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排序方式: 共有1352条查询结果,搜索用时 31 毫秒
1.
根据镇江地震地质情况及防震减灾工作实际,通过需求分析及系统整体设计,建立基于WebGIS的地震信息数据库管理系统。系统采用Oracle数据库、JavaScript语言、Tomcat网站服务器,开发了具有地方特色的地震应急处置快速反应系统,系统可实现震后快速评估、辅助决策、震后趋势分析、震后应急资料产出等功能。实际应用表明,该系统达到了低成本、高效率的预期目标。 相似文献
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Landslides and rock falls along the highway are common geological hazards in Southwest China. As an influencing factor on potential landslides behavior, roads or distance to roads have been successfully used in landslide susceptibility assessments in mountainous area. However, the relationship between the road-cut and the slope stability is not clear. Therefore, we performed two-dimensional slope stability calculation using the general limit equilibrium (GLE)method incorporated in the software SLOPE/W of GeoStudio for stability analysis of slopes. Our studies show that the man-made roads influence on the slope stability mainly exists in two ways:One is to create a new steep slope, which will result in rock falls and shallow landslides along the roads; the other is to influence the stability of the original slope, which will result in comparatively huge landslides. For the latter, our simulation study reveals that the road location, namely at which part of a natural slope to construct a road is important for the slope stability. For a natural slope with a potential slip surface, if a road is constructed at or near the slope toe where the potential slip surface surpasses, it will greatly degrade the slope's factor of safety (Fs) and make the slope unstable; however, if a rode-cut is near the top of the slope, it will increase the slope's Fs and make the slope more stable. The safety location is different for different slope angle, steeper slope needs a higher location for a safety road-cut in comparison with gentle slopes. Moreover, the slope stability decreases when loading a seismic force and it varies with the slope angle. Firstly, the Fs decreases when the slope angle increasing, and when the slope angle reaches 45°, the Fs then becomes greater with the slope angle increasing. 相似文献
3.
为提高受灾地区重建安全性,提出基于ARIO模型的震后重建施工现场安全管理方法。在将建筑设计影响因素划分为直接因素与间接因素的基础上,将ARIO模型引入震后重建施工现场安全管理中,利用其分析施工过程中各产业技术与该地区经济的联系,在考虑经济因素的基础上实现震后施工现场安全管理。设计并构建施工初期数据采集系统、施工前安全管理系统、施工过程中安全管理系统,将ARIO与VR结合,使各系统运行时施工人员能够在虚拟漫游中以第一视角完成虚拟施工,掌握整个工期、流程、所用设备等有关信息,并由辅助专家作出相应指导,实现震后重建施工现场安全系统化管理。提出施工安全辅助建议,以完善灾后重建安全管理方法。实验结果表明,该方法运行后安全系数大于当前方法,其科学性和鲁棒性较强。 相似文献
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Stability analysis of shotcrete supported crown of NATM tunnels with discontinuity layout optimization 下载免费PDF全文
For tunnel constructed by New Austrian Tunnelling Method, the crown is the upper part of tunnel section, constructed during excavation process and supported by shotcrete. The stability of the crown has great influence on the safety of tunnel itself and the buildings above, which correlates, among others, with geometrical setup of tunnel and material properties of shotcrete and soil/rock. In this paper, aiming at analyzing the stability of shotcrete supported crown, a recently presented numerical method discontinuity layout optimization is adopted, which introduces a great amount of potential discontinuities cross over one another and provides a wide search space for efficient upper limit analysis. In the analysis, a well‐established hydration model of cementitious material is implemented for accounting the hydration of shotcrete. Then assumptions based on convergence‐confinement method are used for accounting the 3‐dimensional effect in 2‐dimensional analysis, finally providing time‐space–dependent assessments of stability of shotcrete supported crown. 相似文献
6.
