Design optimization and mechanics study of mixture ratio of super high toughness concrete.

Taking the closest packing as the starting point, adopting the "minimum water demand method" and the "closest packing model concept of aggregate" to design a super high toughness concrete mix ratio with polypropylene fiber, and through the workability and mechanical properties of the concrete, the proportion of the cementitious material, the type and proportion of the quartz sand, and the water-to-binder ratio in the mix ratio were adjusted and optimized. The test results showed that when the ratio of cement, mineral powder and silica fume was 70:15:15, quartz sand of 20-40 mesh and 40-120 mesh was 2.06:1,the water-to-binder ratio was 0.20, the dosage of steel fiber was 2% of the volume of concrete and the polypropylene fiber was 0.1% of the volume of concrete, the workability and mechanical properties of concrete were the best, and the 28 days flexural strength and compressive strength was up to 35MPa and 130MPa respectively, and the extension could reach 600 mm, which could meet the actual engineering demand. [ABSTRACT FROM AUTHOR]