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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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Javier Lario Chris Spencer Teresa Bardají Ángel Marchante Victor H. Garduño-monroy Jorge Macias Sergio Ortega 《Sedimentology》2020,67(3):1481-1504
The Yucatán Peninsula, Mexico, has typically been considered a tectonically stable region with little significant seismic activity. The region though, is one that is regularly affected by hurricanes. A detailed survey of ca 100 km of the eastern Yucatán and Cozumel coast identified the presence of ridges containing individual boulders measuring >1 m in length. The boulder ridges reach 5 m in height and their origin is associated with extreme wave event activity. Previously modelled tsunami waves from known seismically active zones in the region (Muertos Thrust Belt and South Caribbean Deformed Belt) are not of sufficient scale in the area of the Yucatán Peninsula to have produced the boulder ridges recorded in this study. The occurrence of hurricanes in this region is more common, but two of the most destructive (Hurricane Gilbert 1988 and Hurricane Wilma 2005) produced coastal waves too small to have created the ridges recorded here. In this paper, a new tsunami model with a source area located on the Motagua/Swan Island Fault System has been generated that indicates a tsunami event may have caused the extreme wave events that resulted in the deposition of the boulder ridges. 相似文献
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The distribution and bioaccumulation features of PCBs, DDTs, and HCHs were investigated in the sediments and Manila clams collected from along the Mid-Western coast of Korea. The measured concentrations of ΣPCBs, ΣDDTs and ΣHCHs were 1.08–3.5, 0.12–0.35 and 0.090–0.30 ng g−1 dw in sediment, and 33–390, 7.4–46 and 6.3–27 ng g−1 lipid in Manila clam, respectively. Their levels were found to be relatively lower than those of other contaminated areas and the consumption of Manila clam from these areas seems to be safe for human health according to calculated lifetime cancer risk and hazard indices. The ΣPCBs and ΣDDTs concentrations in sediments showed a significant relationship to those in clams. The significant correlation was observed between BSAF in clams and Kow for each PCB congeners and DDT metabolites. These findings support that the PCBs and DDTs levels, which are highly hydrophobic chemicals, in clam reflect the sediment pollution through bioaccumulation. 相似文献
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天津市建设项目"海上地震观测试验系统",是"十五"期间天津数字地震观测网络项目中的重点实验任务,该项目的建设将有效提高渤海海域地震监测能力,为天津经济社会发展建设、为滨海新区开发开放提供服务.通过建设海洋地震台,提高了天津市测震台网在渤海地区的监控能力,对于海啸预警能力也大有提高. 相似文献
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龚家方4号斜坡涌浪数值模拟分析 总被引:2,自引:0,他引:2
对于库区滑坡来说,不能只考虑滑坡体本身造成的灾害,还要考虑滑坡体引起的涌浪灾害,为了研究滑坡涌浪的传播、衰减规律,在Geo-wave软件的技术上,二次开发形成FAST软件。以三峡库区龚家方4号斜坡为研究对象,分别在175、156、145 m的库水位条件下,在长约23 km、宽约10.4 km的区域内进行涌浪数值模拟,获得涌浪传播模拟数据。经过模拟软件数据处理模块的计算分析,形成了分析涌浪传播规律的一系列图件。对不同水位下涌浪模拟的计算结果进行对比分析发现,随着库水位的下降,滑坡产生的最大涌浪值和在对岸的爬高值都有增长的趋势,但其对航道存在威胁的时间逐渐变短。模拟区各位置的最大波高空间分布形态具有中间内凹、两翼沿岸坡延伸的特征。涌浪传播的急剧衰减区基本分布在涌浪源附近1 km的范围内,涌浪源处的波高越大,单位距离内的涌浪下降高度也越大。由于涌浪在岸边有叠加、壅高现象,建议航道内船只经过地质灾害点附近时应沿江中心快速通行。 相似文献
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本文基于TELEMAC-2D模型建立太平洋区域海啸传播模型,模拟2011年日本“3·11”海啸事件下海啸波的传播。使用实测数据对该模型进行验证,在模型验证良好的基础上分析日本“3·11”海啸事件对乐清湾的影响。通过频谱分析得到“3·11”海啸激发的乐清湾内240、180和103 min这3个主导模态的幅值及其相位。通过白噪声实验对乐清湾的固有共振特征进行估算,进一步支持了乐清湾在上述3个模态发生共振这一结论。白噪声实验还表明,海啸等海洋灾害发生时会在乐清湾湾顶及湾口处产生较大的增水,该结论对乐清湾内海洋灾害风险防范具有指导意义。 相似文献
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