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 共查询到19条相似文献,搜索用时 93 毫秒
1.
Explosion for the treatment of underwater soft foundation is a technique newly developed in China. This paper describes the application of the method of explosion to underwater soft foundation treatment of the Great-West Dyke, Lianyungang Port, including the technical characteristics and the effect, selection of explosion parameters, workmanship of construction, requirements of quality and inspection, and the like.  相似文献   

2.
The The Great-West Dyke with a length of 6.7 km, the largest sea wall in China, was completed in June, 1994. This paper introduces structure options of nibble mound sea wall on soft foundation and a new type of armour block-hexagon multihole block (HMB) and a new method of treatment for soft foundation by using underwater explosion. Construction practice of some projects in China shows that by using this method good effect of treatment and marked economic benefit can be achieved by using this method.  相似文献   

3.
Erective Sea Embankment with PCC Piles   总被引:2,自引:0,他引:2  
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4.
Composite bucket foundation and one-step installation technology for offshore wind turbine are the integration of foundation construction, transportation and whole installation at sea. The cost of offshore wind turbine construction and installation has been largely reduced. Foundation stability is the key technology in the process of towing transportation. Field observation data can reflect the real state of the foundation. In this paper, the influence of water depth and towing speed on liquid l...  相似文献   

5.
- At the sites of the harbours along the coast of China, especially in the vicinity of the mouth of the Yellow River, the Yangtze River and the Pearl River, the soil strata often consist of recently deposited alluvial sediment. Therefore, under the foundations of harbour engineering structures there are always soft clays of considerable thickness. In this paper, the definition of soft clay is at first given according to the Chinese Foundation Code of Harbour Engineering. Then the physical and mechanical properties of some soft clays at the sites of harbour along the coast of China are summarized. These soft clays are classified into four types according to their physico-mechanical characteristics: very soft clay (mud), soft (muddy) clay, soft (muddy) silty clay and very soft clay (mud) mixed with lumps of sand. It is seen from the collected data that the physico-mechanical characteristics for soft clay of the same type at various sites along the coast of China are very similar, which implies that these soft clays may be formed from the similar geological origin and in similar environmental condition. It is well known that the soft clay with such unfavourable engineering properties as high water content, low shear strength, high compressibility and low permeability, is a rather weak foundation for structures, hence there would be frequently some problems happened during the construction of structure on it. However, these problems more or less can be avoided, provided that the soft clay strata have been explored, tested and analyzed carefully and appropriate measures are taken during construction. The problems usually encountered in the construction on soft clay are deformation and stability. The experiences and lessons learned on these respects in China are illustrated with 10 case histories of different types.  相似文献   

6.
Strengthening soft foundation by vacuum loading from lower position is a new method of ac-celerating the consolidation of dredger fill.This paper presents the mechanism of soft foundation strength-ening by vacuum loading from lower position and evaluates the effectiveness of this method under variousboundary conditions by means of finite element method(FEM)on the basis of Biot's consolidationtheory.  相似文献   

7.
In this paper, the foundation soil of offshore structure is simulated as a two phase saturated porous medium. The dynamic equations of porous medium and finite element formulation are given. For structural analysis, the technique of multilevel substructure is used, and the saturated soil analysis is set in the highest level substructure model. Based on these theories a dynamic finite element analysis program DIASS for the analysis of interaction between two phase ocean soil foundation and platform structures has been developed. A numerical example is given here to illustrate the influence of the pore water in soil on the structural response of an ocean platform.  相似文献   

8.
The three-bucket jacket foundation is a new type of foundation for offshore wind turbine that has the advantages of fast construction speed and suitability for deep water. The study of the hoisting and launching process is of great significance to ensure construction safety in actual projects. In this paper, a new launching technology is proposed that is based on the foundation of the three-bucket jacket for offshore wind turbine. A complete time domain simulation of the launching process of thr...  相似文献   

9.
The vibration characteristics of offshore gravity structure foundations due to storm waves and some corresponding considerations are discussed in this paper. In view of some chief defects in the current methods of stress analysis for evaluating soil liquefaction potential and in order to study the problems of complex vibrations, the energy analysis procedure previously presented by the author is introduced herein. Since the imposed loads on foundation are random in nature, the technique of predicting sand liquefaction potential under random vibrations based on that induced by harmonic vibration conditions is studied in this paper. In respect of the long-term vibration and better drainage conditions, it is very important to take into consideration the pore water pressure dissipation and redistribution during and after the period of vibration. In fact, under these conditions the pore water pressure dissipation and redistribution may prevent the foundation from liquefying.  相似文献   

10.
The vibroflotation technique has now become a comparatively perfect method. However, the stone column driving at the sea bottom, which is liable to ebb and flood tides, is seldom tried abroad and has been tried for the first time at home. We have designed a set of construction techniques for driving and installing stone columns at sea. These techniques have been proved successful and highly efficient by practice. At the sea bottom were conducted three groups of large-scale loading tests and the allowable bearing capacity of the composite foundation was obtained as 130 kPa, against that of the natural foundation: 50 kPa. The allowable bearing capacity of the composite foundation showed 2.6 times as much as that of the natural foundation. Also obtained was the distribution ratio of stress, n = 3. The experience and indexes, obtained from the Yantai Harbour Project, have already been justified in the application in reinforcing the coastal highway at the Huaneng Power Plant of Fuzhou City, Fujian Province.  相似文献   

