共查询到20条相似文献，搜索用时 125 毫秒
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基于ANSYS与OpenGL的高速公路结构物仿真建模及三维地层地表修剪方法 总被引：1，自引：0，他引：1
现代三维视景建模与仿真技术在高速公路工程选线、施工以及运营管理中具有良好的应用前景。结构物的仿真建模以及能反映施工前后地表形态变化的三维地层模型研究是高速公路信息化中的重要问题。介绍了一种借用ANSYS有限元分析软件提取结构物三维模型表面几何信息的简便方法;结合OpenGL纹理贴图技术,实现了结构物的仿真建模;针对结构物施工后对地表形态改变较大的问题,提出利用结构物表面数据对三维地层模型地表网格进行修剪的方法--地表网格竖直投影修剪法。把上述方法应用到广东省某高速公路高边坡的三维视景仿真建模中,结果表明,边坡的仿真模型较逼真。三维地层模型修剪后的地表形态与真实情况接近,验证了方法的合理性、可靠性。 相似文献
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随着人口的增长、经济的发展,一些新高速公路的建设不可避免地经过岩溶发育地区,水任- 南宁高速公路No. 4合同段大约有10km穿过岩溶极为发育的岩溶谷地,下伏著名的地苏地下河系,对路基的稳定性造成巨大威胁。本文以该路段为例,从多源空间数据的管理、数据可视化、动态分段、数据查询、空间分析和专题地图制作等方面介绍GIS在高速公路岩溶路基病害研究中的应用。 相似文献
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现阶段,1∶25万地质图受地理底图涉密的限制,在地质工作和国民经济中的利用受到严重制约。2010年国家测绘局发布1∶25万公众版地形图,提供给社会作为公开出版之用,利用公开出版地形图可以编制精度要求不高的旅游图等示意性图件。本文开展了1∶25万公众版地形图应用于1∶25万地质图的实验研究,提出了一套将地质图套合在公众版地形图上的处理流程和方法:主要包括格式转换、坐标投影转换、地理要素替换、套合分析与处理、地图整饰等,实验结果存在200～500 m的无定向误差,可提供精度要求不高的地质图浏览、展示使用,较难应用到实际的地质工作中。 相似文献
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陈爱新 《物探化探计算技术》2002,24(1):54-57
作者在本文中利用有限元方法模拟电阻率成象测井。为了实现有限元离散网络的合理自动剖分和降低程序设计的难度，对倾斜的地层情形，作者在文中采用了空间变换方法进行处理，并对一些典型的倾斜地层模型进行了模拟测量，并给出了其电阻率井壁成象结果，直观反映井壁地层特征。 相似文献
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变质火山岩、火山碎屑岩的绿片岩相成岩格子可用阳起石—黑云母—方解石—绿泥石—绿帘石—白云母六相三元系和钠长石—阳起石—黑云母—方解石—绿泥石—绿帘石六相三元系成岩格子来表示,石英往往为过剩组分。在只讨论两个强度相同的变量前提下,每个六相三元系的成岩格子都只可能有一对成对的成岩格子,且这对成岩格子的非封闭双变区的分区相同、分区之间的边界斜率相同、相应的单变线的排列顺序也相同,因此,六相三元系的每个成岩格子中的不变点数、单变线数、和双变区数之间的关系可用数学式来表示。 相似文献
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基于MapObjects 2.1控件的地图投影变换方法的实现 总被引：2，自引：0，他引：2
为了在同一地理信息系统内或者不同的地理信息系统之间实现数据交换、配准和共享以及对其进行空间叠加、缓冲区分析、最佳(短)路径分析等空间分析,必须保证其在统一的坐标系下具有相同的地图投影,因此地图投影变换显得尤为重要.采用Visual Basic 6.0作为软件开发平台,利用MapObjects控件编程实现了各种常见地图投影之间的任意变换. 相似文献
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Map sheets have been often used as a basic spatial unit for managing spatial data produced from paper maps. This often results
in incompatibility between adjacent map sheets, because spatial objects do not cross the boundaries smoothly and even the
boundaries themselves do not match their neighbors exactly. To solve the problem this paper proposes a computational procedure
for joining separate map sheets to obtain seamless spatial data. Line objects digitized separately in different map sheets
are considered, which are frequently used to represent road networks, gas pipelines, and boundaries of polygon objects. The
procedure consists of three steps: (1) extraction of end nodes, (2) detection of matching nodes, and (3) transformation of
the map sheet. Each step goes interactively so that unexpected errors can be avoided by human observation. To test the validity
of the procedure, map sheets are combined containing the road network data of Tokyo 23-ku area, Japan.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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This paper extends the multipoint flux-approximation (MPFA) control-volume method to quadrilateral grids for which the adjacent cells do not necessarily share corners. Examples are grids with faults and locally refined grids. This paper gives a derivation of the method for such grids. The difference between two-point flux-approximation (TPFA) results and MPFA results for faults and local grid refinements is demonstrated for synthetic problems. Further, the results are compared with results from uniform fine-grid simulations. The effect of repeated fault patterns as well as anisotropy is investigated. Large errors may be found for the TPFA method for flow through a series of faults in an anisotropic medium. Finally, a comparison is done for a reservoir field application. 相似文献
