1 General Provisions
1.0.1 This standard is formulated in order to further normalize concrete test methods, improve concrete test accuracy and test level, as well as have an uniform test method of performance on concrete mixture in inspecting or controlling the quality of concrete work or precast concrete unit.
1.0.2 This standard is applicable to the ordinary concrete mixture performance test in the construction engineering, including sampling, sample preparation, consistency test, setting time test, bleeding and pressure bleeding test, apparent density test, air content test and mixing proportion analysis test.1.0.3 As for the tests carried out according to the test methods in this standard, the test report shall include the following contents:
1 The contents submitted by the client:
1) Name of the client;
2) Name of engineering and construction position;
3) Names of the to-be-inspected items;
4) Variety, specification and producing area of raw materials as well as concrete mixing proportion;
5) Other contents to be illustrated.
2 The contents submitted by the testing unit:
1) Sample number;
2) Test date and time;
3) Name, model and number of instruments and equipments;
4) Ambient temperature and humidity;
5) Variety, specification and producing area of raw materials, concrete mixing proportion and corresponding test number;
6) Mixing mode;
7) Concrete strength grade;
8) Test results;
9) Other contents to be illustrated.
1.0.4 Test method of performance on ordinary concrete mixture shall not only conform to the requirements of this standard, but also those in the current national compulsory standards.
2 Sampling and Sample Preparation
2.1 Sampling
2.1.1 The same group of concrete mixture shall be selected from the same tray or the same vehicle of concrete. The sampling amount shall be more than 1.5 times of the amount required in the test and should not be less than 20L.
2.1.2 The sampling of concrete mixture shall be representative, and multiple sampling methods should be adopted. Generally, samples are selected from 1/4, 1/2 and 3/4 respectively of the same tray or the same vehicle of concrete; interval between the first sampling and the last sampling should not exceed 15 minutes; then the samples shall be mixed uniformly with hands.
2.1.3 The interval between the end of the sampling and each performance test should not exceed 5 minutes.
2.2 Sample Preparation
GB/T 50080-2002 The following standards are cited：
