Machine-made sand refers to sand processed by sand making machine and other auxiliary equipment. The finished product is relatively regular, and can be processed into sand with different rules and sizes according to different technological requirements, which can better meet daily needs. Machine-made sand needs professional equipment to produce qualified and applicable sand and gravel.
Sand making characteristics:
Robustness and durability test. The firmness of machine-made sand is slightly worse than that of river sand, but it still reaches the standard of GB/T 14 1684293, and it is no problem to use it in ordinary concrete. However, when it is used in concrete members that are often subjected to friction impact, in addition to additives, it is necessary to control the cement-sand ratio of concrete, the crushing index of sand and the content of stone powder.
Influence of the content of machine-made sand and gravel powder on the properties of cement mixture. Through cement test, mortar test and concrete test, there is no big difference between the concrete prepared with machine-made sand and natural sand. Generally speaking, under the premise of the same slump, the water consumption of machine-made sand is slightly larger, but it should be considered comprehensively according to the construction conditions, structure and transportation. But the strength of concrete is basically unchanged; When preparing pumping concrete and other special concrete with machine-made sand, pay attention to the fact that the sand ratio should not be too high, so as to avoid reducing the engineering quality of concrete strength and durability.