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弧板式透空堤消浪性能影响因素数值研究 总被引：1，自引：0，他引：1
弧板式透空堤是由弧型板组成的新型防波堤结构。为探讨其透射系数的影响因素,利用Fluent软件基于N-S方程构建了波浪与板式透空堤相互作用的数值模型,讨论了相对潜深、入射波周期、相对波高、相对板宽和结构型式对透射系数的影响。结果表明:弧板式透空堤的透射系数随着相对波高和入射波周期的增大而增大,在静水面附近透射系数最小,尤以静水面和略高于静水面时的消浪效果最佳;在相同波浪要素条件下,静水面及其上0.02 m和0.04 m位置处,弧板式透空堤的消浪效果明显优于平板式透空堤。 相似文献
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宽肩台式无人工护面块体的抛石防波堤是一种新型结构的斜坡堤,它是靠在波浪长期作用下最终形成的动力平衡断面来防浪的。大连北良粮食中转港系银行贷款建设的项目,该港的防波堤采用了宽肩台式结构,这在我国尚属首例。本文为该港宽肩台式防波堤设计方案稳定性的试验研究成果。 相似文献
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Based on the idea of disturbing the water motion in the upright direction, a new kind of multiple-layer breakwater is proposed in this article, which mainly consists of several horizontal plates. The breakwater's performance of dissipating waves has been investigated in detail in the regular wave tests. The factors identified with the characteristics of the breakwater are discussed, such as the relative width, the wave steepness and the models geometrical parameters (the width and the gap). The comparison and analysis of the transmission and reflection coefficients with respect to different factors are presented. The model test results indicate that the multiple-layer breakwater has the good characteristic of dissipating waves. Further more, only in a little extent can it reflect the waves. The multiple-layer breakwater proposed in the paper is very significative to promote the open type breakwater to be the permanent wave attenuator in the application. 相似文献
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圆弧板透空式防波堤消波性能试验研究 总被引：1，自引：1，他引：0
提出了一种由多层圆弧板组成的新型透空式防波堤结构,并对其在二维规则波浪作用下的消波性能进行了物理模型试验研究。在不同入射波高条件下,对圆弧板和水平板透空结构的消波性能进行了比较分析,探讨了圆弧板间距和层数对圆弧板透空式结构消波性能的影响。研究结果表明,圆弧板透空式结构的消波效果优于水平板式透空结构,在相对宽度为0.2时,可以使透射系数达0.5以下。随着圆弧板间距从0.15 m减小到0.05 m时,消波效果逐步提升,而圆弧板的层数对结构的消波性能也有一定影响。 相似文献
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Weng Keqin Senior Engineer Planning Desining Institute for Water Transportation Ministry of Communications Beijing 《中国海洋工程》1992,(2)
- In this paper, some problems in the design of the breakwater for Dayaowan port area are described including the optimal selection of the layout plan of the breakwater; the selection of structural type of the breakwater, the concrete block type for bank protection, the reversed L-shape parapet; the elevation of the parapet; the stability test of the whole revetment; as well as wave absorbing effects of the perforated 相似文献
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直立式防波堤堤头在斜向波浪作用下波浪力的计算在现行的技术规范中尚属空白。通过物理模型试验给出了堤头结构设计所需的波压分布图，指出了波浪入射方向和地形对堤头所受波浪力的贡献有时可以超过波高和波周期，根据现行规范按波浪正向入射计算堤头所受的波浪力偏于安全。 相似文献
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Li Chunzhu Shi Hongda Yu Dingyong Wang Aiqun
Professor Engineering College Ocean University of Qingdao Qingdao
Lecturer Engineering College Ocean University of Qingdao Qingdao
Senior Engineer Engineering College Ocean University of Qingdao Qingdao 《中国海洋工程》1997,(1)
Standing waves are formed due to the reflection when waves meet vertical wall,thereforestrong structures are needed to keep the wall stability under the serious wave attack.For the improvementof the working condition and increase of the stability of the wall,the lower reflecting breakwaters have at-tracted close attention Reports mostly from Japanese researchers are often concerned with the wall ofcaisson equipped with open windows.In this paper a kind of hollow-pipe perforated breakwater is exam-ined which waves may partially perforate into the harbour basin.The wave in front of the wall can onlyform partial standing wave and wave force is reduced obviously.And the theoretical calculation of waveforce and analysis of wave force spectrum are all derived.Comparison between the results from theoreticalcalculation and hydraulic modeling shows reasonable agreement. 相似文献
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In the dynamic stability analysis of a caisson breakwater, most of current studies pay attention to the motion characteristics of caisson breakwaters under a single periodical breaking wave excitation. And in the lifetime stability analysis of caisson breakwater, it is assumed that the caisson breakwater suffers storm wave excitation once annually in the design lifetime. However, the number of annual severe storm occurrence is a random variable. In this paper, a series of random waves are generated by the Wen Sheng-chang wave spectrum, and the histories of successive and long-term random wave forces are built up by using the improved Goda wave force model. It is assumed that the number of annual severe storm occurrence is in the Poisson distribution over the 50-year design lifetime, and the history of random wave excitation is generated for each storm by the wave spectrum. The response histories of the caisson breakwater to the random waves over 50-year design lifetime are calculated and taken as a set of samples. On the basis of the Monte Carlo simulation technique, a large number of samples can be obtained, and the probability assessment of the safety of the breakwater during the complete design lifetime is obtained by statistical analysis of a large number of samples. Finally, the procedure of probability assessment of the breakwater safety is illustrated by an example. 相似文献
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A numerical model is presented in this study to investigate the wave transformation over a submerged permeable breakwater on a porous slope seabed. For this purpose, the time-dependent mild-slope equation is newly derived for waves propagating over two layers of porous medium. This new mild-slope equation involves the parameters of the porous medium, and it is a type of hyperbolic differential equation, therefore numerically efficient. The validity of the present model is verified based on the comparisons with the previous experiments. The effects of the permeable properties of both the porous seabed and the submerged permeable breakwater are discussed in detail. The geometry of the submerged permeable breakwater to the wave transformation is also investigated based on the numerical solutions. 相似文献
