Geosynthetics hydrostatic pressure tester based on SL/T235-1999, JTGE50-2006,
GB/T19979.1-2005 Geosynthetics anti-seepage performance. National standard R & D and design of hydrostatic pressure resistance. Applicable to the measurement of impermeability of various geotechnical materials, stable performance, convenient and practical.
Geosynthetics resistance to hydrostatic pressure tester technical parameters:
★ accuracy 0.5%
★Perforated plate through hole ф3mm
★Perforated plate diameter ф200mm
★A large pressure 2.5MPa
★ sample size ф200mm, effective cross-sectional area ≥ 200 square centimeters
★ pressure pump automatic water supply, voltage 380v
★ Pressure adjustment range: 0~2.5MPa
★Outer size: 600X750X1200mm
★ Machine weight: 150Kg
Geosynthetics resistance to hydrostatic tester use:
★ Pressure setting: press the set button “Back” after power on, press the shift button “>” and then press the adjustment buttons “+” and “--” to adjust the value. After adjusting, press the set button “Back” to save . After adjusting the lower limit value, press the set key to exit. The 8-hour lower limit rises to 0.1 MPa. Time clear: Re-do the experiment, keep pressing the “--” button to not release, first display the time value, after 10 seconds, the time can start from 0 hours, “!” can not be mistakenly pressed during work. ★ Time review: Press “—” to change the pressure to hour, the upper limit is minute and the lower limit is second. Return to pressure display after 30 seconds
★ Zero adjustment: If there is no pressure after starting, if it does not return to zero, press once to set zero. Do not press the clear button when there is pressure, and then zero after releasing.
★ Open the water injection cover and add pure water. When the water tank is full, start the pressure and open the pressure regulating valve to make the water flow into the high pressure chamber chassis to just overflow.
★ Place the sample without wrinkles on the net inside the water collector, overflow excess water to ensure no air bubbles in the clamp; cover the porous plate and evenly clamp the sample.
Geosynthetics resistance to hydrostatic tester operating procedures
★ Slowly adjust the inlet valve to increase the water pressure in the clamp to 0.1 MPa. If the approximate range of the hydrostatic pressure of the sample can be estimated, the water pressure can be directly added to the lower limit of the range to start the test. While maintaining the above pressure for at least 1 h, it was observed whether or not water permeated in the pores of the perforated plate. If the sample is not water-permeable, pressurize step by step with a step of 0.1MPa, and each stage shall be kept for at least 1h until water seeps out, indicating that the sample has water seepage holes or cracks have occurred. The hydrostatic pressure resistance of the sample is accurate to 0.1 MPa. .
★ If the device specified in GB/T19979.2 is used, it is judged whether water seepage is caused by the seepage flow rate. When the seepage flow is very small under a certain hydraulic pressure difference, it can be considered that there is no water seepage. When the seepage flow increases rapidly, it indicates that the sample has water seepage holes or damage has occurred, and the test can be terminated.
★When water droplets appear in the hole of the perforated plate, if there is no water seeping out after wiping it off, it can be judged that this is caused by the overflow of the edge of the sample, and the test can be continued; if it is wiped off, there is still water. Exudation can be judged to be caused by water seepage of the sample, and the test can be terminated. If it is only necessary to judge whether the sample reaches a certain hydrostatic pressure value, it can be directly pressurized to this pressure value for at least 1 h. If there is no water seepage, it is judged to meet the requirements. The rest of the sample was measured for hydrostatic pressure resistance according to the procedure. If the three values differ greatly (the lower two values differ by more than 50%), the test specimen should be added.
★ The A value in the measured hydrostatic pressure values of the above three samples is taken as the hydrostatic pressure resistance value of the sample; if the measured value exceeds 3, the average value of the two values of A is as follows: If it is lower and lower than the lower low value by more than 50%, the value should be discarded.
Note: For specimens composited from textile materials and membranes, one side of the membrane should be facing the water surface; for composite materials with textile surfaces on both sides and the membrane in the middle, the specimen can be clamped to the side of the water surface. Part of the textile material is carefully peeled off, and a corresponding adhesive such as glass glue may be applied to the corresponding portion to ensure that the clamped portion does not leak water.