砂土中多锚片螺旋锚上拔承载力计算方法研究  

Research on calculation method of uplift bearing capacity of screw anchor with multi-blades in sandy soil

作　　者：李逸奇 胡伟[1,2] 杨枭 黄勇祥 LI Yiqi;HU Wei;YANG Xiao;HUANG Yongxiang(Hunan Province Key Laboratory of Geotechnical Engineering Stability Control and Health Monitoring,Hunan University of Science and Technology,Xiangtan 411201,China;School of Civil Engineering,Hunan University of Science and Technology,Xiangtan 411201,China;CCCC Guangzhou Water Transportation Engineering Design&Research Institute Co.,Ltd.,Guangzhou 510221,China;Hunan Electric Power Design Institute Co.,Ltd.,China Energy Group,Changsha 410007,China)

机构地区：[1]湖南科技大学岩土工程稳定控制与健康监测湖南省重点实验室,湖南湘潭411201 [2]湖南科技大学土木工程学院,湖南湘潭411201 [3]中交广州水运工程设计研究院有限公司,广东广州510221 [4]中国能源建设集团湖南省电力设计院有限公司,湖南长沙410007

出　　处：《海洋工程》2024年第4期188-196,共9页The Ocean Engineering

基　　金：国家自然科学基金资助项目(52178332)。

摘　　要：对于砂土中多锚片螺旋锚上拔承载机理和承载力学模型的研究,目前存在人为引入临界值将连续演化问题分割为特殊工况,但临界值取值标准又难以形成统一认识的问题。基于数值模拟分析了砂土中螺旋锚锚周土体滑动面的连续演化规律和理论表征方法,并进一步研究砂土中多锚片螺旋锚上拔力学模型和上拔承载力计算方法。所得主要结论为:1)多锚片螺旋锚上层锚的承载性状仅与其埋深比有关,与单锚表现一致;2)随着间距比的增大,下层锚承载性状受间距比的影响逐渐减小,直至独立承载;3)各层锚片锚周土体滑动面均可用椭圆的部分圆弧刻画,间距比很小时,椭圆的长短轴比取决于间距比而与埋深比无关,其余情况下椭圆的长短轴比均随埋深比的增大而减小;4)多锚片螺旋锚的上拔承载力学模型可通过各层锚的承载模型组合而成,下层锚力学模型的演化受埋深比和间距比的影响可分为3个连续阶段;5)与3个试验案例的对比计算证明了连续演化+组合式力学模型构建思路的合理性,相应的承载力计算方法也具有较好的精度和稳定性。There is a problem of research on the mechanism of uplift bearing and mechanical model of screw anchor with multi-blades in sandy soil.Currently,it is difficult to form a unified understanding of the criteria for artificially introducing critical values to divide the continuous evolution problem into special cases.Based on numerical simulation,the continuous evolution law and theoretical characterization method of the sliding surface of the surrounding soil of screw anchors in sandy soil were analyzed,and further research was conducted on the mechanical model of uplift and the calculation method of uplift bearing capacity of screw anchor with multiblades in sandy soil.The main conclusions obtained are as follows:1)The bearing characteristics of the head blade only related to their burial depth ratio,which is consistent with the performance of the single anchor blade.2)As the spacing ratio increases,the bearing characteristics of lower anchor blade gradually decrease with the influence of the spacing ratio,until independent bearing;3)The sliding surface of the surrounding soil of each layer of anchor blades can be described by partial ellipses,and when the spacing ratio is small,the ratio of the long and short axes of the ellipse depends on the spacing ratio and is independent of the burial depth ratio;in other cases,the ratio of the long and short axes of the ellipse decreases with the increase of the burial depth ratio;4)The uplift bearing mechanical model of screw anchor with multi-blades can be composed of the bearing models of each layer blade,and the evolution of the mechanical model of lower-layer blade is divided into three continuous stages influenced by the burial depth ratio and spacing ratio;5)Comparison calculations with three experimental cases prove the rationality of the continuous evolution+combination mechanical model construction approach,and the corresponding bearing capacity calculation method also has good accuracy and stability.

关 键 词：多锚片螺旋锚 埋深比 间距比 滑动面 力学模型 上拔承载力 

分 类 号：P753[交通运输工程—港口、海岸及近海工程] TU473[天文地球—海洋科学]