This standard is issued under the fixed designation C ; the number 1 This test method is under the jurisdiction of ASTM Committee C-9 on Concrete. Purchase your copy of ASTM C – 15 as a PDF download or hard copy directly from the official BSI Shop. All BSI British Standards available. mm. Thickness Measurement by ASTM C Accurate measurement of thickness requires knowledge of the in-place P- wave speed. ASTM C, “Test .
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These notes and footnotes excluding those in tables and figures shall not be considered as requirements of the standard. If the interface between the concrete and subgrade is rough, the amplitude spectrum will have a astj peak instead of a sharp peak associated with a flat surface. It is seen that at a concrete-air interface, there is complete reflection of the P-wave.
ASTM C1383 – 15
This is because the wave has c133 travel a longer distance as it diffracts around the flaw. Xstm Spider multiple impactor unit can be purchased as an option to increase the operating range of the systems.
Detection of Internal Defects The P-wave generated by impact will reflect at interfaces within the concrete where there is a change in acoustic impedancewhich is defined as the product of the density and wave speed of a material.
Powered by WordPress Theme Designed by: The thickness T of the member is related to this thickness frequency f and wave speed Cp by this simple approximate equation see below: Accurate measurement of thickness requires knowledge of the in-place P-wave speed.
These drawbacks are eliminated by using the impact-echo method, which requires access to only one surface. With the LONGSHIP two-transducer assembly, the transducers are placed mm apart and the impactor is about mm from one of the transducers one the line passing through the c133.
ASTM C Standard
The DOCter comes in two versions: Proceed to Checkout Continue Shopping. Olson offers Impact Echo systems for use with three different platforms as shown in the chart below. It is the responsibility of the user of this standard to establish appropriate safety and health practices and c13383 the applicability of regulatory limitations prior to use.
In impact-echo testing, the P-wave is used to obtain information about the member. Already Subscribed to this document. Please first log in with a verified email before subscribing to alerts. The figure below the waveform is the amplitude spectrum obtained by transforming the waveform into the frequency domain.
The equation on page 50 adtm used to solve for Cpi. You may delete a document from your Alert Profile at any time. No other units of measurement are included in this qstm. The P-wave speed is calculated by dividing the distance between the two transducers by the travel time.
Impact Echo IE investigations are performed to assess the condition or thickness of slabs, beams, columns, walls, pavements, runways, tunnels, and dams.
The DOCter is a versatile, portable system based on the impact-echo method, and can be used for the following applications: Measure the thickness of pavements, asphalt overlays, slabs-on-ground and walls Detect the presence and depth of voids and honeycombing Detect voids below slabs-on-ground Evaluate the quality of grout injection in post-tensioning cable ducts Integrity of a membrane ast an asphalt overlay protecting structural concrete Delamination surveys of bridge decks, piers, cooling towers and chimneystacks Detect debonding of overlays and patches Detect ASR damage and freezing-and-thawing damage Measure the depth of surface-opening cracks Estimate early-age strength development with proper correlation Principle A short-duration stress pulse is introduced into the member by mechanical impact.
Impact-Echo TestThis procedure measures the frequency at which the P-wave generated by a short-duration, point impact is reflected between the parallel opposite surfaces of a plate. DOCter Purpose The use of traditional stress wave methods, such as ultrasonic through transmission, to identify the presence of anomalies in structures requires access to both faces of a member.
The DOCter can also be used to measure the depth of surface-opening cracks, using a time domain analysis.
Besides thickness determination and flaw detection, the DOC can be used to estimate the depth of surface-opening cracks. The P-wave is then reflected back into the member and the cycle begins again. Need more than one copy? If the area of the reflecting interface is large, the impact-echo response will be similar to that of a solid plate except that the thickness frequency will be shifted to the higher value corresponding to the depth of the interface.
This assumes that ast, P-wave speed is uniform with depth. Detection of delaminations and honeycomb in sewer pipe.
NDT System Add-On — Impact Echo
This standard is not included in any packages. Complete Docter Brochure Docter Publications. Atsm makes the impact-echo method inherently powerful for detecting air interfaces, such as those due to delaminations, cavities, and honeycombed concrete.
There is a certain level of systematic error in the calculated thickness due to the discrete nature of the digital records that are used.