Test method:

1. Prepare Marshall specimens that meet the requirements, and the number of a group of specimens shall not be less than 4.

2. Measure the diameter and height of the specimen, measure the diameter of the middle part of the specimen with calipers, and measure the height with Marshall height tester or calipers in four directions of cross symmetry, with an accuracy of 65438±00mm from the edge of the specimen, and take its average value as the height of the specimen. If the height of the specimen does not meet the requirements of 63.5 mm 1.3 mm or 95.3mm 2.5mm, or the height difference between the two sides is greater than 2mm, the specimen is invalid.

3. Adjust the thermostatic water tank to the required test temperature. For viscous petroleum asphalt or emulsified asphalt mixture solidified in the oven, the test temperature is 60℃ 65438 0℃.

4. Put the upper and lower pressure heads of Marshall tester into a sink or oven to reach the same temperature. Take out the last ram from the sink or oven and clean the inside. In order to make the upper and lower pressure heads slide freely, a small amount of butter can be coated on the guide rod of the lower pressure head. Then take out the test piece and put it on the lower indenter, cover the upper indenter, and then install it on the loading equipment. Place the steel ball on the ball seat of the upper pressure head and align it with the pressure head of the load measuring device.

Test steps:

1. Keep the sample in a constant temperature box with specified temperature. The heat preservation time of standard Marshall specimen is 30 ~ 40 minutes, and that of large Marshall specimen is 45 ~ 60 minutes. There should be a gap between the specimens, and the bottom should be padded, not less than 5cm from the bottom of the container.

2. When using the automatic Marshall tester, connect the pressure sensor of the automatic Marshall tester with the computer or X-Y recorder correctly, and adjust the appropriate magnification. Adjust the computer program or aim the stylus of the X-Y recorder at the origin.

3, start the loading equipment, make the record bear the load, the loading speed is 50 mm/min 5 mm ... The computer or X-Y recorder automatically records the pressure of the sensor and the deformation curve of the sample, and automatically stores the data in the computer.

4. When the test load reaches the maximum, remove the flowmeter, and read the dial indicator in the pressure ring and the flow meter of the flowmeter.

5. The difference between the immersion Marshall test method and the standard Marshall test method is that the specimen is kept in a constant temperature water tank at a specified temperature for 48h, and the rest are the same as the standard Marshall test method.