Review meeting of CCPA standards Setting and Strength Accelerating Admixture for Sprayed Concrete and Test Method for Compressive Strength of Young Sprayed Concrete was held by CCPA and CBMF on November 15, 2023. 27 representatives from research and architectural design institutes, colleges and universities, industry associations, inspection body and laboratory, production enterprises and users attended the meeting, of which 15 were members of review committee.

The main drafter of the two standards introduced the standard preparation process, the collection of comments and the test data that support the main technical requirements in the two standards respectively. The review committee reviewed all the documents, examined the standard text word by word and put forward revisions. The review committee made conclusions that technical indexes of both the two standards are advanced and applicable, the test methods are operable and they both reach international advanced level in general. Finally, the two CCPA standards were approved by unanimous approval.

Setting and Strength Accelerating Admixture for Sprayed Concrete clarifies the definition and classification of setting and strength accelerating admixture for sprayed concrete, and proposes indicators such as hourly strength, which is a supplement and improvement to the current national and industry standard system. The implementation of this standard is of great significance for standardizing the quality of early strength admixtures used in sprayed concrete in China, and improving the quality of sprayed concrete and mortar engineering.

Test Method for Compressive Strength of Young Sprayed Concrete fully considers the anisotropy of mechanical properties caused by the penetration method of sprayed concrete measuring nails, clarifies the layout of measuring points for the mechanical properties of sprayed concrete, proposes the working principle of a penetration type concrete strength tester, and establishes a method for measuring the compressive strength of sprayed concrete using the penetration method. This standard supplement the strength testing method for sprayed concrete, which is of great significance for ensuring the quality and safe construction of sprayed concrete engineering.