In fact, the sand and gravel aggregates used in our country in the past were basically natural sand and gravel collected directly from rivers and mines. Years of mining have put the resources at risk of depletion. As my country's ecological civilization construction continues to advance, resource and environmental constraints and controls have become increasingly strengthened, making the contradiction between supply and demand more prominent. Sand and gravel prices have also continued to rise, with sand and gravel prices rising by nearly 100% in some areas. As a last resort, coastal areas such as Guangdong, Fujian, Zhejiang, Jiangsu, and Hainan have begun to import large quantities of sand and gravel from countries such as Malaysia and North Korea.