Simulation of Ground Motion at Guanting Reservoir Dam Based on the Scenario Earthquake in the Yanqing-Huailai Basin

Research at home and abroad shows that the simulation of ground motion using the 3D finite-difference method might be accurate and feasible. Based on related theories and methods,and using the wave velocity and density model of the crust in the Yanqing-Huailai Basin,this paper makes a simulation of ground motion at Guanting Reservoir Dam based on the scenario earthquake in the Yanqing-Huailai Basin. Comparative analysis shows that the results of 3D finite-difference simulation accord with those of the empirical formula. The parameters such as the velocity-time series of ground motion,PGV and frequency might be referred to for the analysis of seismic protection design of the dam's structure.     

Optimization tools and simulation methods for designing and evaluating a mining operation

Some of the major advances in the field of mining in the last three decades have referred to the development of new design and planning techniques for optimizing open-pit mining and the inclusion of a stochastic perspective in economic models that is more revealing than a purely deterministic perspective. These advances include the use of parametric techniques in the design and planning process, the formulation of criteria for establishing an optimum cut-off grade policy when the economic goal is to optimize net present value (NPV), and the introduction of economic risk analysis. This paper examines some of the difficulties involved in applying these techniques—arising largely as a result of a lack of knowledge of the spatial location and distribution of the deposit grades—and analyses how these difficulties can be tackled with the help of geostatistical simulation techniques that take probabilistic criteria into consideration during the optimization process. These techniques enable equally likely representations of the deposit to be obtained that reproduce the main dispersion features for the starting experimental data (covariance or variogram, as well as the histogram). Consequently, the uncertainty in regard to the deposit as well as its influence on the economic assessment of the deposit in risk terms can be evaluated. This paper also describes a simple method for introducing price and cost increases into the risk analysis via the Monte Carlo method and shows how geological, technical and economic uncertainty can be integrated in risk analyses. Although it is true that the relationship between prices and costs is maintained constant in mining planning based on using parametric techniques, it is no less true that the risk analysis requires the use of models in which the main parameters with a bearing on deposit economics are considered as stochastic variables. The proposed methodology simplifies the calculations and easily integrates the different sources of uncertainty.

An integrated fuzzy-stochastic modeling approach for assessing health-impact risk from air pollution

High concentrations of air pollutants in the ambient environment can result in breathing problems with human communities. Effective assessment of health-impact risk from air pollution is important for supporting decisions of the related detection, prevention, and correction efforts. However, the quality of information available for environmental/health risk assessment is often not satisfactory enough to be presented as deterministic numbers. Stochastic method is one of the methods for tackling those uncertainties, by which uncertain information can be presented as probability distributions. However, if the uncertainties can not be presented as probabilities, they can then be handled through fuzzy membership functions. In this study, an integrated fuzzy-stochastic modeling (IFSM) approach is developed for assessing air pollution impacts towards asthma susceptibility. This development is based on Monte Carlo simulation for the fate of SO₂ in the ambient environment, examination of SO₂ concentrations based on the simulation results, quantification of evaluation criteria using fuzzy membership functions, and risk assessment based on the combined fuzzy-stochastic information. The IFSM entails (a) simulation for the fate of pollutants in ambient environment, with the consideration of source/medium uncertainties, (b) formulation of fuzzy air quality management criteria under uncertain human-exposure pathways, exposure dynamics, and SPG-response variations, and (c) integrated risk assessment under complexities of the combined fuzzy/stochastic inputs of contamination level and health effect (i.e., asthma susceptibility). The developed IFSM is applied to a study of regional air quality management. Reasonable results have been generated, which are useful for evaluating health risks from air pollution. They also provide support for regional environmental management and urban planning.     

基于ABAQUS-ANFIS-MCS的岩质边坡可靠性分析

针对岩质边坡工程稳定性分析中参数的不确定性,基于ABAQUA建立了平面破坏型边坡有限元分析模型。并用该模型进行了边坡稳定状态的数值模拟,以获得进行ANFIS分析的数据。同时基于自适应神经模糊推理系统建立了岩体力学参数与边坡抗滑力和下滑力的映射模型,分析得到抗滑力和下滑力的统计特征。根据蒙特卡罗模拟方法用MATLAB语言编写了求解边坡的破坏概率和可靠度的计算程序,对湖南雪峰水泥原料矿山的露天矿边坡进行可靠度分析。研究结果表明,该方法具有避免编写冗长的有限元计算程序、节省机时、计算精度高的优点。     

