吸力贯入式板锚转动上拔过程的数值模拟研究

吸力贯入式板锚(SEPLA)是一种系泊深海浮式结构的新型基础,在转动上拔的过程中其埋深和承载力会不断减小。采用包络面塑性极限分析方法,对吸力贯入式板锚在其转动上拔的过程中的埋深损失和承载力进行了模拟分析,并考虑锚链、土和板锚的相互作用。研究了切向偏心、锚链泥线夹角等参数对埋深损失、板锚转角、承载力的影响,并与离心机模型试验数据验证。研究结果表明,随着锚眼切向偏心的增大,板锚埋深损失逐渐减小,甚至出现埋深增大的现象,但相应的承载力显著降低。当偏心比ep/en0.1时,板锚的承载力基本不变;当ep/en0.1后,板锚的承载力随ep/en增大而减小。泥线处锚链倾角越小时,板锚的转动角度越小,获得的承载力效果越好。

Numerical study on keying of suction embedded plate anchors

The suction embedded plate anchor (SEPLA) is a new foundation to moor floating structures in deep water. Loss of embedment during keying has a significant effect on the design capacity. The envelope analysis method of plastic limit is adopted to simulate and analyze the embedment loss and the capacity of the keying process of SEPLAs, taking into account of the interactions of anchor chain, soil and plate anchor. The effects of varying padeye offsets and mudline angle of anchor chain on the embedment loss, inclination and capacity of the plate anchor are studied, and they are verified by the data of centrifuge experiments. The results from simulations show that the embedment loss of SEPLA decreases with the increase of padeye location offset towards the bottom of the anchor. The capacity of the plate anchor keeps stable when the eccentricity ratio of e_p/e_n is less than 0.1. When e_p/e_n is greater than 0.1, the bearing capacity of plate anchor significantly decreases. Besides, a better result of the bearing capacity can be yielded under the condition of a smaller mudline angle of the anchor chain with a smaller rotation angle.