Geoid Determination through Ellipsoidal Stokes Boundary-Value Problem

Martinec and Grafarend (1997) have shown how the construction of Green's function in the Stokes boundary-value problem with gravity data distributed on an ellipsoid of revolution is approached in the O(e ₀ ² )-approximation. They have also expressed the ellipsoidal Stokes function describing the effect of ellipticity of the boundary as a finite sum of elementary functions. We present an effective method of avoiding the singularity of spherical and the ellipsoidal Stokes functions, and also an analytical expression for the ellipsoidal Stokes integral around the computational point suitable for numerical solution. We give the numerical results of solving the ellipsoidal Stokes boundary-value problem and their difference with respect to the spherical Stoke boundary-value problem.     

Contribution of Local Seismic Networks To The Regional Velocity Model of The Bohemian Massif

The routine location of regional seismic events using data from the Czech National Seismological Network (CNSN) is based on Pn, Pg, Sn, Sg phases. A simple velocity model derived from Kárník's (1953) interpretation of an earthquake in Northern Hungary in 1951 has hitherto been used. At present, numerous local seismic networks record and locate local events, which are occasionally recorded at regional distances as well. Due to the relatively small dimensions of local networks, hypocenters (and origin times) determined by a local network might be considered as nearly exact from the point of view of regional-scale CNSN. The comparison of common locations performed by CNSN and by a local network enables us to estimate the accuracy of CNSN locations, as well as to optimize a simple velocity model. The joint interpretation of the CNSN bulletin and the catalogues of four local seismic networks WEBNET, OSTRAVA, KLADNO and LUBIN produced a new ID velocity model. The most frequent epicentral error in this model is less than 5 km, and most foci lie up to 15 km from the true position. The performed analysis indicates bimodal distribution of Sn residuals.     

水泥土深层搅拌桩在长江堤防管涌险段治理工程中的应用

本文通过一工程实例介绍水泥土深层搅拌桩技术在治理长江堤防管涌险段工程中的设计原则和施工,检测方法及应该注意的问题。     

垃圾夯扩短桩在邯郸市的工程实践

本文阐述垃圾夯扩短桩在邯郸新近堆积软土场地上的工程尝试,分析了其加固地基的机理,结合工程实例论述了夯扩短桩在邯郸的适应性及其推广应用前景。     

建筑桩基的有效应力地震反应分析：Ⅰ--计算方法

根据地震作用、上部结构、桩基的特点,建立了建筑桩基地震反应分析的计算模型,考虑了桩-土-上部结构的动力相互作用。然后将饱和土体视为由固、液二相组成的两相介质,基于Biot动力固结方程,提出一种建筑桩基地震反应的有效应力动力分析方法,并给出了具体计算步骤。     

桩基负摩阻力在纠倾工程中的应用

:分析探讨了桩基负摩阻力的特性 ,提出了桩基下拉荷载的经验公式 ,并通过某深桩基础的纠倾工程验证了所建议公式的可行性 ,为桩基负摩阻力在建筑物纠倾工程中的应用提供了理论依据 ,为深桩基础建筑物的纠倾扶正技术提供了一种行之有效的方法     

摩擦桩沉降变形规律及承载力确定的探讨

在现场的桩基垂直静载荷试验基础上 ,进行荷载传递机理分析和沉降变形的阶段性划分 ,探讨了确定单桩竖向承载力的新方法 ,为工程合理、充分地利用承载力提供参考。     

地电化学参数法在金矿深部定位预测中的应用

介绍了地电化学参数法的基本原理和工作方法 ,通过在不同地区、不同金矿类型中进行的试验和应用结果表明 ,与其它一系列寻找隐伏矿的方法相比 ,该方法在寻找隐伏矿体方面具有快速、有效、低成本、高精度的特点。     

横向土运动作用下群桩的性状研究

以有限元与有限差分相结合,对横向土运动作用下的群桩工作性状,产生群桩效应的临界桩距、桩数及排列、桩顶边界条件等影响因素作出分析;并对沿桩排的应力分布作出初步探讨。     

高层建筑夯扩短桩桩筏基础沉降计算模式研究

根据高层建筑夯扩短桩桩筏基础的受力机理,建立了一套计算该基础沉降的模型,并利用3个工程实例对该模型进行了验证。