18��סլ¥������Ȼ�ػ��еĺ�����������, �ػ�������巨����ͨ���Ը�¥��ͬ��λ�����غ����������ʩ���еij����۲�ó�: �Ϻ�������ϵĸ߲㽨���ػ�������巨�������ȡ�þ��ÿɿ���Ч��; �Ӵ���������ʿ�ʹ��������Ч�����Լ�С; ���׮���ϵػ��и���Ӧ����ɢ�������������ϲ����Ӳ��ǿ�����Ӷ�����, �����ϲ�������Ӱ��Ϊ��; ���ڷ������, �غ��������߳��������Ӱ�첻����ʵ��ӳ���ϵػ���ѹ���ԡ�

A residential buildings with 18 story built on the ground consisting of softmarine clay and the sub-grade was treated with vibroflotation. The load tests on different sites and layers and the settlement observations in main struction construction indicate that treat the softmarine clay with vibroflotation is economical and reliable for higher buildings; enlarge the power of vibration can diminish the effect of foundational settlement distinctly; the external stress in composite subgrade diffuses more rapidly with the increase of intensity in the hard layer which above the soft layer, but the main influence of the diffusion is in the thickness of this layer; the initial linear part of the load tests’curves do not truely express the compression of the composite subgrade for the raft foundation due to the effect of deepness.