The performance indicators of the mandatory projects meet the requirements.
The performance indicators meet relevant requirements.
In this experiment, a concrete reference mix proportion with a strength grade of C30 was used (Table 1), and the workability and strength of the concrete were studied by adjusting the sand ratio and coarse aggregate particle size while maintaining the same water consumption, cementitious material dosage, and additive formula and dosage, To optimize the selection of raw materials and mix design for double-sided composite shear wall concrete.
It is necessary to select reasonable raw materials and conduct multiple experiments to optimize the mix ratio to improve construction performance and meet quality requirements.
The main body of the mother liquor is composed of a regulating type water reducing mother liquor, an air entraining agent, and a defoamer.
2 Mix proportion and test results 2.1 Concrete mix proportion Pre mixed concrete has a significant impact on the production efficiency and quality of double-sided composite shear walls.
By compounding the functional admixture rheological agent HJ, the workability and vibration resistance of the concrete are ensured.
Natural sand shall be tested in accordance with JGJ52-2006 “Standard for Quality and Inspection Methods of Sand and Stone for Ordinary Concrete”, and the results shall meet the requirements of Zone II medium sand standard for concrete with strength grades of C30~C55.
In recent years, as a new type of prefabricated component, the double-sided composite shear wall has also been partially applied.
1.
(2) Fine aggregate shall be selected from high-quality natural sand or ball milled water washed machine sand, with a specification of Zone II medium sand.
However, its single blade thickness is thin (usually only 50-70 mm), the spacing between steel bars is small, and the overall thickness of the wall structure and the protective layer of steel bars are strictly required.
Moreover, concrete must have high fluidity, low bleeding rate, etc.
(3) The coarse aggregate is selected from continuously graded ores, and the various indicators of each specification of coarse aggregate have very small differences, and all comply with the requirements of JGJ52-2006 “Standard for Quality and Inspection Methods of Sand and Stone for Ordinary Concrete”.
(5) The admixture is a polycarboxylic acid high-performance water reducing agent with good applicability to cement.
(4) The mineral admixture shall be Class F Grade I fly ash in accordance with GB/T1596 “Fly Ash for Cement and Concrete”, and its surface shall be free of black oil and obvious impurities after immersion.
Table 1 C30 Concrete Reference Mix Ratio kg/m3 Note: The water cement ratio is 0.44, and the sand ratio is 45%
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The raw material selection is (1) P ยท O42.5 ordinary Portland cement produced by Jidong Cement Company, and its various performance indicators are tested in accordance with GB/T1346-2011 “Testing Methods for Cement Standard Consistency, Water Consumption, Setting Time, and Stability” and GB/T17671-1999 “Testing Methods for Cement Mortar Strength (ISO Method)”, and the results meet the requirements.