The main difficulty in soft-rigid composite pile technology is the selection of materials. According to relevant public information, the top part of the flexible-rigid composite pile is made of reinforced concrete, while the pile body is made of soft soil. This requires a good concrete-soft soil interface treatment to ensure the long-term durability of the pile. Stability, taking into account the stability of the pile body, different types of concrete need to be used to match the soft soil. This requires technicians to have the ability to accurately calculate the concrete mix ratio to meet different stability needs.