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1.
何飞  陈杰  蒋昌波  赵静 《海洋学报》2018,40(5):24-36
海草所形成的植物消波体系能有效防止岸线的侵蚀。利用Sánchez-González等的实验数据分析了波浪非线性对海草消波特性的影响。研究结果表明,相对水深和波陡对海草床的波能衰减系数影响依赖于海草淹没度。相对波高一定时,拖曳力系数随相对水深的增大而增大。对给定的相对水深,拖曳力系数随波陡的增大而减小。波浪非线性对于规则波和非规则波海草消波特性的影响并不一致。用无量纲参数(邱卡数、雷诺数、厄塞尔数)表达拖曳力系数的效果取决于拖曳力系数与无量纲参数的关系中是否充分考虑波浪非线性对拖曳力系数的影响。  相似文献   

2.
波群对垂直桩柱的作用力   总被引:1,自引:0,他引:1  
在波浪槽中进行了具有不同群因子和连长的随机波群对三种直径的桩柱作用力的实验研究,指出波浪峰力的比值不随波群的连长变化,而随波群因子的增加而增大。由于桩柱是一非线性系统,作用力的群团子大于波浪的群因子,其连长小于波浪的连长。波浪峰力的比值不仅随KC数的增加而增大,还随波群因子GF的增加而增大。  相似文献   

3.
透空式进海路是连接人工岛与陆岸的一种新型结构,其所受波浪力是工程设计中重点关注的问题。本文开展物理模型试验,通过改变水深、波高、桥面底高、桥面宽度等试验条件,研究透空式进海路波浪力的变化规律。试验测量透空式进海路上部结构的动水压强分布,分析得到结构的浮托力和水平波浪力。研究发现:透空式进海路上部结构波浪力的主要影响因素为桥面相对净空高度,在相对净空高度接近0时,桥面浮托力达到最大值。通过分析试验数据,并参照文献中的已有波浪力计算方法,建立透空式进海路上部结构浮托力和水平波浪力的计算公式,公式计算结果与试验结果符合较好,对透空式进海路工程设计具有重要指导意义。  相似文献   

4.
针对北戴河海滩侵蚀现状,通过物理模型试验及FLOW-3D数值模拟,获得在不同水位与波高条件下人工沙坝作用下的波浪消减与岸滩演变效果,旨在获取相对坝顶水深和波陡对波浪透射系数的影响以及不同水位情况下岸滩演变规律。研究结果表明:相对坝顶水深与波陡是影响波浪透射系数的关键因素,透射系数随相对坝顶水深的增大而增大,随波陡的增大而减小,水位越低,人工沙坝的养滩效果越好。  相似文献   

5.
近年来海洋极端天气频发,港珠澳大桥西人工岛地处外海,与其相连接的桥梁非通航跨的桥面高程较低,容易受到海浪侵袭,威胁到岛桥功能的正常发挥和结构自身安全。针对西人工岛桥结合部周围的复杂地形条件,采用OpenFOAM®开源程序,分别对S、SSW和SW三个方向的极端波浪进行了数值模拟。通过数值计算结果与物理模型试验测量值的比较验证了的模型的准确性。分析了不同方向入射波的波高和沿岛体斜坡爬高的变化规律。随着波浪入射角的增大,人工岛南侧斜坡的波浪爬高呈逐渐减小,但在岛体西端靠近桥梁的位置处,波浪爬高逐渐增大;同时也反映了越浪和桥面上水风险的大小。研究旨在为实际工程的管理和设计提供参考。  相似文献   

6.
通过正向与斜向波浪对半圆型防波堤(不开孔出水堤)的实验研究,给出了其水力特性及单位堤长所受的无因次水平波浪力、竖向波浪力和波浪浮托力随各主要影响因素的变化规律,特别指出了斜向波浪力可大于正向波浪力及水平波浪力中波谷作用大于波峰作用发生的条件。  相似文献   

7.
大型浮绳式围拦网养殖设施作为一种海上新型养殖装备,其抗风浪能力是首要解决的问题,因而围拦网设施网衣结构的受力分析就尤为重要。依据正弦波理论和莫里森方法理论分析了围拦网设施局部网衣结构在垂直方向上的受力情况,利用网面等效法和集中质量法对局部网衣结构进行了仿真模拟,并将数值模拟结果与理论分析结果进行了对比,结果显示两者基本一致,平均误差在19%以内,其中,局部网衣结构所受的垂直波浪力随着波浪波高的增大而增大,浮子所受的浮力和垂直波浪力始终是围拦网设施垂直方向受力的主要因素。依据计算的结果,构建了大型围拦网养殖设施,顺利完成了海上抗风浪测试,结果表明围拦网设施整体结构设计的合理性,对网衣结构垂直方向上的受力分析在围拦网设施贴底系统和系泊系统的设计中具有一定的参考价值。  相似文献   

