减饱和法是近年来提出的一种可液化地基处理方法，其基本原理是通过工程措施减小饱和砂土地基中的饱和度，将饱和砂土地基变成不饱和砂土地基，从而提高地基的抗液化强度，减轻地震时产生的液化震害。该文利用井点降水法，在砂土地基中布置排水管，考虑排水管的竖向布置、水平布置、倾斜布置以及联合布置，对井点降水法的抗液化效果进行了振动台模型试验。实验结果表明：排水管水平布置产生的超孔隙水压最小，抗液化效果最好；竖直布置次之；倾斜布置抗液化效果最不明显。在实际应用过程中，可以定期进行地基土体的排水作业，从而提高可液化地基的抗液化能力。
The liquefaction resistance of saturated, sandy foundations can be improved by reducing the saturation. The well-point dewatering method was used to lower the saturation of the subsoil using vertical, horizontal, inclined and combined drainage pipes arrangements. The horizontal arrangement gave the best liquefaction resistance with the lowest induced excess pore pressure during the shaking. In engineering practice, the dewatering method can be used at regular intervals to reduce the liquefaction possibility.
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