Composite binders for concretes with improved shock resistance

Building Materials

The qualitative and quantitative composition and properties of the initial materials, composite binders and concrete samples were studied. Optimal compositions of concrete for protective structures that provide the maximum static and dynamic strength characteristics are selected. In this case, the effect of increasing the shock endurance increases to 6 times. It has been found that concretes with a small number of defects, high packing density and uniformity, good adhesion between the aggregate and cement stone, an increased ratio of static tensile strength to static compressive strength Rtens / Rcompr and ductility have the best resistance to dynamic impact. It is proved that this ratio can be increased, in the case of the use of dispersed reinforcement of concrete (so-called fibrous concrete). In experimental studies on penetration of both unreinforced and fiber-reinforced concrete slabs, it was noted that samples of unreinforced concrete were completely destroyed in large and small pieces, while samples of fiber-reinforced concrete were not completely destroyed, and only through penetration at the impact site was observed; that is, fibrous concrete has the best impact resistance. These results can be applied to the design of various special structures, such as protective structures of civil defense and emergency situations, concrete structures of nuclear power plants, etc.