漳州港码头岸线规划潮流及泥沙问题研究   总被引：1，自引：0，他引：1  

陈勇  刘家驹 《海洋工程》1996,(2)

本文在实测资料的基础上，全面分析了漳州港海域的波浪要素，潮流动力，泥沙运移特性和水深演变等，计算了漳州港码头工程前后潮流分布场，并在此基础上预报了漳州港起步工程的３．５万吨级码头泊位、港池、航道的泥沙冲淤幅度。结果表明，漳州港海域的水深维护主要与上游纳潮面积大小有关，海域潮差大，潮流强，水深大，波浪小，海域泥沙主要来源于上游的九龙江，年输沙量为２７７万ｔ，海域年平均含沙量也不大，港池航道水深可由水流动力来维持、泊位和淤积很小，这些情况表明，漳州港屿仔尾海区建港的自然条件是优越的。  相似文献   

Sediment rating parameters and their implications: Yangtze River, China   总被引：4，自引：0，他引：4  

Guifang Yang  Zhongyuan Chen  Fengling Yu  Zhanghua Wang  Yiwen Zhao  Zhangqiao Wang 《Geomorphology》2007,85(3-4):166

This study examines the characteristics of sediment rating parameters recorded at various gauging stations in the Yangtze Basin in relation to their controls. Our findings indicate that the parameters are associated with river channel morphology of the selected reaches. High b-values (> 1.600) and low log(a) values (< − 4.000) occur in the upper course of the steep rock-confined river, characterizing high unit stream power flows. Low b-values (< 0.900) and high log(a) values (> − 1.000) occur in the middle and lower Yangtze River associated with meandering reaches over low gradients, and can be taken to imply aggradation in these reaches with low stream power. Higher b-values (0.900–1.600) and lower log(a)-values (− 4.000 to − 1.000) characterize the reaches between Yichang and Xinchang, immediately below the Three Gorges. These values indicate channel erosion and bed instability that result from changes in channel gradient from the upstream steep valley to downstream low slope flood plain settings. Differences in channel morphology accompany these changes. Confined, V-shaped valleys occur upstream and are replaced downstream by broad U-shaped channels. The middle and lower Yangtze shows an apparent increase in channel instability over the past 40 years. This inference is based on sediment rating parameters from various gauging stations that record increasing b-values against decreasing log(a)-values over that time. Analysis of the sediment load data also reveals a strong correlation between changes in sediment rating curve parameters and reduction of annual sediment budget (4.70 × 10⁸ t to 3.50 × 10⁸ t/year, from the 1950s to 1990s), largely due to the damming of the Yangtze and sediment load depletion through siltation in the Dongting Lake. Short-term deviations from the general trends in the sediment rating parameters are related to hydroclimatic events. Extreme low b-values and high log(a)-values signify the major flood years, while the reverse indicates drought events. When compared with rivers from other climate settings, it is evident that the wide range of values of the Yangtze rating parameters reflects the huge discharge driven by the monsoon precipitation regime of eastern China.  相似文献   

Prediction of Siltation in the Downstream Approach Channel of Tidal Locks   总被引：1，自引：0，他引：1  

ZHANG Xingnong YANG Hong  SUN Bo Senior Engineer  River  Harbour Engineering Department  Nanjing Hydraulic Research Institute  Nanjing  P. R. China Engineer  River  Harbour Engineering Department  Nanjing Hydraulic Research Institute  Nanjing  P. R. China 《中国海洋工程》1999,(3)

Silt deposition occurs in the downstream approach,channel of the tidal lock as in a closed channelor excavated dock basin.It is often difficult to calculate or predict siltation because of complex flow and sedi-ment conditions and many other affecting factors.In this paper,the characteristics of flow movement in theapproach channel(including its mouth)of the tidal lock are analyzed,the basic laws of sediment movementand siltation mechanism are investigated,the conditions for three types of siltation(circumfluence siltation,density flow siltation and slow flow siltation)are discussed,and corresponding calculating formulas are pro-posed.A practical example shows that the difference between measured and calculated results is small,indi-cating that the present calculating methods could be used in design and management of practical engineeringprojects.  相似文献   