8.
斜坡堤典型胸墙波浪力的影响因素   总被引:1,自引:1,他引:1  
李雪艳  付聪  范庆来  王岗 《海洋科学》2015,39(12):118-129
为探求斜坡堤典型胸墙迎浪面所受波浪力大小的影响因素,设计前仰式、深弧式、后仰式和直立式4种结构型式胸墙进行相关的物理模型试验。通过在典型胸墙迎浪面间隔布置压力测点,获取所受波浪压力,并将其进行积分求和,得到胸墙所受波浪力,进而讨论相对波高、相对波长、斜坡坡度和胸墙结构型式对波浪力的影响。结果表明,相对波高与相对波长对胸墙所受波浪力影响显著;波浪力随着相对波高的增大而增大,随着相对波长的增大呈现先增大、后减小、再增大的变化趋势;波浪力随着斜坡坡度的增大而减小。斜坡堤弧形胸墙所受波浪力明显大于直立式胸墙所受波浪力;在斜坡堤弧形胸墙中,前仰式胸墙受力较其余两种型式胸墙受力小。研究结果将加深波浪对斜坡堤胸墙作用力的理解,为后续工程设计提供理论指导。  相似文献   

9.
为研究导流板对波浪作用下海底管线的影响,在FLUENT中建立二维数值波浪水槽对不同导流板高度的海底管线附近波浪场进行数值模拟,并将计算结果与试验结果进行了比较,结果表明,计算结果与试验结果较为吻合。添加导流板后管线表面压力分布及波浪力均发生变化。水平波浪力最大值随着导流板高度的增大而增大,而垂直波浪力最大值则随之逐渐减小。  相似文献   

10.
由于开孔前墙和消浪室具有强扰动作用,所以开孔沉箱结构具有很好的消浪效果。本文通过日照港岚山港区码头开孔沉箱结构的物理模型试验,研究了沉箱不同开孔位置的消浪效果和水动力特征,分析了不同方案的反射系数和越浪量。结果表明:水位对反射系数的影响较大,开孔位置较高的方案,其消浪性能较好,且越浪量较小。选择反射系数和越浪量均较小的设计方案进行了水动力试验,结果表明:水平力最大时对应的浮托力约为最大浮托力的60%;浮托力最大时对应的水平力约为最大水平力的75%;波浪对开孔沉箱的作用主要集中于外壁迎浪侧,内部结构受到的波浪力很小;第二消浪室波浪力小于第一消浪室。  相似文献   

11.
利用水槽二维物理模型对规则波及不规则波作用下明基床上开孔沉箱所受到的波浪力进行了较为系统的试验研究。分析了开孔沉箱总垂直力峰值时刻对应的总水平力与相对基床高度、消浪室相对宽度、波陡、相对水深以及开孔率等影响因素之间的关系,给出了明基床上开孔沉箱总水平力比值(总垂直力峰值时刻对应的总水平力/总水平力峰值)与各影响因素之间的计算关系式。研究成果可供实际工程参考应用。  相似文献   

12.
通过水槽物理模型试验,对不规则波作用下明基床上开孔沉箱所受到的波浪力进行了较为系统的试验研究,分析讨论了开孔沉箱总水平力峰(谷)值时刻对应的总垂直力与基床相对高度、开孔率、波陡、相对水深、消浪室相对宽度等影响因素之间的关系,并与暗基床的研究成果做了对比讨论,给出了明基床上开孔沉箱总垂直力比值(总水平力极值时刻对应的总垂直力/总垂直力极值)与各影响因素之间的计算关系式,研究结果可为工程应用提供参考。  相似文献   

13.
Accurate estimation of wave uplift force is essential to the designs of reliable coastal and marine structures.We presents a series of laboratory work here on the impact of regular waves on horizontal panels,from which an empirical formula to estimate accurately the wave uplift force on panels is established.The laboratory measurements show that the wave uplift force depends mainly on the incident wave height,the wave period,the wave length,the panel width,and the clearance between the subsurface of the panel and the still water level.Among these factors,the impact of the panel width on uplift forces is relatively complicated.Result shows that the relative panel width(i.e.,the ratio of panel width to wave length)plays a more important role in estimating the wave uplift force.Based on our comprehensive laboratory measurements,we further developed an empirical formula to compute wave uplift force on horizontal panels through dimensionless analysis.Compared with other empirical formulas,this formula uses dimensionless variables of clear physical meanings,thus can describe the interaction between waves and the panels in a better way.In addition,the efficiency of the formula to estimate wave uplift force on horizontal panels is verified against existing works.Therefore,the findings in this study shall be useful for understanding the mechanism of wave uplift force on horizontal panels and numerical model validation.  相似文献   

