Review meeting of CCPA standard Technical Specification for Control of Cracking in Cast-in-situ Concrete Structures was held by CCPA and CBMF in Beijing on April 7. 29 representatives from research and architectural design institutes, industry associations, ready mixed concrete producers, construction companies and users attended the meeting, of which 15 were members of review committee.

The main drafter of the standard introduced the standard preparation process, the collection of comments and the test data that support the main technical requirements in the standard. The review committee reviewed all the documents, examined the standard text word by word and put forward revisions. The review committee makes conclusions that the standard technical indexes are advanced and applicable, the test methods are operable and it reaches the domestic advanced level in general. Finally, this CCPA standard was approved by unanimous approval.

On the basis of domestic investigation and basic verification test, Technical Specification for Control of Cracking in Cast-in-situ Concrete Structures summarizes the research results and engineering practice experience of cracking control of cast-in-place concrete structures in recent years in China, and uses foreign advanced technology for reference to standardize the structural design, material requirements and cracking control in construction process of cast-in-place concrete for industrial and civil buildings. For the first time, the standard proposes that the paste to aggregate ratio and aggregate content should be taken as the key parameters of concrete mix proportion design when considering cracking prevention. Moreover, full-scale model tests were newly introduced into the cracking control during construction. This standard also puts forward the requirements of crack resistance calculation and setting induced joints in the sensitive parts or areas of concrete structures in the construction stage, and makes it clear that cracking sensitivity is an important index for selecting cement. The implementation of this CCPA standard will have important guiding significance for improving the construction quality of cast-in-place concrete.