燕山地区早侏罗世岩浆活动热供给的数值模拟

燕山地区燕山期发育大量的岩浆岩, 如此大规模的岩浆活动(热)的来源一直是一个谜。 本文利用有限元的热传导模拟反演可能的热供给。 模型假设温度1250 ℃、 面积905.86 km²半圆面形玄武岩浆底侵到36.6~50 km深的陆壳底部, 陆壳的地温梯度随着克拉通的破坏而逐渐升高。 数值模拟的主要结论: ① 早侏罗世时期的地温曲线表明, 要使围岩发生熔融, 所需要的底侵玄武岩岩浆量是非常大的, 基于燕山地区实际产出的早侏罗世时期的酸性岩, 反演产生81 km²的花岗岩需要的最少底侵玄武岩岩浆量为1053 km²; ② 早侏罗世(J₁)的模型温度场表明, 随着时间的演化, 在40～50 km处水平方向的围岩温度升高明显, 形成很明显的一条高温带或熔融带, 该高温带或者熔融带可能成为后期的构造薄弱面, 加上榴辉岩相变造成的密度增加引起下坠, 达到临界值时, 就会出现垮落, 因此本文从数值模拟的角度, 支持拆沉作用的发生。     

基于GIS的北京54坐标与西安80坐标转换方法与应用

对北京54坐标与西安80坐标转换原理进行了论述.结合工作中遇到的一些实际问题,列举了两个坐标转换实例.对“辽宁省矿业权实地核查”成果深度研究,获得了全省1/5万各图幅的北京54与西安80坐标转换改正值.对全省坐标转换改正值进行分析,提出了常用的七参数布尔莎模型以及三参数坐标转换适应范围.阐述了利用MapGIS软件进行北京54坐标与西安80坐标转换步骤.     

多种建模方法耦合建立冲积扇三维构型模型:以克拉玛依油田六中东区下克拉玛依组为例

以克拉玛依油田六中东区下克拉玛依组为例,通过对8口小井距的密闭取心井及周围24口井的构型特征分析,建立了研究区目的层段的三维构型模型。分析得到冲积扇不同亚相实用的构型建模方法：冲积扇扇根为泛连通体,各级构型展布范围不大,主要为片流砂砾体,三维构型建模适合用基于目标的模拟方法;扇中主要构型单元为漫流细粒、辫流水道和漫流砂体,辫流水道与漫流砂体有明显的接触分带关系,适合用截断高斯模拟方法;扇缘主要构型单元为漫流细粒,少量分布径流水道和漫流砂体,适合用序贯指示及基于目标的模拟方法。最终建立的三维构型模型能较好地体现了各级构型单元在平面上和垂向上的展布范围和接触关系。为后期剩余油分布的预测、井网调整及剩余油挖潜提供了准确的依据。     

EDAS-C24型数字测震仪实时数据的解码及加速度和位移仿真的实现

本文尝试使用了一种图形编程语言进行数据解码和仿真研究,阐述了用该语言实现EDAS-C24型数字测震仪实时数据流的解码过程,提出了在G语言下利用数字滤波器逼近模拟积分器及模拟微分器响应实现对解码数据实时仿真的方法,并通过设定频带宽度,比较了设计的补偿滤波响应和实际的幅频响应的一致性.结果表明,在设定的频带内,补偿滤波响应和实际的幅频响应是一致的,仿真的精度是理想的,成果已经在广东省地震科普馆的地震互动区部署运行,取得了一定的实效.     

应用OpenSees计算双钢管高强砼柱的水平力—位移滞回曲线

应用OpenSees计算外方内圆复合钢管高强混凝土柱（简称双钢管高强混凝土柱）的水平力—位移滞回曲线。分析了双钢管高强混凝土柱的单元和截面纤维划分。钢管材料采用双线性模型Steel02,混凝土模型采用Concrete02,圆钢管内和钢管之间的混凝土采用Susantha模型,考虑钢管对混凝土的约束作用,计算得到的水平力—位移滞回曲线与试验结果符合较好。在此基础上,应用OpenSees对双钢管高强混凝土柱进行参数影响分析,讨论了轴压比、方钢管壁厚（宽厚比）、径宽比、径厚比对双钢管高强混凝土柱抗震性能的影响。结果表明：增大轴压比,延性降低;增大方钢管壁厚（减小宽厚比）,水平承载力增大;增大圆钢管直径和壁厚,有助于提高双钢管高强混凝土柱的竖向和水平承载力能力,增大耗能能力。     

Back calculation of soil hydraulic parameters based on HYDRUS-1D

Soil hydraulic parameters are the basis for simulating and calculating the progress of soil water movement and salt transport, and the parameters back-calculation method is simple and effective to determine those parameters. HYDRUS-1D software can simulate the movement of water, salt and heat of soil, as well as realize the inverse calculation of the soil hydraulic parameters through utilizing measured data. Based on the soil moisture content and negative-pressure data monitored in the Erdaoqiao test field of HangjinRear Banner ofInner MongoliaAutonomous Region, soil hydraulic parameters were inversely calculated, and the parameters were verified by utilizing the monitored data of soil with the same lithology under different conditions. The results show that soil moisture content and negative-pressure profile calculated by the soil hydraulic parameters through this method coincide comparably well with the measured results. This indicated that the soil hydraulic parameters obtained through this method were suitable for the moisture movement calculation of soil with the same lithology in field scale