摘要
河床或海床中会布设光缆、管线、隧洞等结构物,如果该水域上有船只抛锚,就要考虑抛锚对结构物安全的影响。通过模型试验探究了霍尔锚在黏土中的抛锚深度,研究了贯入速度、锚重以及土强度对抛锚深度的影响。在模型试验中,用MEMS加速度传感器捕捉锚在土中运动时的加速度,并由加速度积分得到锚的下落速度及对应的下落位移。模型试验结果表明:当霍尔锚以极限速度贯入软黏土中时,17.8 t锚在强度为7.5 k Pa土中的贯入深度为4.0 m; 42 t锚在强度为8.3 k Pa的土中贯入深度为6.7 m。根据试验结果建立了霍尔锚在土中动力贯入时的运动微分方程,分析了作用在锚上的各项受力,并预测了抛锚深度。此外,根据模型试验结果,建立了抛锚深度和锚的总能量之间的经验公式。
There exist optical cables,pipelines and tunnels within/on the riverbed or seabed.Hence these subwater or subsea systems are potentially to be affected by the drop anchor from ships above the water.Model tests are carried out to investigate the penetration depth of the hall anchor in the clayey soils.The factors,including the anchor impact velocity,the anchor weight and the soil undrained shear strength,that influence the anchor final penetration depth are investigated.In the model tests,a MEMS accelerometer was used to record the anchor acceleration during the anchor dynamic penetration in the soil.By integrating the anchor acceleration,the anchor velocity and the anchor displacement were derived.The testing results indicate that with the terminal velocity,the anchors of 17.8 t and 42 t can achieve final penetration depths of 4.0 m and 6.7 m in soils with undrained shear strengths of 7.5 kPa and 8.3 kPa,respectively.Based on the model testing results,a theoretical analysis based on the Newton’s Second Law was made on the forces on the hall anchor so as to predict the anchor final penetration depth.Finally,an empirical equation was put forward to predict the anchor penetration depth based on the anchor total energy.
作者
韩聪聪
陈学俭
刘君
HAN Congcong;CHEN Xuejian;LIU Jun(State Key Laboratory of Coastal and Offshore Engineering,Dalian University of Technology,Dalian 116023,China)
出处
《海洋工程》
CSCD
北大核心
2018年第5期90-98,共9页
The Ocean Engineering
基金
国家自然科学基金项目(51539008
51479027)
关键词
霍尔锚
抛锚深度
黏土
抛锚速度
hall anchor
anchor penetration depth
clayey soil
impact velocity
