交互的初至波反演及静校正

一种人机交互式的初至波反演方法是在反演过程中加入人为的干预,并利用人的经验控制反演的方向,使结果更加符合实际的地质情况。再将反演的结果与其它的短波长静校正方法相结合,就能够有效地提高静校正的精度。实例证明,这种方法是有效且可行的。     

迭代折射静校正技术在鄂北地震资料处理中的应用

在低速层速度(地表直达波)已知的条件下,利用生产炮初至信息,用加权最小平方法和共轭梯度法建立的折射静校正数学模型,迭代求取长波长、短波长静校正量,在解决鄂尔多斯盆地北部的虚假小幅度构造问题及改善剖面质量方面取得了明显的效果。     

World-wide synthetic tide parameters for gravity and vertical and horizontal displacements

The response of the Earth’s crust to the direct effect of lunisolar gravitational forcing is known as the body tide. The body tide is superimposed by surface-loading forces due to the pressure of the periodically varying ocean tide acting on the Earth, called ocean tide loading (OTL). Both body tide and OTL can be decomposed into components of the same frequency known as tidal parameters. However, OTL is more complicated than body tides because of the dynamic effects of the ocean. Estimating OTL requires a model of the ocean tides and knowledge of the elastic properties of the solid Earth. Thus, synthetic tide parameters (amplitude factors and phase leads) have been developed here on a world-wide grid for gravity and positional displacements. The body tide contributions were added to the oceanic contribution to provide the Earth tide response. The accuracy and reliability of the synthetic tidal parameters have been estimated by comparing observed gravity and vertical-displacement tide parameters with those interpolated from our synthetic model, which shows good agreement. Tests also indicate that the synthetic tide parameters provide realistic gravimetric and displacements for practical use in tidal prediction.     

三峡库区滑坡治理工程设计中推力荷载计算方法初探

随着三峡水利工程的逐步实施，淹没区移民及新城镇建设等人类工程活动的加剧，以滑坡为主的环境地质问题日益突出。本文从稳定系数、安全系数入手，对铁道、公路等部门常用的设计计算原理进行了研究，并由此类比分析研究了三峡区回水后或库水位正常运行条件下，滑坡治理工程设计计算方法。     

Damaging properties of ground motions and prediction of maximum response of structures based on momentary energy response

Dynamic damaging potential of ground motions must be evaluated by the response behaviour of structures, and it is necessary to indicate what properties of ground motions are most appropriate for evaluation. For that purpose, the behaviour of energy input process and hysteretic energy dissipation are investigated in this study. It is found that the momentary input energy that is an index for the intensity of input energy is related to the characteristics of earthquakes such as cyclic or impulsive, and to the response displacement of structures immediately. On the basis of these results, a procedure is proposed to predict inelastic response displacement of structures by corresponding earthquake input energy to structural dissipated damping and hysteretic energy. In this procedure the earthquake response of structures is recognized as an input and dissipation process of energy, and therefore structural properties and damaging properties of ground motions can be taken into account more generally. Lastly, the studies of the pseudodynamic loading test of reinforced concrete structure specimens subjected to ground motions with different time duration are shown. The purpose of this test is to estimate the damaging properties of ground motions and the accuracy of the proposed prediction procedure. Copyright © 2002 John Wiley & Sons, Ltd.     

Static deformation of two welded monoclinic elastic half-spaces due to a long inclined strike-slip fault

Static deformation of two monoclinic elastic half-spaces in welded contact due to a long inclined strike-slip fault situated in one of the half-spaces is studied analytically and numerically. Closed-form algebraic expressions for the displacement at any point of the medium are obtained. The variation of the displacement at the interface with the horizontal distance from the fault is studied. The effect of anisotropy on the displacement field is examined. It is found that while the anisotropy of the source half-space has a significant effect on the displacement at the interface, the anisotropy of the other half-space has only a marginal effect.     

三原井水位固体潮加卸载响应比的地震异常

讨论了三原井水位在泾阳4．8级地震前的变化特征，重点是泾阳地震前水位对固体潮响应的变化，即固体潮加卸载响应率与加卸载响应比的变化，对水位观测资料的计算分析表明，震前加卸载响应率及响应比有“平稳－升高－恢复”的特征，说明水位固体潮加卸载响应比方法有可能捕捉5级左右近震的前兆信息。     

Transient foundation solution of saturated soil to impulsive concentrated loading

The transient dynamic response of saturated soil under suddenly applied normal and horizontal concentrated loading is studied in this paper. The behavior of saturated soil is governed by Biot's consolidation theory. The general solutions for Biot equations of equilibrium are derived in terms of displacements and variations of fluid volume, using Laplace–Hankel integral transforms. The solutions in the time domain can be evaluated by numerical inverse Laplace–Hankel transforms. Selected numerical results for displacements, stresses, and pore pressures are presented. Comparisons with existing closed-form solutions for the elastic half-space are made to confirm the accuracy of the present solutions. The solutions can be used to study a variety of transient wave propagation problems and dynamical interactions between saturated soil and structures.     

饱和岩石的各向异性及非线性黏弹性响应

在MTS伺服压机上对不同饱和状态的砂岩、大理岩标本进行了垂直层理和平行层理两个方向的正弦波加载试验,研究了饱和岩石的各向异性及非线性黏弹性行为. 在最大载荷低于岩石的屈服点时,获得的衰减、杨氏模量、泊松比、波速都表现出显著的各向异性,同时它们还具有较明显的应变振幅效应和频率效应. 随着应变振幅的增大,衰减近似呈线性增长,杨氏模量和泊松比近似呈线性下降. 在0.005-4Hz频段内除衰减不明显依赖频率以外,杨氏模量、泊松比、波速对频率的依赖性都较强; 当频段扩大到15Hz时,这4个参数都表现出较强的频率效应. 饱和岩石的衰减、杨氏模量、泊松比、波速均随饱和液体的黏滞系数增大而增大.     

铅橡胶复合阻尼器的性能试验研究

介绍作者提出的铅橡胶复合阻尼器的构造与耗能原理，通过不同形状，不同大小铅心的8个铅橡胶复合阻尼器的循环荷载试验，研究了频率、应变幅值、循环次数、铅芯直径、竖向压力等对铅橡胶复合阻尼器的影响规律。研究结果表明，铅橡胶复合阻尼器工作性能稳定，耗能性能和抗疲劳性能好。