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Transmitted and reflected coefficients for horizontal or vertical plate type breakwater 总被引：2，自引：0，他引：2
Surface or submerged horizontal or vertical plate can be considered as a new concept breakwater.This paper investigates the wave-plate interaction of this type of breakwater by use of the boundary element method.The relationships of wave transmitted and reflected among plate thickness,submergence and length are carefully studied by numerical simulation.It is shown that:(1) The transmitted coefficients of submerged horizontal plate or vertical plate will become larger with the increase of plate thickness and reduce rapidly with the decrease of plate submergence.(2) Both surface horizontal and vertical plate are efficient for intermediate and short wave elimination,but vertical plate is more effective.(3) Submerged horizontal plate can act more effectively than submerged vertical plate does.With all wave frequencies,the vertical plate almost has no wave elimination effect. 相似文献
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A numerical assessment study of tsunami attack on the rubble mound breakwater of Haydarpasa Port, located at the southern entrance of the Istanbul Bosphorus Strait in the Sea of Marmara, Turkey, is carried out in this study using a Volume-Averaged Reynolds-Averaged Navier-Stokes solver, IHFOAM, developed in OpenFOAM® environment. The numerical model is calibrated with and validated against the data from solitary wave and tsunami overflow experiments representing tsunami attack. Furthermore, attack of a potential tsunami near Haydarpasa Port is simulated to investigate effects of a more realistic tsunami that cannot be generated in a wave flume with the present state of the art technology. Discussions on practical engineering applications of this type of numerical modeling studies are given focusing on pressure distributions around the crown-wall of the rubble mound breakwater, and the forces acting on the single stone located behind the crown-wall at the rear side of the breakwater. Numerical modeling of stability/failure mechanism of the overall cross-section is studied throughout the paper.The present study shows that hydrodynamics along the wave flume and over the breakwater can be simulated properly for both solitary wave and tsunami overflow experiments. Stability of the overall cross-section can only be simulated qualitatively for solitary wave cases; on the other hand, the effect of the time elapsed during tsunami overflow cannot be reflected in the simulations using the present numerical tool. However, the stability of the overall cross-section under tsunami overflow is assessed by evaluating forces acting on the rear side armor unit supporting the crown-wall of the rubble mound breakwater as a practical engineering application in the present paper. Furthermore, two non-dimensional parameters are derived to discuss the stability of this armor unit; and thus, the stability condition of the overall cross-section. Approximate threshold values for these non-dimensional parameters are presented comparing experimental and numerical results as a starting point for engineers in practice. Finally, investigations on the solitary wave and tsunami overflow experiments/simulations are extended to the potential tsunami simulation in the scope of both representation of a realistic tsunami in a wave flume and stability of the rubble mound breakwater. 相似文献
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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
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Gu Hanbin Sun Jingshi
Engineer Tianjin Research Institute of Water Transport Engineering Tanggu: Professor Tianjin Research Institute of Water Transport Engineering Tanggu: 《中国海洋工程》1995,(4)
This paper introduces a new kind of armour block - hexagon multihole block on sloping breakwater. It has great characteristics such as good interlocking, strong resistance against waves and saving concrete. Through the hydraulic model test, the mechanism of stability of the block has been proved and the relations between stability and wave height, wave period, water depth, slope, laying method, porosity and cushion have been found. The effect of weight on steadiness have also been discovered. Finally, the method of design and some formulas are given. 相似文献
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Wang Jianyi
Ge Zhijin Senior Engineer River Harbour Department Nanjing Hydraulic Research Institute Nanjing 《中国海洋工程》1993,(2)
- This paper describes the design of a permeable caisson breakwater with slanting slabs (Types I and 11) and presents some preliminary experimental results, together with relevant figures and tables. Analysis is made of the reflection coefficient, transmission coefficient, acting wave pressures, water jetting at the crest of the breakwater, and wave overtopping. Experiments show conclusively that this type of breakwater has the advantages of light dead weight, good wave-absorbing performance, low coefficients of reflection and transmission, and small wave overtopping. 相似文献
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WANG Yuanzhan 《中国海洋工程》2001,(2):205-216
The possible motions of a caisson breakwater under dynamic load excitation include vibrating, vibrating-sliding and vibrating-rocking motions. The models of vibrating motion and vibrating-sliding motion have been proposed in an early paper. In this paper, a model of vibrating-rocking motion of caisson breakwaters under breaking wave impact is presented, which can be used to simulate the histories of vibrating-rocking motion of caisson breakwaters. The effect of rocking motion on the displacement, rotation, sliding force and overturning moment of breakwaters is investigated. In case the overturning moment exceeds the stability moment of a caisson, the caisson may only rock. The caisson overturns only in case the rocking angle exceeds the critical angle. It is shown that the sliding force and overturning moment of breakwaters can be reduced effectively due to the rocking motion. It is proposed that some rocking motion should be allowed in breakwater design. 相似文献