Abstract:

The gravel drainage layer was set around underground structure. The numerical liquefaction experiment was separately completed  in the free field, the non-free-field and the gravel drainage layer non-free-field using FLAC3D.  The liquefaction distributed characteristic of the gravel drainage layer non-free-field was studied. The antiliquefaction effect of the gravel drainage layer was investigated, and the  dynamic characteristic change of underground structures after imposition of a gravel drainage layer in liquefaction field was analyzed. Calculations indicate that  the gravel drainage layer around the underground structure was not liquefied, the excess static pore pressure was obviously reduced in the distant liquefaction field, the structure did not float, and the horizontal drift was reduced. As the overall quality and rigidity of the structure with gravel drainage layer increased, the stability of the structure increased. Further research  will provide a theoretical and experimental basis for the design of underground structures through the liquefaction soil layer.

Key words:  non-free-field, excess static pore pressure ratio, gravel drainage layer, stability