I. Product introduction: According to the industry standard JGJ/T234-2011, it is used to detect the compressive strength of building engineering masonry mortar. It has accurate and intuitive data. Easy to operate, etc.
Second, the main technical parameters
★ Pressure test range: 0-5000N, display unit: 1N
★Working voltage: 220V
★ Working temperature: 5-35 ° C is recommended to use at room temperature of 10-30 ° C
★ Repeatability error: ≤ ± 1%;
Third, the pressure gauge should meet the following technical requirements:
★ The overall structure should have sufficient strength stiffness;
★The diameter of the round flat head of the pressure selection instrument is (10±0.05)mm, and the rated stroke should not be less than 18mm;
★The pressure gauge should be equipped with a centering automatic leveling system;
★ The ultimate pressure of the pressure gauge should be 5000N;
★ The A small division value of the digital display reading system should not be greater than 1N, and the digital reading and reading system should have the peak hold function, the power off function and the data storage function;
★ The force value error of the force measurement system should not be greater than 1N.
★ The ambient temperature of the pressure gauge should be 5 °C ~ 35 °C. The digital reading system should be used and placed in the indoor natural environment. It is strictly prohibited to contact with water.
Fourth, the sampling method should meet the following requirements:
★ When the test object is part of a whole building or building, it can be divided into one or several independent detection units. When dividing the detection unit into the continuous wall, the height of each wall should not be greater than 3.5m, and the horizontal length should not be greater than 6.0m.
★ When there are more than 6 walls in each detection unit, the number of randomly sampled wall sheets should not be less than 6; when there is no more than 6 pieces in one detection unit, each wall should be tested within each wall. At least one measuring area should be used. When each wall is arranged with 2 or more side areas, it should be evenly distributed along the wall height. When the detection unit is only a single wall, the measurement area should not be less than two.
★ The area of each survey area should be 0.5m × 0.5m.
★ Six mortar specimens with an area of not less than 30mm×30mm and a thickness of 8mm～16mm should be randomly taken in the horizontal gray seam of each survey area. One of them should be the backup sample, and the other five should be the test. kind. Both sides of the specimen should be relatively parallel. The obtained samples should be collected and numbered in the same container.
★The mortar test should be taken within 20mm of the wall surface. It should not be drawn on the independent brick column or the wall with the length less than 1m, nor should it be extracted on the wall directly under the load beam.
5. The production of test pieces shall meet the following requirements:
★ The linear length of the small center of the test piece A should not be less than 30mm;
★ The pressure surface of the test piece should be flat and free of defects. For the uneven pressure surface, it can be sanded with sandpaper;
★ The sand and floating sink on the surface of the test piece should be removed.
★The mortar sample should be tested under natural dry condition; when the mortar sample is in a wet state, it should be dried or dried naturally.
★The thickness of the mortar test piece should be measured with a vernier caliper. The thickness measurement point should be within the pressure selective action surface. The reading should be accurate to 0.1mm, and the average thickness of the three different parts should be taken as the thickness of the test piece.
★ On the surface of the two indenters of the pressure gauge, a thin rubber pad with a thickness less than 1mm and a slightly larger area than the round flat head should be attached. To start the pressure gauge, set the digital reading and reading system to the peak hold state, and confirm that the unit of measurement is Newton (N).
★The mortar test piece should be placed vertically between the two indenters of the pressure tester. The distance from the edge of the pressure head to the edge of the mortar test piece should not be less than 10mm.
★ When loading the mortar test piece, the loading rate should be controlled at 1/15~1/10 of the estimated damage load per second, and should continue until the test piece is destroyed. The value of the pressure selection load shall be the peak value displayed by the digital selective reading system of the pressure gauge when the mortar specimen is damaged, and shall be accurate to 1N.