing of concrete, it is essential. Schmidt hammer test pdf estimate the compressive strength of concrete is the rebound hammer test, also known as schmidt hammer test. Pdf the schmidt hammer in rock material characterization.
Surface hardness measured during the test give an idea about the soundness and quality of cover concrete. The functionality of the rebound hammer shall have been verified in accordance with 6. Method of non destructive testing of concretmethods of test, part 2. Hm75 original schmidt concrete test hammer is the classic rebound hammer known for its accuracy, repeatability, and longevity. Review of the rebound hammer method estimating concrete.
Perform a few test impacts with the concrete test hammer on this smooth, hard sur face before taking any measurements which you are going to evaluate. After impact, maintain pressure on the instrument and, if necessary, depress the button on the side of the instrument to lock the plunger in its retracted position. Jul 08, 20 we believe in serving products of quality. Testing services rebound hammer rebound hammer test is done to find out the compressive strength of concrete by using rebound hammer as per is. Using the humboldt concrete rebound hammer always hold the concrete rebound hammer in both hands while in use. Various empirical correlations have been proposed for estimating the. Reliability of rebound hammer test in concrete compressive. Concrete test hammers original schmidt idm instruments. Part 2 rebound hammer 1 scope this standard covers the object, principle, apparatus and procedure of rebound hammer test method. Rebound hammer test on concrete principle, procedure.
Operating principle of the rebound hammer physical principle the test hammer rebound hammer is intended to measure the surface hardness of concrete and there is an. The compressive strength test that is conducted with the aid of a schmidt hammer is also known as a rebound hammer test. Original schmidt concrete test hammer n type proceq. A schmidt hammer, also known as a swiss hammer or a rebound hammer or concrete hammer test, is a device to measure the elastic properties or strength of concrete or rock, mainly surface hardness and penetration resistance. The compressive strength test that is conducted with the aid of a schmidt hammer is. In the present paper, a critical approach to the evaluation of schmidt hammer testing is attempted. Snell, pe senior materials engineer, western technologies inc. Using the schmidt hammer on rock mass characteristic in. Ppt concrete rebound hammer powerpoint presentation. Type n schmidt test hammer the type n hammer is designed for testing concrete items 4 100 mm or more in thickness, or concrete with a maximum particle size less than or equal to 1.
This procedure is recommended in all guidelines and relevant international standards. In addition, influence of test conditions and some general guidance on the interpretation of test results are also given. Aug 24, 2016 contents principle of rebound hammer test working of rebound hammer test limitations of rebound hammer test disadvantages of rebound hammer this is one of the oldest nondestructive tests and it is still widely used. Sep 19, 2014 rebound hammer test rebound hammer test is done to find out the compressive strength of concrete by using rebound hammer as per is. Procedure for schmidt hammer test or rebound hammer test. View and download proceq digischmidt 2000 nd operating instructions manual online. The rebound schmidt hammer is one of the oldest and best known methods of comparing the concrete in various parts of a structure and indirectly assessing concrete strength.
Rebound hammer test schmidt hammer testing on concrete. The hammer is intended for testing the quality of concrete in finished structures such as buildings and bridges. Schmidt hammer method is the most widely used nondestructive method for assessing concrete quality. This device is universally used because of a hardened steel hammerimpacted on the concrete by a spring. Gradually push the instrument toward the test surface until the hammer impacts.
If the situation demands,the rebound hammer can be. Put the rebound hammer back together, and test it on the anvil again to get a calibrated reading. It was invented by ernst schmidt, a swiss engineer. Pdf the rebound hammer strength test, being a nondestructive test, has its advantages of preserving integrity of sample. Standard test method for rebound number of hardened concrete. Isrm suggested method isrm suggested method for determination of the schmidt hammer rebound hardness. Estimating the strength of concrete using surface rebound. Standard test method for determination of rock hardness by rebound hammer method1 this standard is issued under the. It was devised in 1948 by ernst schmidt, and is therefore. The schmidt hammer rebound test has been briefly described in chapter 3. The test can thus be conducted horizontally on vertical surfaces or vertically upwards or downwards on horizontal surfaces.
