by From March to June 2022, the Beijing Municipal Commission of Housing and Urban Rural Development, in accordance with the requirements of the Notice on Further Strengthening the Quality Management of Ready Mixed Concrete (JJF [2016] No.
14), entrusted a third party organization to carry out the second assessment of the quality of ready mixed concrete and the first assessment of the quality of prefabricated concrete components in 2022, The normal production of ready mixed concrete enterprises and prefabricated concrete component enterprises in the city were evaluated.
The specific information about the prefabricated concrete components is as follows: the evaluation of prefabricated concrete components has been carried out for 7 prefabricated concrete component manufacturers in our city, which are normally engaged in production.
The evaluation includes the quality management system, personnel and equipment, raw materials and accessories quality management, laboratory management, prefabricated component production management, data and delivery management, business capacity Design, R&D and informatization capabilities, sampling inspection of raw materials (concrete mixtures) and prefabricated components.
The average score of on-site evaluation was 91.93, and the sampling score rate was 90%.
（1） On site inspection The average score of the on-site evaluation in this evaluation is 91.93 points, including 6 enterprises with 90 points and above, 1 enterprise with 90 points to 80 points (inclusive), and no enterprise with less than 80 points (see Appendix 3 for the score of each enterprise’s on-site evaluation).
In this on-site assessment, 1463 three-level indicators were checked, 1056 of which were excellent, accounting for 72.18%; 217 items were evaluated as good, accounting for 14.83%; 82 items in the evaluation, accounting for 5.6%; 23 items were evaluated as poor, accounting for 1.57%; There are 5 non conformities assessed, accounting for 0.34%; 80 items were not involved, accounting for 5.47%.
(See Appendix 4 for the statistics of items with low scoring rate of the third level indicators) (II) The sampling and testing of raw materials, mixture test blocks and prefabricated components in this assessment includes 60 groups, including 46 groups of raw materials, 7 groups of mixture test blocks, and 7 groups of prefabricated components, with a scoring rate of 89.13%, 85.7%, and 100%.
（3） The main problems found in this assessment include: First, the confirmation procedures for the detailed design of the drawings of prefabricated components are incomplete, and the negotiation and change of the detailed design of the drawings are not timely; Second, the on-site identification of raw materials and components is not related to the quality information and inspection data of raw materials entering the site, so it is difficult to trace the source through the identification; Third, the video information of concealed acceptance of prefabricated components is incomplete and cannot fully and clearly reflect the site conditions; Fourth, the reinforcement welding, cushion block layout, formwork cleaning and component maintenance in the production of prefabricated components are not in place; Fifthly, some raw materials were found to be unqualified by spot check, among which the score rate of thermal insulation materials was relatively low.
Assessment and Grading of Fabricated Concrete Precast Component Enterprises in the First Half of the Year According to the on-site assessment and inspection of the quality of prefabricated concrete precast components and the spot check, the manufacturers of prefabricated concrete precast components participating in the assessment were graded.
There were 7 enterprises participating in the classification in the first half of the year.
According to the grading results, there were 4 enterprises classified as “low risk (excellent)” in the first half of the year, accounting for 57.14%; There are 3 “low risk (good)” enterprises, accounting for 42.86%.
On site evaluation scores of enterprises in the evaluation of prefabricated concrete precast units in the first half of 2022“.
