用分段定向钻进方法铺设弧形轨迹集束管

横穿开洛高速公路６５．４ｍ,贯通９个收费亭人井,１１段路基,按路面形状成中间高,两端低的菜钻孔;多级扩孔至孔径５００ｍｍ,在其中铺设Х１１４ｍｍ钢管４根,Х６０ｍｍ钢管３根。两组这样的管束平行间距始终保持４５０ｍｍ,按轨迹设计要求,准确无误的到达出口。     

Physics of Atoll Groundwater Flow

Large-scale steady-state groundwater flow in atoll carbonate platforms results from temperature and salinity-induced density gradients. Atolls are built on top of a basaltic substrate that provides geothermal heating from beneath. Moreover, they are immersed in the tropical ocean where temperature decreases rapidly with depth. Groundwater circulation in these platforms has long been associated with the geothermal heat flux because it is capable of generating inward and upward flow of oceanic origin water by buoyancy effects. This study shows that hydraulic circulation occurs even in the absence of a geothermal flux because the combination of the cold subsurface ocean waters with the warm surface conditions is sufficient to maintain a convection cell within the carbonate platform. Using a one-dimensional analytical model, validated by more sophisticated two-dimensional simulations, we can investigate the interaction between these two driving forces. The flow rate inside the platform is, in fact, a function of the ratio of the geothermal flux to the temperature gradient in the ocean. It increases with the geothermal flux but decreases with the oceanic temperature gradient. This one-dimensional model also shows that taking salinity effects on density into account increases the flow rates transiting through the platform by a third.     

干旱缺水地区深水井泡沫钻进技术研究

依据泡沫的优点 ,提出了在干旱缺水地区采用深水井泡沫钻进技术的钻探新方法。给出了深水井各孔段的成孔工艺 ,重点阐述了深水井泡沫钻探灌注系统的主要设备和泡沫钻进工艺的规程参数 ,并指出采用该技术可解决在干旱缺水地区施工 5 0 0～ 80 0m深水井的问题。     

多筒吸力平台沉放调平模型试验

描述了位于渤海辽东湾93地区人工岛靠船系缆平台沉放调平模型的试验过程,系缆平台的基础采用了三筒结构型式,这也是我国应用于海洋工程的第一个多筒型基础平台,尽管海上施工前对筒型基础沉放已有了一定的经验, 但多数都是基于吸力锚或单筒式吸力平台结构,对于多筒式吸力基础平台还没有任何的工程经验。试验为海上原型结构沉放施工可行性及施工调平程序的编制起到了一定的指导作用。     

台网系统监视平台

广东数字遥测地震台网的台网系统监视平台,是为监视台网中心的运行和台站仪器状况而设计的,通过网络对实时地震数据收集、处理系统运行和台站状态进行图形化自动监视,当发生地震事件、断记或系统故障时该平台能自动报警。实践表明,它既减轻了监测值班人员的工作负担,又为仪器维修人员跟踪台站仪器故障提供了帮助。     

漏磁无损检测在科学钻探钻柱损伤监测中的应用前景

通过调研分析国内外漏磁无损检测技术在钻井中的应用现状,结合科学钻探钻柱结构及损伤特点,探讨漏磁无损检测技术在科学钻探钻柱损伤检测中的应用前景。     

非开挖铺管技术在开封-洛阳高速公路郑州东段中的应用

介绍了河南开封至洛阳高速公路郑州东段非开挖铺设电力电讯管道的施工工程,包括设备选择,施工工艺、施工中遇到的问题以及解决这些问题的办法。     

Optimal Design of TMD Under Long-Term Nonstationary Wave Loading

—Traditionally,the use of a tuned mass damper(TMD)is to improve the surviability of the pri-mary structure under extraordinary loading environment while the design loading condition is describedby either a harmonic function or a stationary random process that can be fully characterized by a powerspectral density(PSD)function.Aiming at prolonging the fatigue life of an offshore platform,this studyconsiders an optimal design of TMD for the platform under long-term nonstationary loading due tolong-term random sea waves characterized by a probabilistic power spectral density(PPSD)function.Inprinciple,a PPSD could be derived based on numerous ordinary PSD functions;and each of them is treat-ed as realization of the corresponding PPSD.This study provides a theoretical development for theoptimal TMD design by minimizing the cost function to be the mean square value of the expectedlong-term response.A numerical example is presented to illustrate the developed design procedure.     

Optimum Design of Structure Shape for Offshore Jacket Platforms

With the introduction of the design variables of nodal coordinates,which reflect the em-bedded depth of the pile and the jacket bed height,a shape optimum design model for offshore jacket plat-forms is established.A sequential two-level optimum algorithm is developed based on the design variablegradation.On the basis of the finite element method,the sensitivity of the objective function and nodal dis-placement is analyzed.As an example,the BZ281 oil storage offshore platform,which lies in the Bohai oilfield,is designed with the shape optimum model.The results are compared with the cross-section optimumdesign.The tendency of design variables and its reasons in the two methods are analyzed.In the shapeoptimum design,the value of objective function is obviously smaller than that of the initial design and thecross-section optimum design.Therefore,the advantage of structure shape optimum design for jacket plat-forms is remarkable.     

确定海洋平台钢裂纹扩展曲线的快速方法

提出了一种确定海洋平台钢裂纹扩展曲线的快速方法。该方法可以综合利用以往的经验数据和当前试验数据确定表面疲劳裂纹扩展速率曲线。与传统的只能利用当前试验数据确定表面疲劳裂纹扩展速率曲线相比。其可利用信息量大幅度增加,所以在精度相同的情况下,可以节省大量试件;而且在试样数一定的情况下。又可大大提高预测精度。文中还给出了海洋平台钢试验对比实例。