What is the meaning of SMW method for foundation pit support? What are its advantages and disadvantages?

H-shaped rigid or other tensile materials are inserted into concrete mixing piles to form a composite structure with dual functions of stress and seepage prevention, that is, rigid concrete mixing method. Japan calls smw construction method! Its advantages are low construction noise, little environmental impact, good water sealing effect and high physical strength. Disadvantages are: lack of application experience, difficult recovery of H-beam and high cost.