Soil Structure Interaction Analysis for Energy Foundations

能源需求的增加、化石燃料储量的减少以及对碳排放导致气候变化的有害影响的日益关注，使得有必要寻找替代的、可再生的和清洁的能源。风能和地热能是清洁和可再生能源，可以通过建立海上风力发电场和建造结构基础来经济地提取，这些结构基础具有从地下提取地热能和为建筑物和结构提供机械支持的双重目的。最近在欧洲和世界其他地区安装的海上风力涡轮机（OWTs）使总发电能力超过11027兆瓦。风力发电厂大多建立在单桩基础上，可以沿着加拿大漫长的海岸线提供持续稳定的风能供应。单桩设计需要改进，特别是针对循环负荷，以提高风电场的成本效益和可靠性。据估计，在住宅和商业建筑中使用地热能可以减少45-80%的二氧化碳排放，节省18-56%的成本。在加拿大，通过能源桩基础提取地热能是非常可行的，因为地表以下几英尺的温度在20°-35°C的狭窄范围内保持稳定。能源桩的主要问题是缺乏精确的设计方法，因此能源桩的可靠性在加拿大的打桩行业还没有很好地建立起来。提出的研究将通过(1)开发支撑海上风力涡轮机单桩的海洋沉积物的本构模型，(2)开发分析和数值框架来研究单桩在循环荷载下的长期性能，(3)将分析扩展到考虑土壤性质随机空间异质性的概率框架，解决目前单桩基础和地热桩基础设计中的空白。(4)对风力发电单桩进行地震分析；(5)利用地热能源桩应用的实验室试验研究土壤和土-混凝土界面的热-力学行为；(6)开发土壤的热塑性、非等温土本构模型；(7)开发分析能源桩在机械和热载荷下的数值框架；(8)在研究的基础上改进风力发电单桩和地热桩的设计方法。(9)风电单桩和地热能桩的可持续性评价。提出的研究计划将为单桩和能源桩的分析和设计建立一个开创性的、合理的框架。由于专业人士将认识到研究的价值，该框架将在实践中得到采用，这将有助于加拿大民用基础设施与清洁能源技术的可持续发展。

Increasing energy demands, dwindling fossil fuel reserves and a heightened concern for the detrimental effects of carbon emissions leading to climate change have made it necessary to search for alternate, renewable and clean energy sources. Wind and geothermal energies are clean and renewable energies that can be extracted economically by setting up offshore wind farms and by constructing structural foundations which serve the dual purpose of extracting geothermal energy from the ground and providing mechanical support to buildings and structures. Recent installations of offshore wind turbines (OWTs) in Europe and other parts of the world have led to a total power generation capacity of over 11,027 MW. OWTs are mostly founded on monopile foundations and can provide a continuous and steady supply of wind energy along the long coast lines of Canada. Monopile design requires improvement, particularly against cyclic loads, to improve the cost-effectiveness and reliability of the wind farms. It is estimated that the use of geothermal energy in residential and commercial buildings may lead to 45-80% reduction in CO2 emissions and to 18-56% cost savings. The extraction of geothermal energy through energy pile foundations is very viable in Canada, because the temperature at a few feet below the earth's surface remains stable within a narrow range of 20°-35°C. The main concern in using energy piles is the lack of a precise design method because of which the reliability of energy piles is not well established in the Canadian piling industry. The proposed research will address the current gaps in the design of monopile foundations and geothermal pile foundations by (1) developing constitutive models for marine deposits supporting offshore wind-turbine monopiles, (2) developing analytical and numerical frameworks to investigate the long-term performance of monopiles under cyclic loads, (3) extending the analysis to a probabilistic framework considering the random spatial heterogeneity of soil properties, (4) performing earthquake analysis of the wind-turbine monopiles, (5) investigating the thermo-mechanical behavior of soil and soil-concrete interface using laboratory tests for geothermal energy pile applications, (6) developing thermoplastic, non-isothermal soil constitutive models for soil, (7) developing a numerical framework to analyze energy piles under mechanical and thermal loads, (8) improving design methodologies of wind-turbine monopiles and geothermal piles based on the research, and (9) performing sustainability assessment of wind-turbine monopiles and geothermal energy piles. The proposed research program will establish a pioneering, rational framework for the analysis and design of monopiles and energy piles. As the profession will recognize the value of the research, the framework will be adopted in practice, which will contribute to the sustainable development of civil infrastructure in Canada with clean energy technologies.