摘要
从柔性桩有效桩长的沉降出发,通过弹性理论和Mindlin位移解分别推导出桩顶和桩间土顶的沉降量计算公式。根据在刚性基础下桩土顶面的位移协调条件,推导搅拌桩有效桩长的计算方法,利用室内试验结果对推导所得的公式进行简化,从而得到便于工程应用的复合地基有效桩长的计算方法。数值计算结果表明,桩身弹性模量(Ep),桩间土弹性模量(Es)和泊松比μ的取值对有效桩长的计算结果有明显的影响。在实际设计中的Ep,Es和μ的取值应该根据现场试验结果来确定,使计算结果能更好地与实际结果相符。此外,将推导所得计算公式与现有的一些计算方法进行比较分析,结果表明,当Ep/Es为50左右时,有效桩长的计算偏差约为5％。现场试验结果表明柔性桩复合地基的Ep/Es值一般也为50左右,因此,可以认为推导出的有效桩长的计算方法具有实用价值。
Based on the concept of effective length of flexible pile, the displacements for top of pile and surface of soil between piles were formulated by elastic theory and Mindlin displacement solution. Considering the displacement compatibility equations with stiff foundation, a method was proposed to calculate the effective length of flexible pile for composite foundation. And a simplified calculation method was proposed after using some experimental results, which can be easily and conveniently used for practical project of composite foundation. Numerical calculation results show that parameters, the elastic ratio of pile（Ep）, elastic ratio of soil（Ex） and poisson ratio（μ） have an evident effect on the effective length of flexible pile, so the result will be more useful to explain the problems of the flexible pile for composite foundation if Ep, Es and μ are decided by test in-situ. Moreover, comparing the calculation results herein and those by other methods, there is only about 5% error of effective length when Ep/Es is about 50%. Results of test in-situ also identify that about 50% for ratio of Ep to Es is common for flexible pile. So the present method for calculating effective length of flexible piles is useful and practical.
出处
《中南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2007年第1期175-179,共5页
Journal of Central South University:Science and Technology
关键词
有效桩长
MINDLIN位移解
搅拌桩
复合地基
effective pile length
Mindlin displacement solution
mixing cement piles
composite foundation
