山区风电锥体基础的倾覆稳定性分析

Stability Analysis on Overturning Resistance of Cone-Shaped Foundations for Mountain Wind Turbines

城郊山区风电可避免平原风电设施占据大量耕地及戈壁地区风电配套大量高压输电线路、成本较高等问题,城郊山区风电建设已成为满足城市用电的有效途径。锥体基础是一种新型的山区风机基础形式,与传统山区风机基础相比,能节约钢筋和混凝土用量,减少基坑开挖量及土方对环境的破坏,提高基础承载力。结合数值模拟和理论方法,对锥体基础基底的脱空面积计算方法、脱空百分比以及风化岩力学参量、基础几何尺寸对基底反力、基础水平位移和倾斜率的影响规律进行探讨;分析基础侧壁设置的橡胶层对卸载后基础回弹率的影响,并建立了锥体基础倾覆稳定性评价标准。

As wind turbines in mountain areas in outskirts of towns can avoid occupy a large amount of cultivated land for wind turbines on the plains and save a large number of high voltage transmission lines for wind turbines in the deserts,wind turbines in mountain areas in outskirts of towns have become effective ways to meet the electricity demand in urban energy-consumption.The cone-shaped foundation was an innovative type of the mountain wind turbine foundation,which outperformed the traditional wind turbine foundations in mountain areas in decreasing the usage of steel and concrete,in increasing the bearing capacity of foundations,and in reducing the excavation volumes of foundation and the bad effect of backfills on the environment.The calculation method of void areas between bottom surfaces of foundations and the rock masses was proposed.Combining numerical simulations with theoretical methods,the calculatioin method of void areas under bases was studied,and the influences of void ratios,mechanical indexes of weathered rock and geometric sizes of foundations on subgrade reaction,lateral displacement and the tilt rates of foundations were also disccused,respectively.Moreover,the effect of the rubber layer placed the sidewall of foundations on the rebound rates of unloaded foundations was analyzed.The stability of overturning resistance for the cone-shaped foundation was also constructed.