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贵州省公路工程岩溶环境区划 总被引：7，自引：1，他引：6
为了反映岩溶对公路建设影响的区域性特点,选择贵州省开展公路工程岩溶环境区划工作,提出了岩溶地区公路工程岩溶环境区划的原则和指标体系、建立了评价模型。运用层次分析法和GIS技术,绘出了岩溶对公路影响程度分区图。将贵州省划分为4个影响区,即西部以高～中影响为主的地区、东北部以中～高影响为主的地区、中部以中等影响为主的地区和低影响区。通过对贵州省公路路网和评价结果的综合分析,在12 462 km省道以上公路中,大约有6 265 km公路处于高影响区,而在1 587 km已建和在建高速公路中,有567 km处于高影响区,将对贵州公路规划、建设、养护与管理起到很好的指导作用。 相似文献
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Apip Kaoru Takara Yosuke Yamashiki Kyoji Sassa Agung Bagiawan Ibrahim Hiroshi Fukuoka 《Landslides》2010,7(3):237-258
This paper describes the potential applicability of a hydrological–geotechnical modeling system using satellite-based rainfall
estimates for a shallow landslide prediction system. The physically based distributed model has been developed by integrating
a grid-based distributed kinematic wave rainfall-runoff model with an infinite slope stability approach. The model was forced
by the satellite-based near real-time half-hourly CMORPH global rainfall product prepared by NOAA-CPC. The method combines
the following two model outputs necessary for identifying where and when shallow landslides may potentially occur in the catchment:
(1) the time-invariant spatial distribution of areas susceptible to slope instability map, for which the river catchment is
divided into stability classes according to the critical relative soil saturation; this output is designed to portray the
effect of quasi-static land surface variables and soil strength properties on slope instability and (2) a produced map linked
with spatiotemporally varying hydrologic properties to provide a time-varying estimate of susceptibility to slope movement
in response to rainfall. The proposed hydrological model predicts the dynamic of soil saturation in each grid element. The
stored water in each grid element is then used for updating the relative soil saturation and analyzing the slope stability.
A grid of slope is defined to be unstable when the relative soil saturation becomes higher than the critical level and is
the basis for issuing a shallow landslide warning. The method was applied to past landslides in the upper Citarum River catchment
(2,310 km2), Indonesia; the resulting time-invariant landslide susceptibility map shows good agreement with the spatial patterns of
documented historical landslides (1985–2008). Application of the model to two recent shallow landslides shows that the model
can successfully predict the effect of rainfall movement and intensity on the spatiotemporal dynamic of hydrological variables
that trigger shallow landslides. Several hours before the landslides, the model predicted unstable conditions in some grids
over and near the grids at which the actual shallow landslides occurred. Overall, the results demonstrate the potential applicability
of the modeling system for shallow landslide disaster predictions and warnings. 相似文献
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I. Aavatsmark G. T. Eigestad R. A. Klausen M. F. Wheeler I. Yotov 《Computational Geosciences》2007,11(4):333-345
This paper investigates different variants of the multipoint flux approximation (MPFA) O-method in 2D, which rely on a transformation
to an orthogonal reference space. This approach yields a system of equations with a symmetric matrix of coefficients. Different
methods appear, depending on where the transformed permeability is evaluated. Midpoint and corner-point evaluations are considered.
