According to the standard of concrete strength inspection and evaluation GB/T 50 107-20 10.
There may be smaller ones in the test block, such as c2 1. For such control ability, the assurance rate of concrete strength is very low, which can not meet the requirements of the specification (95% assurance rate). For example, the next test blocks are all pressed out around 63. Description. You have great control. It is considered that the strength of concrete meets the requirements.
Extended data:
According to Article 3.0.2 of the Standard for Inspection and Evaluation of Concrete Strength (GBJ 107-87), each group should sample three specimens from the same plate of concrete. The determination of its strength representative value shall meet the following requirements:
Take the arithmetic average of the strength of three specimens as the strength representative value of each group of specimens; ?
When the difference between the maximum or minimum strength and the median value in a group of specimens exceeds the median value 15%, the median value is taken as the strength representative value of the group of specimens;
When the difference between the maximum and minimum values of strength in a group of specimens and the median value exceeds 15% of the median value, the strength of the group of specimens should not be used as the basis for evaluation.
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