摘要
本文结合具体工程需要,系统研究了在22m厚淤泥质粘土中制作27m的深长水泥土桩技术。文中根据大量的现场试验资料,提出2次提升喷浆、3次搅拌、叶片中部出浆的成桩工艺。指出要使深长水泥土桩搅拌均匀,须采用3层6片的搅拌叶片和55kW、60r/min以上的调速电机,并根据需要,在跟踪检测时发现的桩身薄弱部位,适当减速,以增加搅拌次数和水泥含量。最后提出控制水泥土搅拌均匀性的定量计算公式—叶片搅拌次数和喷浆后水泥土每点搅土次数大于40的标准。
This paper studies the construction technique of deep mixing pile with a depth of 27m in 22m thick muddy clay in order to meet the requirements of a large building. On basis of many test results, the construction technique of 2 time jet grouting and 3 time agitation is adopted. The 6 blades in 3 heights and speed changing motor with 55kW and 60r / min should be used. When the depth of low cement - soil strength is found by standard penetration test and unconfined compression test in the course of construction, the hoisting velocity should be decreased, and by so doing in order to increase the agitation cycle and cement content. Finally, the formula of cement - soil agitation cycles of blades that determines the quantitative standard of agitation homogeneity is put forward, and the agitation cycles should be more than 40 after each jet grouting.