地基土地震液化评价方法探讨

本文对现行的“抗震设计规范”中有关地震液化评价条文进行了探讨,提出了以单元体及场地土作为评价单元,尝试引出了判别指标”场地单元体液化指数 A”。另外,对在评价过程中遇到的几个问题进行了讨论,如:贯入击数基准值的选用,软夹层的处理等。     

Gauss-Helmert模型及其在测量平差中的应用

对于Gauss-Helmert模型,本文直接从广义逆阵的性质而不必通过Lagrange乘子方法简洁地给出参数向量的最佳线性无偏估计(BLUE),然后将所得结果用于求解测量平差中的拟合推估问题,以及广义的含未知量的带权条件平差问题。     

以电阻率测量资料为基础评价珙县磷铵厂建筑场地条件

本文根据在珙县磷铵厂建筑场地视电阻率测量的结果,将场地分为三个区,并结合钻探触探结果对各区的工程地质条件、邻区地震的影响等进行了具体的评价。给该厂的建筑设计提供了较确切的依据,改变了原建筑布局方案,收到了较好的效果。     

对高美古选址云量观测可靠性的讨论

通过对新月和满月夜期间测光夜数和云量统计数的比较, 高美古的天文测光夜数和可用夜数与丽江县的气象晴日数的比较, 以及在同样的观测时间高美古和丽江县云量观测值的比较, 本文对高美古选址云量观测可靠性的有关方面进行了讨论     

陕西临潼零口文化遗址脊椎动物遗骸的古环境意义

陕西省临潼零口遗址脊椎动物遗骸有Rhizomys sinensis,Hystrix hodgsoni,Nyctereutes procyonoides,Meles meles,moschus sp.,Ceruvs hortulorum,Elaphurus davidianus,Caprinae,Gazella sp.,Bovinae,Sus domesticus,Phasianidae和Cyprinoid，可分为5层位，其年代为7300aBP 380-6220aBP 407和仰韶西王村类型。动物生态、动物地理及其他气候替代性指标显示了零口文化和仰韶文化的1500年间包含了2个相连续、但不完整的气候演变周期。每个气候演化延续时间约为700－800a。气候演化周期与文化发展周期基本吻合。     

关于场地液化评价的几点认识

较详细地分析说明了土层埋深、地下水位对临界标贯击数的影响，澄清了规范公式所带来的上覆应力增加会使土层更易液化的误解。在对规范液化指数分析基础上，重新定义了液化指数。新定义的修正液化指数概念具有明确的概率意义，适用于场地液化评价和风险决策。     

Fast spherical collocation: theory and examples

 It has long been known that a spherical harmonic analysis of gridded (and noisy) data on a sphere (with uniform error for a fixed latitude) gives rise to simple systems of equations. This idea has been generalized for the method of least-squares collocation, when using an isotropic covariance function or reproducing kernel. The data only need to be at the same altitude and of the same kind for each latitude. This permits, for example, the combination of gravity data at the surface of the Earth and data at satellite altitude, when the orbit is circular. Suppose that data are associated with the points of a grid with N values in latitude and M values in longitude. The latitudes do not need to be spaced uniformly. Also suppose that it is required to determine the spherical harmonic coefficients to a maximal degree and order K. Then the method will require that we solve K systems of equations each having a symmetric positive definite matrix of only N × N. Results of simulation studies using the method are described. Received: 18 October 2001 / Accepted: 4 October 2002 Correspondence to: F. Sansò