China is among the countries where earthquakes take place most frequently in the world. 60 percent of the areas have high earthquake intensity, and sand liquefaction is the main reason that causes seismic disasters. The evaluation of sand liquefaction is the most important content of engineering reconnaissance and the aseismatic design. So evaluating the sand liquefaction objectively and exactly is the precondition of taking preventive measures on areas where liquefaction easily occurs. It also ...