by In the 21st century, with the rapid development of science and technology, applied science continues to lead society, and construction has undergone significant changes.
New materials, new technologies, and new processes are constantly being applied in practical construction, especially the extensive use of pumped concrete.
As industrial waste or industrial by-products (fly ash and slag powder) with cementitious properties, they gradually play a dominant role in the development and utilization of concrete mixtures.
Previously, concrete was mainly characterized by low plasticity or plasticity, and the sand ratio was mainly considered based on its filling effect.
The selected sand ratio was generally smaller.
Nowadays, the determination of sand ratio for highly mobile concrete is mainly based on the principles of fluidity and pumpability, which has increased significantly compared to before.
All of these have caused significant changes to the surface of concrete structures.
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