(1) the varieties of admixtures should be selected according to the requirements of engineering design and construction, and determined through tests and technical and economic comparison.
(2) the admixture mixed into concrete, shall not harm human body, shall not pollute the environment.
(3) Portland cement, ordinary Portland cement, slag Portland cement, volcanic limestone Portland cement, fly ash Portland cement and composite Portland cement should be used for concrete cement mixed with admixtures, and the adaptability of the admixtures to cement should be tested and can be used after meeting the requirements.
(4) admixtures for concrete materials such as cement, sand, stone, admixtures, admixtures should meet the requirements of the current national standards.
Try to match admixture of concrete, the use of the raw materials of engineering should be adopted, and with the construction of the same environmental conditions, the test items according to the requirement of design and construction, such as slump and slump after the change, when the setting time, strength, air content, shrinkage, expansion rate, etc., as the raw materials used in engineering or concrete performance requirements changes, should try to match experiment was carried out again.
(5) different varieties of admixtures used, should pay attention to its compatibility and the impact on the performance of concrete, should be tested before use, meet the requirements can be used.
polycarboxylate superplasticizerare materials that are mixed in the mixing process of concrete and can improve the performance of concrete according to requirements.
The varieties of admixtures should be selected according to the main purposes of using admixtures and determined through technical and economic comparison.
The amount of polycarboxylate superplasticizer should be determined by test according to its varieties and according to the use requirements, construction conditions, concrete raw materials and other factors.
The amount of admixtures (calculated as solids) shall be expressed as a percentage of the weight of cement, and the weighing error shall not exceed 2% of the prescribed measurement.
The coarse and fine aggregate used shall conform to the relevant national standards currently in force.
The production and use of concrete mixed with admixtures, but also should accord with the country's current concrete admixtures quality standards and relevant standards, norms.