多波束测深系统在航道淤积计算中的应用     

许传新 《世界地质》2017,36(1):311-315

潍坊森达美港航道受2015年3月18日黄渤海风暴潮影响导致航道泥沙淤积,为推算泥沙淤积的数量,根据航道的吨级、长度、淤积程度,选取距离海岸线远近不同、淤积程度不同的三段航道采用多波束测深系统进行海下地形测量,与风暴潮到来之前的航道地形数据进行比对,计算出三段航道受风暴潮影响后泥沙的淤积数量,推算整个航道受风暴潮影响淤积量,从而评估风暴潮给航道施工单位带来的损失。  相似文献   

近20年来三峡水库泥沙淤积及其对库区的影响     

袁晶  许全喜  董炳江  王涛  杨成刚 《湖泊科学》2023,35(2):632-641

泥沙问题是三峡工程建设与运行中的关键技术问题之一,只有妥善处理好泥沙问题,才能保证三峡工程长期有效使用,维持水库功能的全面发挥。本文首先结合实测水文、河道地形观测资料,对三峡水库运行近20年来的泥沙淤积特性及水库排沙比进行了较为全面的分析研究,并与已有研究成果进行了对比;其次,围绕防洪、航运以及坝前段的泥沙淤积等方面,进一步分析了水库淤积产生的影响。结果表明:三峡水库蓄水以来,在不考虑区间来沙的情况下,三峡水库共淤积泥沙20.484亿t,近似年均淤积1.102亿t,水库排沙比为23.6%,水库年均淤积量为原论证预测值的33%。其中,库区干流段累计淤积泥沙17.835亿m³(变动回水区冲刷0.694亿m³;常年回水区淤积18.529亿m³),淤积在水库防洪库容内的泥沙为1.648亿m³(干、支流分别淤积1.517亿m³和0.131亿m³),占水库防洪库容的0.74%,“十一五”攻关阶段研究得出的多年平均淤积量及排沙比较实测值均偏大,变动回水区冲淤则出现反向的...  相似文献   

贵州安顺地区岩腊片区水淹坝岩溶内涝成因分析     

王瑶  王若帆 《四川地质学报》2020,40(1):125-129

水淹坝岩溶内涝是安顺市西秀区发育最大范围的岩溶内涝,严重制约了当地经济发展。本文以岩溶地下水系统为单元,通过开展1:10000水文地质调查、地球物理勘探、水文地质钻探等手段,查明内涝所在区的岩溶发育特征、水文地质条件。在此基础上分析得出,水力坡度小、岩层倾角缓造成地下河管道淤塞;人类工程活动使有水落水洞口堵塞,加之广阔的集雨面积和连续的强降雨是造成水淹坝岩溶内涝的主要原因。通过对水淹坝内涝成因分析,为岩溶内涝灾害综合整治提供参考依据。  相似文献   