Relations to mixed finite element (MFE) methods with different velocity finite element spaces are further discussed. Convergence
of the MPFA methods is investigated numerically. For corner-point evaluation of the reference permeability, the same convergence
behavior as the O-method in the physical space is achieved when the grids are refined uniformly or when grid perturbations
of order h
2 are allowed. For h
2-perturbed grids, the convergence of the normal velocities is slower for the midpoint evaluation than for the corner-point
evaluation. However, for rough grids, i.e., grids with perturbations of order h, contrary to the physical space method, convergence cannot be claimed for any of the investigated reference space methods.
The relations to the MFE methods are used to explain the loss of convergence.
Wheeler was partially supported by NSF grant DMS 0411413 and the DOE grant DE-FGO2-04ER25617. Yotov was supported in part
by the DOE grant DE-FG02-04ER25618, the NSF grant DMS 0411694 and the J. Tinsley Oden Faculty Fellowship, The University of
Texas at Austin. 相似文献
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DU Guoliang ZHANG Yongshuang YANG Zhihu Javed IQBAL TONG Bin GUO Changbao YAO Xin WU Ruian 《《地质学报》英文版》2017,91(2):658-668
The eastern Himalayan syntaxis is one of the most tectonically active and earthquake-prone regions on Earth where earthquake-induced geological disasters occur frequently and caused great damages. With the planning and construction of Sichuan-Tibet highway, Sichuan-Tibet railway and hydropower development on the Yarlung Zangbo River etc. in recent years, it is very important to evaluate the seismic landslide hazard of this region. In this paper, a seismic landslide hazard map is produced based on seismic geological background analysis and field investigation using Newmark method with 10% PGA exceedance probabilities in future 50 years by considering the influence of river erosion, active faults and seismic amplification for the first time. The results show that the areas prone to seismic landslides are distributed on steep slopes along the drainages and the glacier horns as well as ridges on the mountains. The seismic landslide hazard map produced in this study not only predicts the most prone seismic landslide areas in the future 50 years but also provides a reference for mitigation strategies to reduce the exposure of the new building and planning projects to seismic landslides. 相似文献
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Yacine Achour Abderrahmane Boumezbeur Riheb Hadji Abdelmadjid Chouabbi Victor Cavaleiro El Amine Bendaoud 《Arabian Journal of Geosciences》2017,10(8):194
This research work deals with the landslide susceptibility assessment using Analytic hierarchy process (AHP) and information value (IV) methods along a highway road section in Constantine region, NE Algeria. The landslide inventory map which has a total of 29 single landslide locations was created based on historical information, aerial photo interpretation, remote sensing images, and extensive field surveys. The different landslide influencing geoenvironmental factors considered for this study are lithology, slope gradient, slope aspect, distance from faults, land use, distance from streams, and geotechnical parameters. A thematic layer map is generated for every geoenvironmental factor using Geographic Information System (GIS); the lithological units and the distance from faults maps were extracted from the geological database of the region. The slope gradient, slope aspect, and distance from streams were calculated from the Digital Elevation Model (DEM). Contemporary land use map was derived from satellite images and field study. Concerning the geotechnical parameters maps, they were determined making use of the geotechnical data from laboratory tests. The analysis of the relationships between the landslide-related factors and the landslide events was then carried out in GIS environment. The AUC plot showed that the susceptibility maps had a success rate of 77 and 66% for IV and AHP models, respectively. For that purpose, the IV model is better in predicting the occurrence of landslides than AHP one. Therefore, the information value method could be used as a landslide susceptibility mapping zonation method along other sections of the A1 highway. 相似文献
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浙江省永嘉县滑坡灾害危险性区划 总被引：7，自引：0，他引：7
永嘉县是浙江省滑坡灾害发生频繁的区县之一,其滑坡受地质、地形和人类工程活动等因素的影响。本文根据永嘉县滑坡灾害分布情况,选择了影响滑坡分布的主要因素,将各种因子归一化处理后转换成相同分辨率的定量数据,选择了逻辑回归分析模型和信息量模型进行滑坡灾害危险性评价。在逻辑回归模型中,利用SPSS软件,通过逐步回归分析筛选出影响滑坡的最直接的因子,计算出各个因子的回归系数,得到逻辑回归方程,据此编制了危险性预测分区图。在信息量模型中,通过MAPGIS软件及其二次开发的信息量模型,对永嘉县滑坡灾害进行了危险性区划,并依信息量法的结果编制了该区的危险性预测分区图。两种方法所编制的危险性分区图中高危险区和中危险区重合率达到了87%,具有很高的一致性,起到了相互验证的作用,为滑坡的有效防治提供了依据。最后根据"云娜"台风期间永嘉县实际灾害发生情况的资料分析,新灾害点绝大部分落在危险性预测区中的高危险区,表明模型的预测准确率很高。 相似文献
16.
