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在系统开展海洋区域地质调查的过程中，荷兰广泛使用了各种地球物理调查方法，并在方法选用、测线部署、资料处理和图件编制等方面有许多独到之处；对中荷两国的做法进行了系统的比较；对今后在我国海洋区域地质调查中如何开展地球物理调查工作提出了建议。 相似文献
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Gayle Hough Jennifer Green Paul Fish Andy Mills Roger Moore 《Marine Geophysical Researches》2011,32(1-2):151-162
Exploration and development of offshore hydrocarbon resources has advanced into remote deepwater regions over the last decade and poses significant technical challenges for the design and installation of wells and facilities at extreme water depths. Seafloor and shallow subsurface processes and conditions in these areas are complex and generally poorly understood, and the geohazards to development are larger scale and fundamentally different to those encountered onshore; consequently the geohazard risk to deepwater development projects is potentially significant and requires careful evaluation and mitigation during the front-end planning and engineering design stages of projects. There are no established industry standards or methods for the assessment of geohazards and engineering-quality geophysical data at the scale of development. The paper describes an integrated and systematic map-based approach for the assessment and mitigation of seabed geohazards and risk to proposed deepwater development. The approach employs a multi-disciplinary team working with engineering-quality field calibrated data to accurately map and assess seafloor ground conditions and ensure that development proposals are not exposed to intolerable geohazard risk. The approach taken is very similar to the practice of establishing geological models for land-based engineering projects, in which the complete geological history of the site is used to characterise and predict the performance of the ground. Such an approach is routine for major projects on land but so far does not seem to be common practice in the offshore industry. The paper illustrates the seafloor geomophological mapping approach developed. The products are being used to optimise development layouts to avoid geohazards where possible and to support site-specific engineering design of facilities based on a detailed understanding of the potential geohazard loadings and associated risk. 相似文献
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Subroto Kumar Bhattacharyya V.G. Idichandy Nitindra R. Joglekar 《Applied Ocean Research》1985,7(1):24-34
Load-out, launching and upending are major sequential installation operations of the offshore steel jackets. Due to vital engineering importance of these high risk operations, a thorough scientific understanding of their mechanics is desirable and a physical simulation approach using scaled models is a powerful method to achieve this end. This paper presents such an approach in the context of a case study which is oriented towards gaining adequate understanding of the modelling principles, model design and simulation of operations. It also highlights the role of decisive parameters as they affect the operational performance. Some of the experimental techniques of interest are also presented. 相似文献
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浮托安装法,是相对于传统吊装法的一种新型海洋平台安装方法,具有起重能力大、作业周期短、安装费用低、适用范围广、操作安全方便等优点,解决了海上大型平台组块的安装问题。为了研究横荡护舷对浮托安装的影响,首先对海洋平台浮托安装中的护舷装置进行了介绍,然后针对某工程实例应用AQWA软件进行了数值模拟,并进行了模型验证。从时域方面对就位状态下的浮托模型进行了耦合动力分析,研究了横荡护舷参数对驳船运动和撞击力的影响规律。研究表明,横荡护舷可以有效地减小驳船运动和撞击力,其限位和缓冲作用与护舷尺寸及护舷刚度均有关。研究结果可为实际浮托安装工程提供重要的参考。 相似文献
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Giovanni Spagnoli Chiara Bosco Pierpaolo Oreste 《Marine Georesources & Geotechnology》2017,35(2):266-274
