深圳河河口围垦对防洪和河床冲淤影响研究   总被引：6，自引：0，他引：6  

彭世银 《海洋工程》2002,20(3):103-108

为研究深圳河河口福田保税区围垦填土占用部分河道对深圳河治理工程的影响 ,建立了贴体坐标系下平面二维的深圳河河道 -河口 -海湾整体水域的水流泥沙数学模型 ,计算了不同频率洪峰流量和河口潮位过程组合下河口围垦所造成的深圳河沿程水位抬高程度和河床冲淤变化情况 ,提出了建议的挖除方案  相似文献   

Gradation affects basic mechanical characteristics of Chinese calcareous sand as airport subgrade of reefs     

Shen Yang  Xue Shen  Hanlong Liu  Huayang Ge  Xiaoxi Rui 《Marine Georesources & Geotechnology》2020,38(6):706-715

Abstract

Construction of the reefs in the South China Sea is a significant foundation to the secure stability and economic development of China. The construction of an airport runway is necessary for this realization. The calcareous sand is the main primary material in the runway construction. A certain type of calcareous sand near a certain reef of the South China Sea was studied in this paper. To investigate this specific calcareous sand, quartz sand was used as a reference for comparison. Microscopic 3-D imaging, compression and triaxial tests were conducted to test the micro, squeezing and shear properties. The effect mechanism of gradation on the calcareous sand’s compressibility and shear characteristics are discussed from a mesoscopic viewpoint using 3-D morphology. Calcareous sand particles are multiangular and flatter in comparison with quartz sand. The larger the particle sizes are, the more different the two sands’ morphologies are. The compressibility of calcareous sand is greater, and the effect of the coarse fraction (5–1?mm) content in the gradation plays the most significant role in this feature. When the coarse particles’ content is less than 25% and the mass ratio of the middle and fine particles (M) is constant, there is the worst coarse fraction content causing the calcareous sand to be most likely compressed. The worst coarse fraction content decreases with the increase in M, and an empirical formula is proposed. When the gradation, relative density and confining pressure are the same, the peak shear stress and strain of calcareous sand are all at a high level. The effect of confining pressure is manifested in calcareous sand. The shear strength and dilation of calcareous sand are also most affected by the medium coarse fraction (5–0.25?mm) content.  相似文献   

厦门港疏浚弃土吹填造陆物理模型试验研究   总被引：2，自引：0，他引：2  

徐啸  崔峥  毛宁 《台湾海峡》2004,23(3):360-368

通过厦门港潮汐水流整体物理模型试验，掌握了厦门港十万吨级深水航道二期工程疏浚弃土吹填造陆各方案实施前后港池航道水流流态，为规划设计单位和决策部门利用疏浚弃土吹填造陆提供可靠的科学依据，试验结果表明，海沧吹填工程可作为一期吹填方案，鸡屿西吹填造陆工程可作为海沧吹填工程的后续工程，仅从水流角度考虑，象鼻嘴吹填造陆方案1是可行的。  相似文献   

Biological characteristics of a resident population of Atlantic cod (Gadus morhua L.) in southern Labrador     

Morris  Corey J.; Green  John M. 《ICES Journal of Marine Science》2002,59(4):666-678

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半封闭海湾潮间带部分围垦后纳潮量计算的商榷——以胶州湾为例   总被引：14，自引：1，他引：14  

杨世伦  陈启明  朱骏  张经 《海洋科学》2003,27(8):43-47

传统的海湾(泻湖)纳潮量计算方法不能精确地反映潮间带被部分围垦后纳潮量的实际情况,本考虑围堤的影响,将纳潮量分解为堤基以下的“梯形”区和堤基以上的“矩形”区两部分之和,在理论上更加严密。根据改进后方法算出的胶州湾近期纳潮量比传统方法算出的纳潮量大15％左右。可见,半个多世纪以来胶州湾的纳潮量只减少了约15％．而不是传统方法得出的约25％。  相似文献   

