Marine tether dynamics: retrieval and deployment from a heaving platform     

R. E. Baddour  W. Raman-Nair 《Ocean Engineering》2002,29(13):550-1661

A tether management system of a winch module in a marine environment is proposed. For the purpose of this study the subsea body is considered as a mass attached at the free end of a long tether which is wrapped around a circular drum controlled by an external torque. The winch is considered mounted on a heaving platform. The effect of the heaving platform on the motions of the drum, tether and attached mass are studied with respect to the longitudinal vibrations of the tether in one dimension. The hydrodynamic effects are considered on the deployed portion of the tether and the tethered mass, both of which are assumed submerged in otherwise still water. The resulting nonlinear system of equations of motion is developed and solved numerically for an example of a marine tether system. The effect of the tether extensibility on the operation threshold of the system is identified. Comparison with an inextensible tether case is provided. The numerical results and their analysis for the retrieval/deployment of the system are presented.  相似文献   

Simulation of Pollutant Transport in Marmaris Bay     

Lale BALAS 《中国海洋工程》2001,(4):565-578

The circulation pattern and the pollutant transport in the Marmaris Bay are simulated by the developed three-dimensional baroclinic model. The Marmaris Bay is located at the Mediterranean Sea coast of Turkey. Since the sp ring tidal range is typically 20- 30 cm, the dominant forcing for the circulation and water exchange is due to the wind action. In the Marmaris Bay, there is sea outfall discharging directly into the bay. and that threats the bay water quality significantly. The current patterns in the vicinity of the outfall have been observed by tracking drogues which are moved by currents at different water depths. In the simulations of pollutant transport, the coliforms-counts is used as the tracer. The model provides realistic predictions for the circulation and pollutant transport in the Marmaris Bay. The transport model component predictions well agree with the results of a laboratory model study.  相似文献   

GPS技术在山区石油地震勘探测量中的应用     

刘兵  施昆  韦瑞表  缪祥柱 《测绘工程》2008,17(6):63-66

针对GPS技术在山区石油地震勘探测量中的工作方式,结合2007年度南盘江一桂中地区二维地震大剖面资料采集应用GPS的工程实例,介绍GPS技术应用的新进展。通过GPS静态测量和应用RTK技术放样物理点,从测前准备、数据处理、精度分析等方面,阐述提高作业精度、有效进行质量控制的方法,旨在最大限度地发挥GPS技术在山区施工中的作用。  相似文献   

Break out resistance of inclined anchors in sand     

Shubhra Goel  Shalini  Nihar Ranjan Patra 《Geotechnical and Geological Engineering》2006,24(6):1511-1525

Inclined anchors are widely used in a variety of civil engineering problems to resist oblique loads, most relevant being in transmission towers and in rocks and dams for structural strengthening. In the present study, the breakout resistance of the inclined anchors in sand has been worked out using limit equilibrium approach. The breakout resistance has been calculated for different soil friction angles with varying relative depth ratio and anchor inclination. The break out factor increases continuously with the inclination of the anchor. A comparison of predicted values of break out resistance of anchors by the proposed analysis with the experimental values as reported by the other researchers showed reasonably good agreement.  相似文献   

注浆、抽水、掏土法在建筑物纠偏加固中的应用     

陈宏杰  陈昌友 《中国煤田地质》2003,15(2):47-48

针对因地基条件复杂或处理不当引起地基不均匀沉降而造成的建筑物倾斜,提出了注浆、抽水、掏土法,对建筑物进行纠偏加固处理,取得了良好的经济效益和社会效益。  相似文献   

GPS-RTK在小城市测量中的应用   总被引：14，自引：0，他引：14  

江金霞  江丽钧 《华东地质学院学报》2003,26(4):394-396

叙述了GPS-RTK测量在浙江省丽水市城市首级控制、基本控制、地形测图、施工放样的运用，并且与传统作业方法作了简明扼要的比较，提出了在GPS-RTK运用过程中的一些可行方法。  相似文献   

抽放瓦斯定向钻孔施工技术的研究   总被引：3，自引：0，他引：3  

郝世俊 《探矿工程》2003,30(4):50-52

介绍了抽放瓦斯定向钻孔施工技术的主要设备、钻具及仪器，组合钻具及钻进工艺参数，并通过几个工程实例，说明了该项技术的应用效果。  相似文献   

高层建筑中轴线点恢复测量     

欧海平  林鸿 《测绘与空间地理信息》2003,26(2):18-19

高层建筑物中点恢复的测量方法是在负一层测定该建筑物的中点,再引到四层楼顶,最后重新确定施工放样数据,保证该建筑物的设计要求和施工监测。  相似文献   

煤矿采空区场地建筑适宜性工程地质研究方法   总被引：5，自引：0，他引：5  

马金荣  彭向峰 《煤田地质与勘探》1996,24(6):44-46

简述了煤矿采空区场地存在的工程地质问题；提出了查明采空区场地工程地质条件的现场勘察和室内模拟研究方法。并结合采空区活化特点，对采空区场地建筑适宜性作了分析；提出了地基处理和建筑物防护措施  相似文献   

后方交会法配合可编程计算器在测量放线中的应用     

廖志平 《中国煤田地质》2004,16(1):60-61

介绍了后方交会及支导线的计算方法，探讨了Casio Fx4500计算器程序的编制，说明后方交会法配合可编程计算程序在道路施工及其它测量放线过程中不仅克服了其路基不平等许多不便之处，而且大大提高了测量放线的速度和精度，值得推广应用。  相似文献