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421.
The clay-core rockfill dam is a multibody contact system in which the hydromechanical response of the clay core plays a crucial role. This complex problem is highly challenging to model numerically. We present a numerical approach that considers the multibody contact, consolidation, and strong geometric and material nonlinearities for the modeling of clay-core rockfill dams. Within the framework of the dual mortar finite element method, the presented approach considers the contact bodies as independent porous media continuums. The nonlinear contact conditions are derived based on the effective contact traction on contact interfaces and pore pressure continuity. The weak forms are obtained by introducing Lagrange multipliers as additional unknowns, which are then condensed through an extended general transformation. The presented method is first validated with a patch test considering the contact between two porous media. Then, a three-dimensional analysis of the Rumei clay-core rockfill dam is performed. The main numerical analysis concerns are the two observation galleries planned for construction inside the clay core. The galleries consist of dozens of tunnel-like concrete blocks, giving rise to complex concrete-concrete and concrete-clay contacts. The discontinuous separation and sliding between concrete blocks are investigated. For the concrete-concrete contact, both hard and soft joint approaches are evaluated and compared. The pore pressure results of the concrete structures are also analyzed. 相似文献
422.
邓忠文 《地质灾害与环境保护》2012,23(1):45-49
水电工程建设中,坝址区岩体风化特征是最受关注的问题之一。对大渡河中游某电站坝址区花岗岩岩体风化特征进行研究,分析影响其风化特征的控制因素,并指出风化作用对工程的影响。 相似文献
423.
钻探是水利水电工程勘探中获取地下信息最直接、最重要的手段,钻探质量对水利工程的投资和安全具有极其重大的影响。绳索取心是提高钻探质量十分重要的技术,在国土资源、冶金、煤炭等部门得到了广泛的应用。但是将该技术应用于水利水电工程勘探还存在压水试验、绳索取心钻具不匹配、冲洗液限制等问题。通过对上述问题的分析和研究,提出了解决思路和方法,且在工程实践中取得了良好的效果。特别是研究设计的不提大钻压水试验方法,将压水试验和绳索取心钻进有机地结合在一起,很好地解决了绳索取心钻进难以适应水利水电勘探的关键技术难题。 相似文献
424.
水利水资源要素是关系国计民生的重要信息。如何管理和运用好历史积累下来的相关信息资料是关系到未来水利规划建设是否科学与高效的基础工作。笔者结合工作实际,探索基于地理空间技术的水利要素数据库建设与维护的方法,试图解决基础水利资料的统一性,历史信息的连续性,减少水利勘测和设计的重复性工作,科学地为水利建设服务。 相似文献
425.
Abstract Streamflow in the Himalayan rivers is generated from rainfall, snow and ice. The distribution of runoff produced from these sources is such that the streamflow may be observed in these rivers throughout the year, i.e. they are perennial in nature. Snow and glacier melt runoff contributes substantially to the annual flows of these rivers and its estimation is required for the planning, development and management of the water resources of this region. The average contribution of snow and glacier melt runoff in the annual flows of the Satluj River at Bhakra Dam has been determined. Keeping in view the availability of data for the study basin, a water balance approach was used and a water budget period of 10 years (October 1986-September 1996) was considered for the analysis. The rainfall input to the study basin over the water budget period was computed from isohyets using rainfall data of 10 stations located at different elevations in the basin. The total volume of flow for the same period was computed using observed flow data of the Satluj River at Bhakra Dam. A relationship between temperature and evaporation was developed and used to estimate the evapotranspiration losses. The snow-covered area, and its depletion with time, was determined using satellite data. It was found that the average contribution of snow and glacier runoff in the annual flow of the Satluj River at Bhakra Dam is about 59%, the remaining 41% being from rain. 相似文献
426.
427.
空间集聚会导致区域生产要素密度的提高及其空间结构和形态的变化,一直是地理学、经济学领域研究的热点.首先对国外空间集聚相关研究进行了回顾,涉及到空间集聚的理论探索、空间集聚程度与效应、分布特征及其影响因素的实证分析等.然后梳理国内空间集聚研究发现,国内相关研究主要集中在20世纪90年代以后,且对集聚理论与测度方法本身研究较少,而以实证研究居多.最后对国内外相关研究进行了简评,并对国内相关研究提出了展望,认为应该加强相关理论和方法研究,注重社会调查,加强微观企业层面的集聚研究,考虑集聚效应中时空交互作用的影响,并重视集聚与区域经济和区域空间结构关系的研究,以及加强地理学和经济学对空间集聚研究的相互借鉴和融合. 相似文献
428.
Impacts of changing climate on the hydrology and hydropower production of the Tagus River basin
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Anastasia Lobanova Hagen Koch Stefan Liersch Fred F. Hattermann Valentina Krysanova 《水文研究》2016,30(26):5039-5052
The Tagus River basin is an ultimately important water source for hydropower production, urban and agricultural water supply in Spain and Portugal. Growing electricity and water supply demands, over‐regulation of the river and construction of new dams, as well as large inter‐basin and intra‐basin water transfers aggravated by strong natural variability of climate in the catchment, have already imposed significant pressures on the river. The substantial reduction of discharge is observed already now, and projected climatic change is expected to alter the water budget of the catchment further.In this study, we address the effects of projected climate change on the water resources availability in the Tagus River basin and influence of potential changes on hydropower generation of the three important reservoirs in the basin. The catchment‐scale, process‐based eco‐hydrological model soil and water integrated model was set up, calibrated and validated for the entire Tagus River basin, taking into account 15 large reservoirs in the catchment. The future climate projections were selected from those generated within the Inter‐Sectoral Impact Model Intercomparison Project. They include five bias‐corrected climatic datasets for the region, obtained from global circulation model runs under two emissions scenario – moderate and extreme ones – and covered the whole century. The results show a strong agreement among model runs in projecting substantial decrease of discharge of the Tagus River discharge and, consequently, a strong decrease in hydropower production under both future climate scenarios. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
429.
430.
通过对工程边坡以上自然边坡坡面危险源的调查分析评价,得出环境边坡对工程边坡的影响,提出影响工程边坡的环境边坡的危险源区域及其处理建议。 相似文献