14.
A laboratory setup was developed to investigate irregular wave uplift loads on exposed high-pile jetties.It is shown that the dimensionless uplift load increases to the maximum with an increasing relative clearance and then decreases.The relative clearance corresponding to the peak force is linked to a range from 0.4 to 0.8.When the relative clearance exceeds a certain value,the wave can not reach the underside of the deck and the force becomes zero.Distinct trends of dimensionless force with a relative width of deck show that the force tends to decrease as the relative deck width increases,and then the decrease slows down after the relative deck width increases or decreases to a certain value.The pressure distribution length associated with the maximum uplift force is equivalent to the wave contact width x.When x is larger than the width of deck B,it is taken as B.The statistical distribution of loads obeys the Weibull distribution.The results from the analyses of the real data suggest a new dimensionless prediction model on wave-in-deck uplift loads and the conversion ratio between wave loads at different exceedance probabilities.A comparison is made between the new prediction model and the existing widely used three prediction models.These results are used as useful references for structural design of the jetty.  相似文献   

15.
The analysis of the data of model tests of two large deep wharves and monographic experimental studies show that two aspects are to be improved so as to predict the wave uplift forces on the bottom of a circular cylinder. The first aspect is the uplift pressure distribution on the bottom, and the second is the correct determination of the phase for maximum horizontal wave forces. The second problem has been solved. Synthesizing the results of theoretical analysis and experiments, we suggest a diagram for the determination of the phase when the maximum horizontal wave force appears. On the basis-ef the diagram the simultaneous wave uplift forces can be obtained for the structural stability analysis.  相似文献   

16.
A series of experimental studies about the force of internal solitary wave and internal periodic wave on vertical cylinders have been carried out in a two-dimensional layered internal wave flume. The internal solitary waves are produced by means of gravitational collapse at the layer thickness ratio of 0.2, and the internal periodic waves are produced with rocker-flap wave maker at the layer thickness ratio of 0.93. The wave parameters are obtained through dyeing photography. The vertical cylinders of the same size are arranged in different depths. The horizontal force on each cylinder is measured and the vertical distribution rules are researched. The internal wave heights are changed to study the impact of wave heights on the force. The results show that the horizontal force of concave type internal solitary wave on vertical cylinder in the upper-layer fluid has the same direction as the wave propagating, while it has an opposite direction in the lower-layer. The horizontal force is not evenly distributed in the lower fluid. And the force at different depths increases along with wave height. Internal solitary wave can produce an impact load on the entire pile. The horizontal force of internal periodic waves on the vertical cylinders is periodically changed at the frequency of waves. The direction of the force is opposite in the upper and lower layers, and the value is close. In the upper layer except the depth close to the interface, the force is evenly distributed; but it tends to decrease with the deeper depth in the lower layer. A periodic shear load can be produced on the entire pile by internal periodic waves, and it may cause fatigue damage to structures.  相似文献   

17.
新型开孔工字板组合式防波堤波浪力特性试验研究   总被引:1,自引:1,他引:0  
开孔工字板组合式防波堤是基于透空板式防波堤的一种新型结构形式,具有自重轻、材料省的特点。为充分了解新型开孔组合式防波堤的受力特性,基于室内水槽物理模型试验,测量新型开孔工字板组合式防波堤上的波压力与结构总力,研究相对波高H/d、相对波长L/B对该新型防波堤结构表面压力的影响,讨论了该新型防波堤所受波浪力荷载与相对波高H/d、相对波长L/B的关系。结果表明,相对波高H/d是决定新型防波堤结构表面波压力和结构总力的主要影响因素。该新型防波堤结构波浪力荷载以垂直方向受力为主,新型防波堤结构所受竖向总力远大于水平总力,最大可达到15倍。新型防波堤水平总力随相对波长L/B先增大后趋于稳定。相对波长L/B=3.617是防波堤结构水平总力变化幅度的分界点。  相似文献   

18.
圆柱形沉浮式深海养殖网箱的受力分析   总被引:9,自引:0,他引:9  
应用一系列力学关系,研究了深海圆柱形沉浮式养殖网箱所承受的波浪力情况。导出深海沉浮式养殖网箱的运动方程,并给出数值计算。在网箱波浪力的研究中采用绕射理论和Morison方程,讨论了在波高、波长及周期变化下水动力的变化趋势,得出网箱所受到的水平波浪力远大于竖直波浪力,波高的变化对波浪力的影响最大的结论,为深海网箱的设计校核提供1种参考方法。  相似文献   

19.
Computation of solitary waves during propagation and runup on a slope   总被引:1,自引:0,他引:1  
A numerical time-simulation algorithm for analysing highly nonlinear solitary waves interacting with plane gentle and steep slopes is described by employing a mixed Eulerian–Lagrangian method. The full nonlinear free surface conditions are considered here in a Lagrangian frame of reference without any analytical approximations, and thus the method is valid for very steep waves including overturning. It is found that the runup height is crucially dependent on the wave steepness and the slope of the plane. Pressures and forces exerted on impermeable walls of different inclinations (slopes) by progressive shallow water solitary waves are studied. Strong nonlinear features in the form of pronounced double peaks are visible in the time history of pressure and force signals with increasing heights of the oncoming solitary waves. The effect of nonlinearity is less pronounced as the inclination of the wall decreases with respect to the bottom surface.  相似文献   

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