通过对杭州地区淤泥质土、粘土和砂质粉七地层中现场取样的桩侧泥皮土和桩间土的室内物理力学参数对比试验,研究了泥皮土和桩间土在物理力学性状上的差异,分析了泥皮土对钻孔灌注桩桩侧摩阻力的影响。通过对掺入不同水泥浆含量的混合士的物理力学参数的试验研究,分析了水泥浆对改善桩侧泥皮土物理力学性状的作用效果。结果表明:泥皮土具有含水率高、孔隙比大、压缩件高、摩擦力低、抗剪强度低等特点,其工程性质明显比桩间土差,形成了桩土间的薄弱层,降低了桩侧摩阻力,注入水泥浆能有效的改善泥皮件状。
Through laboratory tests on mudcake and soil between bored piles in mud, clay and silt in Hangzhou, the influence of mudcake on shaft friction and the difference between mudcake and soil between bored piles were studied. In addition, by using laboratory tests on mud mixed with cement grout, the improved effect on mudcake with cement grout was analyzed. It was shown that compared with soil between bored piles, mudcake had high moisture content, high void ratio, high compressibility, low friction and shear strength. Mudcake was weaker than the pormer and became a weak layer between pile and soil and reduced the shaft friction of piles. Grouting could evidently improve mudcake.