A novel and simple experimental apparatus has been assembled to allow model tests for free hanging steel catenary risers (SCRs). Tests can be conducted in both dry (air) and submerged (water) conditions. In this paper, main results from the experiments in air will be presented. Corresponding numerical model has been developed by software Orcaflex. Both experimental and numerical results are mainly consistent and demonstrate the influence of the in-plane motion of the platform on the dynamic response of the riser, as well as the influence of the soil models and forced motion frequencies on the dynamic response near the touchdown zone (TDZ).%为研究浮体运动、海床刚度对立管顶端张力和触地区动力响应的影响,开发了一套小比尺钢悬链线立管(Steel Catenary Riser, SCR)整体分析试验装置。以实际工作水深为900m 的一根 SCR 为研究对象,模型缩尺为1:435。用异步电机在水平、竖向和转动方向施加位移,幅值为50mm;模型管材料为硅胶,其顶端自由悬挂在位移施加端,相当于铰接;在触地区选择不同刚度的湿泡沫、干泡沫和玻璃模拟海床。通过试验得到立管触地区的运动响应和顶端张力的时程曲线。与 Orcaflex 的计算结果进行比较,吻合得较好。结果表明:激励运动的方向对立管触地区的运动幅值和顶张力的影响不大,而运动频率与海床刚度对它们的影响较大。
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