Foundations of offshore oil and gas production platforms or wind parks are in the majority of cases piled-based. Piles are mainly driven to a certain design depth using hammers. However, there are many situations were driven piles cannot be properly installed. Plug formation or presence of rock layers and/or boulders preclude the correct installation. Since time is a key factor in offshore operations, offshore drilled piles are not very common. Their high level of uncertainty is mainly due to the complexity to assess a pile drillability analysis. For these reasons, assessing the drilling time needed to overcome the problems is very important. The following research compared first of all several well-known equations used for estimating the tunnel boring machine (TBM) excavation rate. Second, a novel approach has been used, which is based on the estimation of the specific energy. After having performed continuous automatic diagraphy tests in Turin subsoils (Italy), values of friction angles and compressive strength were obtained. Specific energy was calculated at the scale of the continuous automatic diagraphy test as a function of ξ, which is a coefficient depending on the geotechnical parameters assumed by Nishimatsu. It is therefore possible to estimate the drilling rate for different values of friction angle and cohesion. 相似文献
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利用MATLAB实时处理GPS数据 总被引：1，自引：0，他引：1
利用MATLAB软件环境,现场接收并实时处理海上地球物理调查过程中的GPS定位数据,剔除原始数据中的跳点,处理定位误差。采用样条拟合对测线进行拟合光滑,绘制各步处理结果的图形,并将处理前后的航向、航速数据及由此计算出的Eotvos改正值绘制成的曲线进行比较,结果表明:由原始数据计算得到的定位误差较大,与实际船体航行的轨迹有一定差距,而用经过MATLAB处理后的数据计算得到的定位误差较小,航向、航速等与船体航行的真实航迹接近,由此计算出的Eotvos改正值的精度也达到了海上重力测量中Eotvos改正的要求,保证了地球物理数据的质量。 相似文献
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近海湾口潮汐沉积特征通常以地质资料进行描述,而很少以地球物理资料进行描述。或仅利用某种地球物理资料进行分析。本文通过利用多波束、侧扫声呐、单道地震、多道高分辨率地震和磁法等多种地球物理勘探方法和技术,针对胶州湾近海湾口潮汐沉积的地球物理特征进行了初步研究,获得了近海湾口潮汐沉积典型的地球物理特征。 相似文献
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Parametric study on offshore jacket launching 总被引：1，自引：0，他引：1
Platform structures are commonly utilized for various purposes including offshore drilling, processing and support of offshore operations. Jacket type structures are attractive in relatively shallow water regions. A jacket is a supporting structure for deck facilities stabilized by leg piles through the seabed. The size of a jacket is dependent on deck size, pile dimensions and environmental loads. In a jacket design, operational and environmental loads are very important and must be investigated intensively to secure the stability of structures during their operation life, and installation phase as well. To confirm the stability, several analyses including in-place, fatigue, dynamic, load-out, transportation, lifting, and launching are performed. As the jacket weight and dimensions become large, a launching technique is applied to install the jacket. The launching analysis needs to consider quite a number of parameters including environmental conditions, launch barge specification, ballast, trim angle, local member integrity, etc. Due to the complexity of the operation, there is not a straightforward guideline or procedure for analysis. In this paper, a general procedure for analysis with various conditions and launching criteria are discussed and investigated. The effects of parameters are closely examined by numerical modeling. 相似文献
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Subroto Kumar Bhattacharyya 《Applied Ocean Research》1984,6(4):221-226
