Foundation Soil Response to Wind Turbine Generator Loading

风力涡轮机发电机（WTG）结构通常支撑在大的八边形（在基部处）混凝土和钢筋增强体上，该混凝土和钢筋增强体支撑倾覆、旋转刚度和承载能力稳定性要求。 系统的倾覆稳定性和最大承载压力随风速和风向而变化。 高偏心载荷条件（即，倾覆力矩与垂直重力载荷的比值较大）导致不均匀的压力分布，该压力分布被假定为在椭圆形有效区域上的均匀土压力分布，该椭圆形有效区域由于系统偏心距而偏离基础中心。然而，这种假设的分布在机械上是不正确的。 目前的风力发电机基础理论依赖于弹性半空间模型，已开发用于其他目的，几乎没有物理证据来支持该模型在风力发电机基础系统。 因此，动态剪切模量值和压力分布假设的现场验证与建立机械上正确的WTG基础响应以及动态应力-应变关系与深度相关性沿着非常相关（与刚度和沉降分析相关）。威斯康星大学麦迪逊分校与哈特兰社区学院合作，（Illinois）对即将投入使用的风力发电机基础进行仪器化，重点是评估动态力和基础土壤对运行中风力作用的响应。 监测将测量动态力参数（幅度和周期），监测地基土响应，并分析和制定机械验证的动态地基响应建议。 拟议的研究计划的结果将通过推广和教学活动在多个教育环境中利用。 该项目将提供一个机会，让本科生和研究生参与可再生能源系统的建设，分析和运营。实验结果和分析将纳入PI？美国国家认可和参加继续工程教育短期课程的风能，包括风涡轮机基础和塔系统设计和风能民用平衡的工厂设计。 此外，结果将直接用于PI的第一个同类，在工程的UW-Madison学院的学分设计课程-CEE 639，风能现场设计和施工。

A wind turbine generator (WTG) structure is typically supported on a large octagonal (at the base) mass of concrete and steel rebar reinforcement that supports overturning, rotational stiffness, and bearing capacity stability requirements. The overturning stability and maximum bearing pressure of the system vary as a function of wind speed and direction. The highly eccentric loading conditions (i.e., large ratio of overturning moments to vertical gravity loads) lead to an uneven pressure distribution that is assumed as a uniform soil pressure distribution over an oval-shaped effective area offset from the center of the foundation by the system eccentricity. However, this assumed distribution is mechanically incorrect. Current WTG foundation theory relies on elastic halfspace models that have been developed for other purposes, with little physical evidence to support the model in a WTG foundation system. Because of this, field verification of dynamic shear modulus values and pressure distribution assumptions is very relevant to establishing mechanistically correct WTG foundation responses, along with dynamic stress-strain relationships versus depth correlations (relevant for stiffness and settlement analyses).The University of Wisconsin-Madison is working with Heartland Community College (Illinois) on instrumenting a WTG foundation that will shortly be put into service, with emphasis on evaluating the dynamic forces and the foundation soil response to in-service wind action. The monitoring will measure dynamic force parameters (magnitudes and periods), monitor foundation soil responses, and analyze and develop recommendations for a mechanically validated, dynamic foundation response. The results of the proposed research program will be leveraged across multiple educational environments through outreach and teaching activities. The project will provide an opportunity to engage undergraduate and graduate students with the construction, analysis, and operation of a renewable energy system. Experimental results and analyses will be incorporated into the PI?s nationally recognized and attended continuing engineering education short courses in wind energy including Wind Turbine Foundation and Tower System Design and Wind Energy Civil Balance-of-Plant Design. In addition, results will be directly used in the PI's first of its kind, for-credit design course in the UW-Madison College of Engineering - CEE639, Wind Energy Site Design and Construction.