由于宽浅式筒型基础具有不同于传统筒型基础的超大直径（D≥30 m）和较浅入土深度（d≤15 m）,因此其竖向承载模式和极限承载力计算方法有待研究。通过数值分析得到宽浅式筒型基础在达到竖向极限承载力时的破坏模式,引入承载力极限分析理论,构建宽浅式筒型基础竖向极限承载的地基破坏机动场;结合虚功方程采用Matlab求解宽浅式筒型基础竖向极限承载力的上限解,计算结果与数值分析结果和离心试验结果吻合良好。
Abstract
The wide and shallow bucket foundation, as a new type of the offshore wind power foundation, is suitable for the soil with many soft clays. And this type of foundation has the characteristic of shore prefabrication, overall floating transportation and overall installation resulting in a good benefit of economy. The calculation of vertical bearing capacity is the basis to realize the composite bearing characteristics of the foundation for offshore wind turbine. Due to the large diameter （D≥30 m） and relatively shallow penetration depth （d≤15 m） compared with the traditional bucket foundation, the vertical failure mechanism and the calculation method of bearing capacity of the new type foundation still need to be studied. The corresponding failure mechanisms are established based on the results of numerical analysis. The upper bound solution limit analysis for vertical bearing capacity was established combined with the virtual work equation, the upper bound solution limit analysis for vertical bearing capacity of bucket foundation is established by using the Matlab mathematical software. And the results of the upper bound solution limit analysis have a good agreement with the calculation of the numerical analysis and the centrifuge test.
关键词
海上风电机组 /
极限承载力 /
数值分析 /
筒型基础 /
极限分析上限解
Key words
offshore wind turbines /
bearing capacity /
numerical analysis /
bucket foundation /
upper bound solution limit analysis
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