砂土中陆地风电空心锥形基础水平承载力的影响因素分析

空心锥形基础是一种新型的陆地风电基础形式,其主控荷载为水平荷载和倾覆力矩。开展砂土中锥形基础水平单调加载模型试验,研究加载高度、加载速率和模型尺寸对基础水平承载力的影响,并对比分析相同质量和径高比的锥形基础与圆形基础的水平承载力大小。研究表明:锥形基础水平极限承载力随加载高度增加逐渐降低;加载速率对锥形基础的水平极限承载力影响较小;径高比和底板尺寸是影响锥形基础水平极限承载力的主要因素,当基础径高比为5.5时,锥形基础水平承载力最大;增大底板尺寸可有效控制基础水平侧移;基础失稳破坏形式为转动破坏;相同质量的锥形基础和圆形基础相比,锥形基础的水平承载力是圆形基础的1.1～1.2倍。

Influence Factors of Horizontal Bearing Capacity of Hollow Cone-shaped Foundation for Onshore Wind Turbine in Sand

The cone-shaped foundation is a new type of foundation for mountain wind turbines. The horizontal load and the overturning moment predominate the foundation design. The horizontal monotonic loading model test of cone-shaped foundation in sand was carried out to study the effects of loading height, loading rate and model size on the horizontal bearing capacity of foundation. The horizontal bearing capacity of cone-shaped foundation and circular foundation with the same diameter-height ratio or same mass were compared and analyzed. The test results show that the horizontal ultimate bearing capacity of cone-shaped foundation decreases with the increase of loading height. The effect of loading rate on the horizontal ultimate bearing capacity of cone-shaped foundation is not obvious. Diameter-height ratio and floor size are the main factors that affect the horizontal ultimate bearing capacity of cone-shaped foundation, of which the cone-shaped foundation with diameter-height ratio of 5.5 has the largest horizontal bearing capacity. Increasing the floor size can effectively control the horizontal lateral displacement of foundation. When the foundation is unstable, the movement form is rotation. The horizontal bearing capacity of cone-shaped foundation is higher than that of circular foundation with the same mass.