The role of similitude in scaled simulation of major installation operations of offshore steel jackets, namely, loadout, launching and upending has been studied. The physical modelling can be looked upon both as an adjunct to numerical modelling using computers and also as an independent tool of investigation. The problems of design of models and of experiments are discussed and the prediction equations based on similitude are given. 相似文献
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Methods for processing satellite data on ice features that pose a threat to the safety of offshore operations in the Arctic seas are considered. They are divided into interactive, automated, and automatic methods. The methods are illustrated by examples of archival satellite data on the Russian Arctic sector. Radar and optical data have been used as the satellite information source. It is shown that the successful satellite monitoring of dangerous ice features requires the optimal combination of satellite observations at various stages that provide for a synergistic approach to the data assimilation of different spectral bands obtained using different spacecraft. 相似文献
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Giovanni Spagnoli Cristina de Hollanda Cavalcanti Tsuha 《Marine Georesources & Geotechnology》2020,38(9):1013-1036
AbstractHelical piles are used mainly to resist tension forces generated by uplift and overturning moments of various structures, therefore they have been suggested as a potential alternative to driven piles as offshore pile because they provide a large uplift capacity due to the anchor effect of the helix. To date no standards are available for the assessment of the use of helical piles in the offshore environment. State-of-the art installation and uplift capacity assessment is based on field onshore tests on small helical piles. The purpose of this review is to critically evaluate the current knowledge on helical piles considering uplift capacity, cyclic load, installation torque models and the parameters affecting the installation torque, to understand whether they can be considered for potential offshore applications. The paper could be of valuable interest for engineers and contractors involved in the offshore installation of piles. 相似文献
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吸力基础与海洋工程大直径钢桩相比,具有成本低、安装周期短、对环境影响小、不受海况影响及可回收再利用等优点,近年来在海上风电工程中得到推广应用。吸力基础沉贯至海床预定位置,是其发挥承载力和确保服役稳定性的前提。海床地基土体常以分层土形式分布,且各层土体强度、压缩性和渗透性等存在显著差别,导致吸力基础吸力沉贯机理非常复杂。明确吸力基础在分层土中沉贯特性,有助于指导吸力基础在海上风电工程中的推广应用。对目前吸力基础在分层土中沉贯特性研究进行综述和总结,归纳了其沉贯机理研究进展,并对影响吸力基础在分层土中沉贯因素进行了分析;提出了分层土中吸力基础沉贯的研究方向和改进的沉贯方法。 相似文献
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海底浅层地质灾害的高分辨率地震识别技术 总被引：1，自引：0，他引：1
将渤海某油田最新采集的二维高分辨率资料处理解释后,结合区域地球物理及地质概况,利用地震相分析、波阻抗反演、井(孔)震标定等深层油气勘探的成熟技术,系统研究了各类海底浅层地质灾害因素的成因、特征、危害及展布规律,总结了一套完整的利用高分辨率地震识别海底浅层地质灾害的技术方法。结果表明,浅层断裂、浅层气和埋藏古河道是研究区海底浅层发育的主要地质灾害因素,通过刻画不同期次地质灾害因素的类型及其分布范围,为今后该油田海上施工提供了可靠的工程地质调查成果。因此,高分辨率地震技术能够很好地应用于海底浅层地质灾害的识别。 相似文献
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随着海洋资源的开采走向深海,海上平台需要面对更加恶劣的海洋环境,因此,需要平台的质量更大,结构更强。而如何安装这些大型平台成为工程施工的重要挑战。浮托安装法是大型平台安装的一种十分有发展前景的安装方法,在浮托安装过程中进行实时监测,可以为浮托安装提供直接的信息反馈,保障安装的顺利进行。以荔湾3-1浮托安装为例,讨论了浮托安装过程中用到的实测技术,主要包括:浮托驳船及组块插尖的六自由度运动监测;施工海域海洋气象条件监测——风、浪、表面流和潮位;浮托驳船两侧护舷的载荷监测。并通过对实测结果进行综合分析,给出可靠的实测数据,为对比理论计算和模型试验,检验预报方法的可靠性提供支持。 相似文献
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海洋石油工程具有高投资、高风险、高技术含量等特点.海洋石油工程是项复杂的系统工程,提高服务管理水平,对于保证施工、建造、拖航及安装设置过程的安全,提高效率,进而提高竞争力极为重要.文中提出了海洋石油工程服务管理的系列理论与方法,并提出海洋石油工程服务管理中应注意的事项,为此类工程项目管理提供合理建议. 相似文献
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海底管线调查综合物探作业方法研究 总被引：2，自引：0，他引：2
海底石油管线调查方法包括物探方法和潜水方法或两者的结合。综合物探作业方法是综合利用浅地层剖面、旁侧声纳、测深仪、磁力仪等手段探测和分析海底管线状态。文章给出各种物探手段联合作业方法、作业程序和注意事项,以及数据处理方法;对布线方法、仪器选择原则及作业关键点进行较详细的说明,对海底管线综合物探作业给与了指导。 相似文献