摘要
对软土地区长抗拔桩中常用的常规直桩、扩底桩、注浆直桩的承载力性状进行了比较分析,研究了不同桩型的荷载传递规律和承载力提高机理,并引出其荷载-位移的理论计算公式,认为抗拔桩存在"有效桩长"。通过对某沿海城市不同超长抗拔桩的现场抗拔试验,分析比较了各种桩型在30mm上拔位移控制值下的单桩承载力和桩侧摩阻力分布规律,认为超过"有效桩长"的设计是不经济的,注浆直桩可以提高安全系数,宜优先选用注浆直桩。
The long uplift piles are researched in this paper through the comparative analysis of conventional straight piles, grouting piles and under-reamed piles. The theoretical equation of load-displacement is derived by a mathematical model. The mechanism of increasing load-carrying capacity and load transfer law of the different piles are studied by analysising the load-carrying capacity when the displacement of the pile top is 30 mm, and the distribution of frictional resistances of different style of piles in a mollisol area of coastal. The grouting straight piles should be the priority selection because of the increase of safety probability.
出处
《岩土工程技术》
2009年第6期284-287,共4页
Geotechnical Engineering Technique
关键词
抗拔桩
常规直桩
扩底桩
注浆直桩
“有效桩长”
uplift pile
conventional pile
enlarged base pile
post grouting pile
critical length of pile