Muheeb M. Awawdeh Mohammad A. ElMughrabi Mohammad Y. Atallah 《Environmental Earth Sciences》2018,77(21):732
Road instability along the Jerash–Amman highway was assessed using the weighted overlay method in Geographic Information System environment. The landslide susceptibility map was developed from nine contributing parameters. The map of landslide susceptibility was classified into five zones: very low (very stable), low (stable), moderate (moderately stable), high (unstable), and very high (highly unstable). The very high susceptibility and high susceptibility zones covered 15.14% and 31.81% of the study area, respectively. The main factors that made most parts of study area prone to landslides include excessive drainage channels, road cuts, and unfavorable rock strata such as marl and friable sandstone intercalated with clay and highly fractured limestone. Fracture zones are a major player in land instability. The moderate and high susceptibility zones are the most common in urban (e.g., Salhoub and Gaza camp) and agricultural areas. About 34% of the urban areas and 28.82% of the agricultural areas are characterized by the high susceptibility zone. Twenty percent of the Jerash–Amman highway length and 58% of the overall highway length are located in the very high susceptibility zone. The landslide susceptibility map was validated by the recorded landslides. More than 80 of the inventoried landslides are in unstable zones, which indicate that the selected causative factors are relevant and the model performs properly. 相似文献
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Xifei Huang Xinhao Wang Jingjing Pei Ming Xu Xiaowu Huang Yun Luo 《Natural Hazards》2018,93(3):1181-1202
As the industrialization process accelerates in developing countries, road accidents involving hazardous materials are increasing, and the threat associated with these accidents to areas along the highway cannot be ignored. The main objective of this paper is to contribute information regarding risk quantification, risk prevention, and control by government managers in areas along the highways. Thus, the risk assessment of the area along the highway (RAAH) method was established and applied as a regional risk prevention policy. Considering that the damage caused by accidents can vary substantially between different surroundings, the RAAH method was used as an integrated function comprising of accident frequency, intensity and vulnerability along the route, and the vulnerability system reflected the characteristics of the social and environmental factors in the study area. Then, in this study, we implemented this assessment model in geographic information system and applied it to a typical section of the Beijing–Tibet Highway in Beijing, China, to demonstrate its functionality and utility. A risk map was successfully obtained, and it showed that this method not only effectively reveals the neglected high-risk units but also can be used to provide technical support to the regional government to identify the blind spots and strengthen their risk management. 相似文献
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通过区域地质调查、大比例尺平面图测绘、滑坡微地貌和变形破坏特征测量、地球物理勘探等手段,对国道212线石阏子滑坡特征和形成演化机制进行了系统研究。研究成果表明,它并非是在洪积扇或泥石流基础上发育的滑坡,而是在区域性断裂带基础上,多次滑动形成的"立交桥"式特大型滑坡。研究结果为G212线石阏子滑坡稳定性评价和治理,以及为拟建的兰州-重庆-海口高速公路和兰渝铁路的选线和设计提供理论指导。 相似文献
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Flood disaster has become one of the most damaging natural disasters for the highway transportation all around the world, especially its destructive effects on highway infrastructures. In order to better understand the ruinous influence of flood disaster on highway transportation in China, this paper proposes an alternative evaluation index of highway flood disaster risk from three aspects, namely the disaster-causing factors, disaster-inducing environment, and disaster-bearing subjects. This paper also puts forward some targeted suggestions for the risk management, including two aspects: physical protection measurement and organization and management measurement. Moreover, this paper develops a highway flood disaster risk management system by using the ArcGIS technology.
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