长江口12.5米深水航道南坝田挡沙堤加高工程总平面方案研究     

应铭  季岚  曹慧江  王大伟 《海洋工程》2020,38(4):19-28

长江口12.5米深水航道2010年贯通后,发挥了巨大社会经济效益,同时航道回淤量大、维护压力大、维护费用高的问题突出。本研究基于北槽四边界水沙通量观测成果,分析提出了北槽航道回淤泥沙来源;针对回淤原因,在已建减淤工程经验总结的基础上,提出了本次减淤的研究思路,优化了减淤工程方案的比选指标体系;采用三维潮流泥沙数模、清水动床物模、经济技术综合分析等手段,通过"加高范围"、"加高高程"及"加高位置"比选,研究推荐了减淤工程方案。利用实测回淤量分析了工程减淤效果。研究结果表明,南导堤越沙是洪季北槽的重要泥沙来源,对北槽高浓度含沙量场有一定贡献。提出了可通过加高北槽南侧的导堤,实现减少通过南导堤越堤进入北槽的泥沙量,从而减小北槽含沙量水平,同时改善北槽下段流态,降低水沙横向输移,进而降低航道回淤的减淤思路。研究推荐的长江口12.5米深水航道减淤工程为南坝田挡沙堤加高工程及先期工程方案。先期工程位于S4～S9丁坝坝田,在现有南坝田挡沙堤的基础上加高S4～S8区段,并延长至S9丁坝,工程全长约23.8 km,高程+3.5 m。工程于2015年11月开工建设,2016年7月主体工程完工,工程减淤效果显著,2016—2018年年均减淤量约954×105m3/a,近三年已节省航道维护疏浚费用约5亿元。  相似文献   

A Novel Method for Real-Time Monitoring of Channel Siltation Based on Bistatic Scattering Theory     

侯朋  许文海  王俊生  李瑛 《中国海洋工程》2010,24(1):105-115

Monitoring the thickness changes of channel siltation is paramount in safeguarding navigation and guiding dredging.This paper presents a novel method for realizing the field monitoring of channel siltation in real time.The method is based on the bistatic scattering theory and concerned more with the receiving and processing of multipath signal at high-frequency and small grazing angle.By use of the multipath propagation structure of underwater acoustic channel,the method obtains the silt thickness by calculating the relative time delay of acoustic signals between the direct and the shortest bottom reflected paths.Bistatic transducer pairs are employed to transmit and receive the acoustic signals,and the GPS time synchronization technology is introduced to synchronize the transmitter and receiver.The WRELAX (Weighted Fourier transform and RELAX) algorithm is used to obtain the high resolution estimation of multipath time delay.To examine the feasibility of the presented method and the accuracy and precision of the developed system,a series of sea trials are conducted in the southwest coast area of Dalian City,north of the Yellow Sea.The experimental results are compared with that using high-resolution dual echo sounder HydroBoxTM,and the uncertainty is smaller than ±0.06 m.Compared with the existing means for measuring the silt thickness,the present method is innovative,and the system is stable,efficient and provides a better real-time performance.It especially suits monitoring the narrow channel with rapid changes of siltation.  相似文献   

泉州湾工程地质条件及港口规划建设的探讨   总被引：2，自引：2，他引：0  

何耀堂 《福建地质》2005,24(4):254-259

在介绍泉州湾工程地质条件的基础上,着重叙述其地质构造及地震地质环境、海岸线迁移和海湾淤积现状,从而对港口的规划建设和海湾的保护与合理开发进行分析和讨论。  相似文献   

粘性泥石流坝后回淤比降的实验   总被引：1，自引：0，他引：1  

吴鑫  马东涛  杨敏 《山地学报》2013,31(5)

拦挡坝坝后回淤比降是泥石流防治工程设计中的一个重要参数.本实验选取粘性泥石流,开展了沟床纵比降为9.5％～26.2％共8组和重度17～22 kN/m3共6组的坝后回淤比降的模拟实验.实验发现:1.在沟床纵坡为9.5％、12.1％、14.4％、16.7％、18.9％、21.3％、23.8％和26.2％时,其回淤比降分另为8.08％、9.8％、11.38％、12.69％、14.55％、16.61％、18.56％和20.96％;2.回淤比降比值在0.76至0.85间,平均0.80;3.回淤比降随沟槽纵比降的增大而增大,二者呈线性正相关,相关系数在0.95以上;回淤比降随重度的增大,总体呈缓慢增大的趋势,关系为二次函数关系.由此建立了回淤比降与重度和沟床纵比降的关系式:i=0.6014 ×γ0.0526 ×i00.9470,据此可以初步确定回淤比降的设计值.  相似文献