Ramin Vali Jie Li Gholamreza Shams Pieter van Gelder 《Marine Georesources & Geotechnology》2018,36(6):735-748
Evaluation of slope stability, especially in the absence of a proper bed such as marine soils, is one of the most important issues in geotechnical engineering. Using geogrid layers to enhance the strength and stability of embankments is regarded as a commendable stabilization method. On the other hand, groundwater level erratically fluctuates in coastal areas. Therefore, the aim of this research is to study the effects of groundwater level changes on stability of a geogrid-reinforced slope on loose marine soils in Qeshm Island, Iran. At first, geotechnical properties of the site were obtained by comprehensive series of geotechnical laboratory and in situ tests. Then, by simultaneous changes of groundwater level and several parameters such as embankment slope, loading, geogrid length, geogrid number, and tensile strength of geogrid, different characteristics such as embankment safety factor (SF), vertical and horizontal displacements at embankment top and embankment base were studied. It was observed that groundwater level had significant effects on behavior of the embankment. For most of the observations, by decreasing the groundwater level, the displacements decreased and consequently safety factor increased. Increasing the length, number, and tensile strength of geogrid led to the reduction of displacements and an increase in the safety factor. 相似文献
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Jinquan Liu Weizhong Chen Zhiping Deng Taogen Liu 《Marine Georesources & Geotechnology》2020,38(2):144-153
AbstractDue to the strong disintegration and water erosion of completely weathered granite, water and mud inrush disasters are apt to take place in this zone during underwater tunnel construction. The pore, compactness, seepage path length, fracture geometries and their interconnections for water and mud transfer are strongly influenced by confining pressure and waterproof-resistant slab safety thickness. In order to inspect the influence, a series of experiments based on a self-designed testing system and non-Darcy testing method were performed. The results indicated that the water and mud inrush evolution increased with the increase of confining pressure and decreased with the increase of safety thickness. In particular, the confining pressure mainly influences the initial evolution stage, and a critical safety thickness to prevent water and mud inrush is obtained. Besides, the non-Darcy testing method results shows that the water and mud inrush evolution affects the influence of non-Darcy flow. For example, while the safety thickness was smaller than the critical value, the evolution was large and unstable and its behavior transferred into nonlinear. In this case, the flow changed to non-Darcy flow. 相似文献
9.
长白山景区旅游安全风险动态评价研究 总被引:1,自引:0,他引:1
以长白山景区旅游安全为研究对象,以鱼骨图、动态贝叶斯、GIS技术等为基本研究方法,从研究区自然环境、社会环境及责任人为3个方面出发,筛选景区致险因子,构建景区旅游安全风险危险性评价指标体系,利用动态贝叶斯方法综合构建景区旅游安全风险动态评价模型;并以实测数据及景区统计数据为依据,划分景区旅游安全风险评价的4个动态时段,综合实现景区旅游安全风险动态风险评价。研究结果表明:① 中等以上风险区域呈条带状分布;② 高风险区域与主要景点重合;③ 长白山景区安全风险发生高概率的时段发生在第三个时段(12:00~14:00);较高概率发生分别在第二个时段(10:00~12:00)与第四个时段(14:00~16:00);中等概率发生较高的时段在第四个时段(14:00~16:00);较低概率发生在第一个时段(8:00~10:00)。 相似文献
10.
我国城镇化进程和经济发展效果卓著,但消防建设规划与城市扩张发展之间并不协调。虽然现有研究已经运用GIS技术到消防安全监管当中,但依然存在信息联动性不强,可视化程度低的问题。为此,本文基于地理信息系统技术对城市开发区内地理信息数据、多源多时态遥感及航空影像、巡查数据、出租房数据等进行有效整合完善,以建立时空地理信息大数据。笔者利用虚拟化、云计算等技术建立出租房消防安全动态监管平台。此平台为管理部门提供了基于地理信息的决策支持,提升了出租房管理的高效性和科学性。系统的建成和应用对我国的出租房管理信息化工作的开展具有重要意义。 相似文献