However, what specific technical indicators does this special mechanism sand have? We introduce them in detail as follows.
The particle size gradation (accumulated sieve percentage) of machine sand should meet the requirement of cumulative sieve percentage of machine sand.
2. Alkali activity
It is preferred to use machine sand that does not contain alkali activity, that is, the expansion rate of the mortar rod is less than 0.10%. It is not allowed to use machine sand that has an expansion ratio of 0.30% or more or that contains alkali-carbonate reaction activity. When the mortar rod expansion rate is greater than or equal to 0.10% and less than 0.20%, the alkali content of the concrete should be calculated; when the mortar rod expansion rate is greater than or equal to 0.20% and less than 0.30%, in addition to the alkali content of the concrete, the addition of minerals should be adopted. The technical measures to suppress the alkali-aggregate reaction, such as whip, have been tested to show that the suppression is effective.
The requirements for artificial machined sand for railways are relatively high. If such high-quality machined sand is to be obtained, high-standard mechanical equipment is required to produce it. Traditional sand making machines have been difficult to meet production requirements. With the rapid development of society in recent years, new sand making machines suitable for various industries have been launched one after another, and have been respected by the market, thereby accelerating the modernization of society.