The loose and weak fly ash has been strengthened to dense condition by vibroflotation. The relative density and unit weight have been increas- ed to 0.65 and 9.5 kN/m~3 from 0.09 and 8 kN/m~3 respectively.

• 极松散的灰渣经过振冲加固变成紧密状态；灰渣的相对密度与干容重分别从0.；09和8kN/m~3提高到0