The concrete test hammer is a mechanical device used. Test hammer, display unit, test hammer cable, transfer cable, grinding stone, carrying strap, operating instructions and carrying casethe schmidt hammer digischmidt was developed for the non destructive measurement of the concrete compressive strength and controlling the uniform concrete quality. Rebound hammer is also known as schmidts hammer or swiss hammer as it is invented by ernst schmidt, a swiss engineer. Concrete test hammer, ideally suited for onsite tests of concrete and is widely used instrument for analyzing the uniformity and compressive strength characteristics of concrete structures and detection of weak spots in the concrete. The advantage of this method can practically to assess the. Astm c805 c805m 18 standard test method for rebound. The silverschmidt is an integrated electronic schmidt hammer, featuring greater ease of use and. The original schmidt, the worlds first and now most widely used test hammer for. All bsi british standards available online in electronic and print formats. Hammer type, test range and calibration the earlier isrm suggested method 1 endorsed the use of only the ltype sh. Before starting the procedure calibration of the hammer is required. Through a statistical analysis of field measurements on sandstone blocks from the archaeological site of delphi greece, it was shown that there is an inconsistency in the correction method proposed by the manufacturer, in relation to the direction of rebound.
Proceq digischmidt 2000 nd operating instructions manual pdf. Proper use of the rebound hammer updated to reflect the. Standard test method for rebound number of hardened. Concrete testing with the original schmidt hammer is the most frequently used method worldwide for nondestructive testing of concrete and structural components. Schmidt hammer test or rebound hammer test of concrete. The surface of hardened concrete is struck with the hammer, and concrete compressive strength is estimated via the surface hardness rebound value. Using the schmidt hammer on rock mass characteristic in sedimentary rock at tutupan coal mine. Nov 19, 2016 a schmidt hammer swiss hammer rebound hammer invented by ernst schmidt in 1948, a swiss engineer, is a mechanical device used to measure surface hardness and penetration resistance strength of. Standard test method for determination of rock hardness by. Save page to pdf the page to pdf system has been restored. A schmidt hammer is also known as a rebound hammer or a swiss hammer.
Schmidt hammer test outcomes demonstrated more reliably results when compared with the. Most widely used tester for measuring paper roll hardness test results based on the type l schmidt hammer hardness value which conforms to tappi t 834 digital hammer with digital reporting and data sharing via a free, comprehensive apple ios app standalone analog hammer use it offline and download data to the app later. For taking a measurement, the rebound hammer should be held at right angles to them surface of the concrete member. The rebound of an elastic mass depends on the hardness of the surface against which its mass strikes. Ceyhan limestone, barbaros marble, antique cream limestone, osmaniye marble, toprakkale basalts, and handere sandstone. Pdf rebound hammer test method statement rusi sumdaram. Proceqs schmidt hammer portfolio is the most comprehensive available. Schmidt rebound hammers, concrete test hammers, ndt concrete. Standard test method for rebound number of hardened concrete1 this standard is issued under the. Supplied complete with carrying case and carborundum stone, the hammer is suitable for testing concrete with compressive strengths of. A number in parentheses indicates the year of last reapproval. Test hammer, display unit, test hammer cable, transfer cable, grinding stone, carrying strap, operating instructions and carrying casethe schmidt hammer digi schmidt was developed for the non destructive measurement of the concrete compressive strength and controlling the uniform concrete quality. Locations having very low rebound numbers indicate weak surface concrete and may be affected by corrosion.
Concrete test hammer type lb schmidt concrete impact. Astm c805, standard test method for rebound number of hardened concrete, summarizes the procedure as a steel hammer impacts, with a predetermined. Aug 26, 2019 a schmidt hammer measures the compressive strength and elastic properties of concrete and rock. Schmidt rebound hammers, concrete test hammers, ndt. Schmidt hammer rebound number is higher as density or unit weight increases. A simple equipment known as rebound hammer or schmidt hammer is used for this purpose. Lianyang zhang, in engineering properties of rocks second edition, 2017.
Nondestructive testing of concrete by rebound hammer. C805 c805m18 standard test method for rebound number of hardened concrete rebound number insulating boards springdriven steel hammers. A number in parentheses indicates the year of last. The test determines the greatest perpendicular force in tension that a surface area can bear before a plug. In the procedure of rebound hammer test, the plunger of rebound hammer is pressed on the surface of concrete, so that a spring controlled mass with a constant energy is made to hit the concrete.
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