深水平台吸力沉箱基础工程地质问题分析

针对深水平台吸力沉箱基础,讨论了与沉箱安装有关的分析方法及涉及的工程地质参数,分析了承受竖向拉拔荷载、倾斜与水平荷载作用的吸力沉箱极限承载力的分析方法及涉及的工程地质参数,对与吸力沉箱设计有关的其它问题也进行了分析.在此基础上,阐明了与吸力沉箱设计有关的工程场地调查内容及需要确定的工程地质参数.其目的是为开发深水平台吸...     

青岛即墨月亮湾岸滩开发利用与岸线整治保护工程方案分析

从整治工程区海域由于受潮流、波浪影响侵蚀和严重蚀退的海岸线,防治现状岸线入手,对工程区域的工程环境进行了综合研究,对岸滩开发利用整治与岸线保护工程方案进行了比选分析.结果表明,该工程区域采用斜坡堤护岸结构形式对岸线进行保护是较合理的.这样,可以对优化工程环境,保护当地的海洋岸线,防治岸线蚀退,美化岸滩自然环境取得更好的...     

多源地图数据出版的探讨

当前多源地图数据的非共享性等特点严重制约了地图数字出版流程的顺利开展。为了有效解决多源地图数据到印前数据的转换问题,根据多源地图数据的类型及特点,结合出版对地图数据的特殊要求,建立并实现了一套完整的由多源地图数据转换为印前数据的方案,并通过具体应用得到有效的验证。     

Parametric vibration of submerged floating tunnel tether under random excitation

For the study of the parametric vibration response of submerged floating tunnel tether under random excitation,a nonlinear random parametric vibration equation of coupled tether and tube of submerged floating tunnel is set up.Subsequently,vibration response of tether in the tether-tube system is analyzed by Monte Carlo method.It may be concluded that when the tube is subjected to zero-mean Gaussian white noise random excitation,the displacement and velocity root mean square responses of tether reach the peak if the circular frequency of tube doubles that of tether;the displacement and velocity root mean square responses of tether increase as the random excitation root mean square increases;owing to the damping force of water,the displacement and velocity root mean square responses of tether decrease rapidly compared with tether in air;increasing the damping of the tether or tube reduces the displacement and velocity root mean square responses of tether;the large-amplitude vibration of tether may be avoided by locating dampers on the tether or tube.     

The status of geological dredging techniques

Scientific sea-floor dredging is currently used in marine geology primarily by the hard-rock community interested in the recovery of basement rock samples from the unsedimented deep ocean floor. The technique has generally been eclipsed by ocean drilling for recovery of sedimentary rocks, because of perceived uncertainties in the location of sampling and in the representativeness of recovered material. This contribution reviews dredging equipment currently in use by marine geological institutions and refers to pinger attachments that allow precise information on the behaviour of the dredge to be telemetered back to the ship. We argue that improvements in ship navigation and transponder navigation at the seafloor, when used in conjunction with surface and/or deeply towed sidescan and swathemapping surveys, now allow for considerably less uncertainty on the location of dredge sampling. Refined sorting criteria for dredge hauls are now also available. Recent comparisons of regional sample recovery by ocean drilling and by dredge sampling indicate that the dredge hauls can usefully supplement the drilling data in the construction of sedimentary and tectonic histories of seafloor areas.     

河南省黄河流域黄土的发育特征及其古气候环境分析

为防治黄土土壤侵蚀和治理黄河,本文根据磁性地层学、年代地层学(热释光法),并结合岩石地层学,生物地层学和气候地层学等方法,对河南省黄河流域广泛分布的陆沉积黄土进行分析。将区内黄土划分为上更新统黄土(Q3^eol)、中更新统黄土(Q2^eol)、下更新统黄土(Q1^eol)。研究结果表明,不同时期的黄土,其岩性、结构、古地磁特性以及古土壤层数等有明显的差异。此外,不同时期黄土所含的值物孢粉组合特征亦不相同,从而反映了更新世冷暖交替的古气候环境特征。     

土壤渗滤处理技术在海岛生活污水处理中的应用

土壤渗滤处理系统设备简单、投资少、操作管理方便、能耗低,净化效果良好,在处理海岛生活污水领域具有广阔的发展前景.根据鼓浪屿目前污水水质、水量的特点,采用土壤渗滤高度水处理技术对污水进行处理,污染物经过土壤的物理、化学和生物作用,出水达到《城市污水再生利用城市杂用水水质》(GB/T18920-2002),具有不产生污泥,运行简单,氮磷去除效率高,无二次污染等特点.     

东海油气资源区海底沉积物的工程地质特征

根据2001年6月的航次调查及随后的沉积物样品的试验室分析资料,从物理性质和力学特征各方面对东海油气资源区海底沉积物进行了综合工程地质特征研完。发现本区沉积物结构、剪切特征、含水量和液塑限随深度的变化而变化;本区海底沉积物类型既分布有中砂、细砂和粉砂3种砂性土,也分布有扮质粘土、淤泥质粘土和粘质扮土3种粘性土,沉积物的物理力学性质与相立的土类性质相一致。     

Spectral Analysis of Nonlinear Drag Forces

The spectral properties of nonlinear drag forces of random waves on vertical circular cylinders are analyzed in this paper by means of nonlinear spectral analysis. The analysis provides basic parameters for estimation of the characteristic drag forces. Numerical computation is also performed for the investigation of the effects of nonlinearity of the drag forces.The results indicate that the wave drag forces calculated by linear wave theory are larger than those calculated by the third order Stokes wave theory for given waves. The difference between them increases with wave height. The wave drag forces calculated by use of hnear approximation are about 5% smaller than their actual values when measured in the peak values of spectral densities. This will result in a safety problem for the design of offshore structures. Therefore, the nonlinear effect of wave drag forces should be taken into comidemtion in design and application of important offshore structures.     

基于圆特征的地图要素自动综合算法研究

分析了目前地图综合的地位、作用和发展情况,介绍了“优胜劣汰”思想,分析对比出自然界“优胜劣汰”基本思想和地图制图综合在某些方面存在共同的相似之处,从而尝试把它运用到地图制图综合中来,并结合Circle技术及其基本特点,提出了基于Circle原理和“优胜劣汰”思想的地图综合新算法,在地图综合的选取、化简、合并等方面得到了较好的应用,相应的例子在文中详细地进行了列举。