In general, the diameter of the drilled core sample should not be less than 3 times the maximum particle size of aggregate, and in any case, it should not be less than 2 times the maximum particle size of aggregate. The surface of each modified core sample needs to have the template surface of the component concrete protoplasm, so as to read the rebound value and carbonation depth before making the core sample specimen. It is impossible to cut a long core sample into several core samples along the length direction to calculate the correction coefficient.

Extended data:

Precautions:

1. Before mixing, the materials in the mixing yard shall meet the requirements of paving materials for 3~5 days.

2. Before paving every day, check the water content of aggregates in different parts of the site and calculate the mixture ratio of the day. The sum of added water and natural water content is slightly higher than the optimal water content by 65,438+0 percentage points.

3. After mixing every day, check whether the discharged material meets the design mixture ratio. After formal production, check the mixing situation every 1~2 hours, and check whether the mixture ratio and water content change. When working at high temperature, the water content in the morning and evening should be different from that at noon, and it should be adjusted in time according to the temperature change.

4, mixer unloading is not allowed to take the form of free fall, loader loading transportation, using direct loading transportation, unloading by hopper. When loading, the vehicle should be moved back and forth and loaded in three times to avoid segregation of the mixture.

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