11.
朱继伟 《海岸工程》2008,27(3):72-76
重力式码头基床爆破夯在深基床的情况下,具有更明显的优势。结合广州港南沙港区二期工程深基床爆夯的应用,对爆夯法加固深基床进行了效果分析,并提出需要探讨的几个问题。  相似文献   

12.
陈海 《海岸工程》1999,18(4):64-67
青岛市中港东区码头工程水下爆岩工程量1.3万m^3,施工中采用了多段微差爆破,毫秒延迟爆破,导爆管起爆等多项为先进和成熟的施工技术,合理的施工组织,完善的施工管理,保证了工程质量,加快了工程进度。  相似文献   

13.
爆破挤淤是处理淤泥质软基的常用方法,而研究由此产生的悬浮泥沙的输移扩散对于评价施工对工程区水环境的影响有重要意义。在对爆破挤淤产生的悬浮泥沙对水环境影响初步分析的基础上,就防波堤地基爆破挤淤处理产生的悬浮泥沙在波浪、潮流共同作用下的输移扩散过程进行了数值模拟,并对爆破挤淤后悬浮泥沙输移扩散规律进行了探讨,指出爆破挤淤对水域附近的生态环境有一定影响,但影响范围并不大,且持续的时间亦不长。  相似文献   

14.
肖飞  范先力 《海岸工程》1999,18(3):39-41
介绍了前湾港一期工程杂货码头港池炸礁情况,证实了水大型码头在主体工程完成后,进行港池内礁岩爆破作业作可行性和必须采取的技术措施。  相似文献   

15.
海涂围垦工程中悬挂式爆破挤淤基础处理技术探讨   总被引:1,自引:0,他引:1  
沿海软土地基围涂工程中悬挂式爆破挤淤基础处理断面结构设计中遇到的最大难题是对腰宽的处理,腰宽太窄则工后沉降大,反之,则断面石方量增大,投资增加,因此,试图通过工程实例说明悬挂式爆破挤淤基础处理断面设计及工程实施过程中遇到的问题及对策措施。  相似文献   

16.
Whipping response will happen when a ship is subjected to underwater explosion bubble load. In that condition, the hull would be broken, and even the survivability will be completely lost. A calculation method on the dynamic bending moment of bubble has been put forward in this paper to evaluate the impact of underwater explosion bubble load on the longitudinal strength of surface ships. Meanwhile the prediction equation of bubble dynamic bending moment has been concluded with the results of numerical simulation. With wave effect taken into consideration, the evaluation method of the total damage of a ship has been established. The precision of this evaluation method has been proved through the comparison with calculation results. In order to verify the validity of the calculation results, experimental data of real ship explosion is applied. Prediction equation and evaluation method proposed in this paper are to be used in ship structure design, especially in the preliminary prediction of the ultimate withstanding capability of underwater explosion damage for the integrated ship in preliminary design phase.  相似文献   

17.
山东全新世滨海软土与工程地质灾害的研究   总被引:2,自引:0,他引:2  
山东全新世滨海软土分布在海湾、泻湖、河口区,厚度1-10m。海湾、泻湖软土为淤泥、淤泥质土,陆源物质供应丰富的浅水区,软土颗粒偏粗,强度相对较高,触变性对建筑物危害性大,陆源物质供应少的深水区,软土颗粒偏细,低强度、高压缩性、沉降变形大和蠕变性是危及建筑物稳定的主要因素。海湾、泻湖软土位于地下水位下,具低透水性,掩埋后短期不易排水固结,软土下为强度较高的冲积物,对一般建筑物,利用强夯、粉喷搅拌桩、  相似文献   

18.
It is well known that the accuracy of mesh-based numerical simulations of underwater explosion strongly relies on the mesh size adopted in the analyses. Although a numerical analysis of underwater explosion can be performed with enough accuracy by using considerably fine meshes, such fine meshes may lead to substantially increase in the CPU time and the usage of computer memory. Thus, how to determine a suitable mesh size in numerical simulations is always a problem confronted when attempting to study the shock wave propagation resulting from underwater explosion and the subsequent response of structures. Considering that there is currently no universally accepted method for resolving this problem, this paper aims to propose a simple method to determine the mesh size for numerical simulations of near field underwater explosion. To this end, the mesh size effects on the shock wave propagation of underwater explosion are carefully investigated for different charge weights, through which the correlation between mesh sizes and charge weights is identified. Based on the numerical study, a dimensionless variable (λ), defined as the ratio of the radius of charge to the side length of element, is introduced to be the criterion for determining the mesh size in simulations. It is interesting to note that the presented method is suitable for various charge weights. By using the proposed meshing rule, adequate balance between solution accuracy and computational efficiency can be achieved for different blast scenarios in numerical simulations of underwater explosion.  相似文献   

19.
Stability of the Guiding Dike in Yangtze Estuary Under the Wave Load   总被引:3,自引:0,他引:3  
1 .IntroductionIt has beenrealizedthat constructing gravitystructures onsoft soil foundations is a difficult task,especiallyinthe marine area where boththe geological and environmental conditions are severe .Thisisnot only because the bearing capacity of the soft foundation is relatively low, but also because thestrength of the soft soil will befurther weakened bythe waveloading (Andersenet al .,1988 ;Ander-sen and Lauritzsen,1988 ; Yasuhara ,1988) .The strength weakening may cause serious d…  相似文献   

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