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本文报道了上海地区由粘土和粉砂组成的不均匀地基中的打入桩和压入桩的研究工作。讨论了穿过上复砂质粉土进入粉砂层的单桩承载力，以及穿过粉砂层进入下卧软粘土的桩的情况。通过桩身轴力量测，发现粉砂层的极限端阻力σｕ及极限侧摩阻力平均值随进入粉砂层的深度呈线性增加，获得了σｕ及各自的临界深度的参考值；当桩端接近粉砂一粘土分界面时，桩可能会因冲穿粉砂层进入下卧粘土层而发生破坏，获得了σｕ及的临界厚度的参考值。由于粉砂层的剪缩性，使得同一桩端处的打入桩与用千斤顶逐步贯人的桩的承载力Ｐｕ、σｕ及值均有较大的差别。
This paper reports on the study of driving piles into piles and press-fitting piles in uneven ground composed of clay and silt in Shanghai. The bearing capacity of single piles passing through the upper sand sandy silt into the silty sand layer and the situation of passing through the silt layer into the piles of the soft clay underneath are discussed. Through the shaft shaft force measurement, it was found that the average value of the ultimate resistance σu and the limit side frictional resistance of the silt layer increases linearly with the depth of the entry silt layer, and the σu and their respective critical depth reference values are obtained; when the pile end approaches When the silt-clay interface is established, the pile may be damaged by punching through the silt layer into the underlying clay layer, and a reference value for the critical thickness of σu is obtained. Due to the shear properties of the silty sand layer, the bearing capacity Pu and σu and the value of the pile driven at the same pile end and the pile used to gradually penetrate the pile have great differences.