海岸带空间要素分析查询系统构建研究——以山东莱州湾为例     

黄卫民  王瑞富  张培文  张杰 《海洋科学进展》2001,19(4):81-85

海岸带开发与保护是我国保持海岸带可持续发展所急需解决的问题。以莱州湾为示范区 ,利用 GIS技术建立海岸带空间要素分析查询系统 ,旨在为实施海岸带的综合管理构建一个高技术支撑的信息分析系统  相似文献   

Study on Key Technology of Using Shell Sand as Backfill for Sea Reclamation   总被引：1，自引：0，他引：1  

郦能惠瞿亦容  何文钦陈晖 《中国海洋工程》2005,19(4):647-658

1 .IntroductionEpicontinental sea or land could formfromcontinental shelf because of the decreasing sea levelduring Quaternary.There is a large-area shell sand deposit more than ten meters thick in the neriticzone of China .To use the abundant marine shell sandresource as engineering material for ocean engi-neering and port engineeringis veryimportant .Sand (Gred and Bjorn,1999) ,fine sand (Zhangetal .,2002) , mediumand coarse sand (Qiuet al .,1995) ,highly weathered stone ballast (Zhanetal…  相似文献   

靖远矿区采煤沉陷区复垦综合评价方法研究   总被引：1，自引：0，他引：1  

刘学成  韩书才 《中国煤炭地质》2008,(8):47-49

以靖远矿区为例,从土地复垦和恢复生态学的角度出发,建立了靖远矿区采煤沉陷区复垦综合评价系统,选择土壤条件（土层厚度、土壤质地、有机质含量、土壤水分）、地形改造条件（地面坡度、地表破坏程度、改造难易程度）、气候及水文条件（年降雨量、灌溉条件）作为分类及评价因子对复垦潜力进行评价。将采煤沉陷地分为四种潜力区,对每种潜力类型区的复垦开发利用方向进行了优化设计,从理论上和实践上对靖远矿区采煤沉陷地的复垦能力以及复垦过程中用地结构的优化作了探讨,以期对当地沉陷地的复垦提供一定的科学依据。  相似文献   

Assessment of Marine Clay Improvement Under Reclamation Fills by in-situ Testing Methods     

A. Arulrajah  H. Nikraz  M. W. Bo 《Geotechnical and Geological Engineering》2006,24(2):219-226

In ground improvement projects with prefabricated vertical drains, the duration of the preloading period is set in advance based on the predetermined time rate of consolidation of the compressible layer. If prediction is accurately done, the required degree of consolidation is met at the pre-determined preloading time. As such, there is a requirement for in-situ tests to be carried out just prior to the removal of surcharge to assess the degree of consolidation of the improved ground. In-situ tests were carried out after 23 months of surcharge loading at the In-Situ Test Site within the Changi East Reclamation Project in the Republic of Singapore. In-situ testing works in this research study comprises the use of field vane shear, piezocone, flat dilatometer and self-boring pressuremeter. The in-situ tests were carried out to determine the shear strength and degree of consolidation of the Singapore marine clay at Changi after 23 months of surcharge loading. The In-Situ Test Site consisted of a Vertical Drain Area as well as an untreated Control Area. Both areas were located adjacent to each other and were surcharged simultaneously to the same level and surcharge left in place for a period of 23 months. Comparison was made between the in-situ test results of the Vertical Drain Area and the untreated Control Area.  相似文献   

巨石、中粗砂填海区风动潜孔锤引孔钻进工艺应用的研究     

王平  彭晓阳等 《地质与勘探》2002,38(5):74-77,85

通过成功地解决深圳市好湾电厂（二期）基础工程H型桩沉入困难问题，使用各种风动潜孔锤在巨石、中粗砂填海区进行了引孔钻进工艺的试验研究及应用，对风动潜孔锤钻进工艺及其机具的使用作了进一步的分析研究，提出了风动潜孔锤使用过程中工艺方面的改进措施。  相似文献