Search results
Results from the WOW.Com Content Network
The test hammer hits the concrete at a defined energy. Its rebound is dependent on the hardness of the concrete and is measured by the test equipment. By reference to a conversion chart, the rebound value can be used to determine the concrete's compressive strength. When conducting the test, the hammer should be held at right angles to the ...
A procedure for ultrasonic testing is outlined in ASTM C597 - 09. [9]In India, till 2018 ultrasonic testing was conducted according to IS 13311-1992.From 2018, procedure and specification for Ultrasonic pulse velocity test is outlined in IS 516 Part 5:Non destructive testing of concrete Section 1:Ultrasonic Pulse Velocity Testing.
The modulus of elasticity of concrete is relatively constant at low stress levels but starts decreasing at higher stress levels as matrix cracking develops. The elastic modulus of the hardened paste may be in the order of 10-30 GPa and aggregates about 45 to 85 GPa. The concrete composite is then in the range of 30 to 50 GPa.
The characteristic strength is defined as the strength of the concrete below which not more than 5% of the test results are expected to fall. [ 16 ] For design purposes, this compressive strength value is restricted by dividing with a factor of safety, whose value depends on the design philosophy used.
There are different scales, denoted by a single letter, that use different loads or indenters. The result is a dimensionless number noted as HRA, HRB, HRC, etc., where the last letter is the respective Rockwell scale. Larger numbers correspond to harder materials. When testing metals, indentation hardness correlates linearly with tensile ...
A hardness number is just a semi-quantitative indicator of the resistance to plastic deformation. Although hardness is defined in a similar way for most types of test – usually as the load divided by the contact area – the numbers obtained for a particular material are different for different types of test, and even for the same test with ...
Usually measured from the concrete soffit formwork to the underside of the tendon duct or sheathing.. tendon number The identifying number given to a specific tendon within the set of tendons installed into the structure. tendon profile The physical path taken by a tendon between its end anchorages. [2]: 28 [3]: 9 tendon spacing
The Leeb Rebound Hardness Test (LRHT) invented by Swiss company Proceq SA is one of the four most used methods for testing metal hardness. This portable method is mainly used for testing sufficiently large workpieces (mainly above 1 kg). [citation needed] It measures the coefficient of restitution. It is a form of nondestructive testing.