The influence of the drainage regime on the installation and the response to vertical cyclic loading of suction caissons in dense sand
The influence of the drainage regime on the installation and the response to vertical cyclic loading of suction caissons in dense sand
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DOI：
10.1016/j.oceaneng.2020.107105
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发表时间：
2020-11
影响因子：
5
通讯作者：
Marc Stapelfeldt-;B. Bienen;Jürgen Grabe
中科院分区：
文献类型：
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作者：
Marc Stapelfeldt-;B. Bienen;Jürgen Grabe
海上风力涡轮机被认为是可再生能源的一个组成部分。密集的沙子通常是海床的特征，吸力沉箱基础越来越多地用于支撑北海站点的海上风力涡轮机。石油和天然气行业在这一技术方面有着丰富的经验，尽管这些平台通常位于以粘土为主的深水中。因此，需要进行研究以转移现有知识。本文讨论了一系列的离心试验，调查的安装和荷载传递机制，控制响应的吸力沉箱埋在密实的砂受到垂直循环荷载。通过在不同泵送流量下进行吸力式安装后的沉箱内的静力锥贯入试验，评估了吸力式安装过程中内部土塞可能松动对使用中基础性能的影响。在随附的测试中，研究了响应垂直循环载荷的载荷位移行为，包括张力的显着偏移。结果表明，孔隙流体行为是影响响应的关键因素，安装过程中施加的泵送流量影响较小。根据试验结果，本文提出了一种预测吸力式沉箱在竖向循环荷载作用下性能的简化方法。
Offshore wind turbines are considered as an integral part of renewable energy. Dense sand often characterises the sea bed and suction caisson foundations are increasingly used to support offshore wind turbines at North Sea sites. Significant experience with this technology exists in the oil and gas industry, although these platforms are typically located in deeper water with predominantly clay soils. Therefore, research is required to transfer the existing knowledge. This paper discusses a series of centrifuge tests that investigate the installation and the load transfer mechanisms governing the response of suction caissons embedded in dense sand subjected to vertical cyclic loading. The effect of potential loosening of the internal soil plug during suction installation on the in-service foundation performance is evaluated through cone penetration tests inside the caisson following suction installation at different pumping flow rates. In accompanying tests, the load displacement behaviour in response to vertical cyclic loading is investigated, including significant excursions into tension. The results identify the pore fluid behaviour as the key factor affecting the response, with the pumping flow rate applied during installation being less influential. Based on the findings from the experiments a simplified approach for the prediction of suction caisson behaviour under vertical cyclic loading is presented.