Can desert sand replace river sand for concrete?

In the eyes of people who do not know the inside information, there may be such a question, there are a large number of deserts on the earth, if these sands are used, will there be no shortage of river sand? I believe many people will think so. In fact, deserts often have the problem of salinization, if the sand with high alkali content is used for construction, after becoming concrete, it will quickly interact with external active ingredients, concrete will absorb water and expand, thereby reducing the hardness and cohesion of cement, and is also prone to safety problems, in addition to sand composition, desert sand because of the perennial wind cutting, handling, does not have the granularity required by construction projects, nor can it meet the building requirements.

In order to ensure safe production, China can only import river sand. Southeast Asia, which is a good river sand import area in China, is still open to sand mining, and even welcomes someone to help them clean up the river, and the most important thing is to increase the national finance and the income of local residents. Malaysia has abundant rivers, rugged and windy rivers, and abundant precipitation, so after river washout, many mudflats form downstream. Moreover, the river sand particles it produces are uniform, the size is moderate, and impurities cannot be seen with the naked eye, which is a very good construction raw material. At present, Malaysia’s annual sand output can be hundreds of millions of tons, and the export volume is 23 million tons, which can fully meet the gap of construction sand in China.