Inclined loading capacity of suction piles in sand

A series of centrifuge model tests have been conducted on a model suction pile embedded in sand to evaluate its inclined pull-out loading capacity. This paper describes the centrifuge model tests, the analytical solution, and comparisons between the centrifuge model test results and the analytical predictions of the pull-out capacities of the suction pile under inclined loads. The main variables of the study are the load inclination angle and the point of mooring line attachment which varies from the top to the bottom of the suction pile’s side surface. Effects of these two parameters on the suction pile inclined pull-out loading capacity are described.     

Vertical exaggeration of reflection seismic data in geoscience publications 2006-2010

Reflection seismic data is widely-used in industry and academia. It is often interpreted and displayed with considerable vertical exaggeration. Vertical exaggeration is defined as the vertical to horizontal aspect ratio of a reflection seismic cross section in depth. Recent literature is reviewed here to quantify for the first time the extent and typical values of vertical exaggeration in published work. Results are collated from 1437 papers published in 68 journals in the period 2006-2010. This broad scope is intended to provide a global view but it does not claim to be exhaustive. One example from each paper was analysed. Depth conversion was necessary in 74% of cases (every case of time-domain seismic with vertical exaggeration not stated). The main findings are that only 12% of papers use aspect ratios with vertical scale set approximately equal to horizontal scale (vertical exaggeration in the range 0.8-1.2). 75% of papers use reflection seismic with vertical exaggeration greater than 2. Splits of the data in terms of shallow high resolution seismic and deep, crustal imaging seismic were also obtained. The cause of this very widespread vertical exaggeration of reflection seismic cross sections is generally some form of display optimisation, such as emphasis of stratigraphic architectures or displaying long sections that would otherwise not fit on screen, or effects related to seismic sampling, but a specific reason is rarely stated. Angular relationships in stratigraphic and structural architectures are distorted so commonly that true geometries are rarely seen, which becomes an issue if readers are unfamiliar with these geometries. There is a clear opportunity for authors who display and publish reflection seismic data to annotate an estimate of vertical exaggeration alongside other standard annotation on seismic displays.     

1999—2018年锦州地区大雾气候特征及成因分析

应用常规气象观测资料、能见度仪观测资料,分析1999—2018年锦州地区大雾气候特征及成因。结果表明：锦州地区雾日年总频次多年平均为33次,存在12 a、6 a和3 a的变化周期。锦州地区典型大雾过程主要分为弱低压槽型、雨后弱高压型。大雾存在日变化。雾前T-T_d为4—14℃,风速为4 m·s^-1以下,偏南风占50%,偏北风占38%,静风占12%;雾发展阶段T-T_d为0—4℃,平均风速为2.2 m·s^-1,偏南风占58%,偏北风占42%;浓雾阶段T-T_d为0—2℃,平均风速为1.9 m·s^-1,偏南风占58%,偏北风占42%;雾减弱到消散阶段T-T_d逐渐升高,平均风速为3.3 m·s^-1,偏北风占58%。大雾期间,均出现逆温和湿层。     

提取垂直形变信息时富氏系数及其阶数的合理选取

用富里叶分析提取垂直形变信息,是值得进一步研究的课题。本文主要讨论了两个问题:1)采样点间距与可能得到的富氏系数的最高阶数;2)如何获取合理的富氏系数。     

优化反演方法及数值反演试验初步研究

基于典型力学模型。以研究区域的岩性参数和研究块体的边界力作为反演参数进行数值模拟，研究了单纯形法，模式搜索法，鲍威尔法，变量轮换法，混合罚函数法，复合形法等6种最优化反演方法的反演效果和可靠性。结果显示6种方法都有较好的表现。在恰当的条件下，6种方法反演所得参数都达到或接近参数的理论值，迭代收敛图，位移拟合曲线和残差统计分布图直观地反映出6种方法的效果和可靠性，但对单纯形法和复合形法应给予较高的迭代收敛精度。     

GPS测量揭示的福建沿海地区的现今地形变

根据福建GPS监测网3期(1997，1999，2001)观测资料的计算结果，分析了福建沿海地区的现今地形变特征。(1)福建地区有两个剪应变相对集中区，北部是湾口、闽清一带；南部是泉州、厦门一带。这两个区的剪应变随时间变化有加强的趋势。(2)南部剪应变集中区基本处于压应变环境，并且主要断裂两侧存在相对较高的剪应变集中区，值得关注。     

基桩承载特性的位移协调法分析研究

介绍了利用位移协调法分析基桩承载特性的理论基础及计算方法。根据郑州某工程的静载试验资料,求得桩身荷载的传递函数,并利用该函数对基桩承载特性进行了分析。得出了可利用实测传递函数对同一场地的不同桩长、桩径或具有相同工程地质条件的不同场地的基桩进行承载特性分析的结论,以及桩端土层的力学指标和桩身弹模的选取对计算结果有较大影响的结论。     

液体-固体分界面处斯通利波的波速方程

推导出液体—固体分界面处斯通利波波速方程的几种不同表达式,并对结果进行了简单讨论。     

鲁西尚河韧性剪切带变形特征研究

发育于鲁西隆起区尼山凸起内的尚河韧性剪切带,其韧性变形在不同阶段主导变形机制不同:初期的变形机制以晶格错位和显微破裂为主;中期以韧性流动、物质扩散迁移为主;晚期以晶质塑性变形和颗粒边界滑动为主。在剪切带的发育过程中,岩石的物质成分和体积都发生了较大变化。根据构造岩的矿物组合和形变特征判断,该剪切带具右行走滑性质,其剪切位移量为1048m。尚河韧性剪切带变质变形温度较低,属绿片岩相动力变质作用。