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731.
Influence of rainfall on the deformation and stability of a slope in overconsolidated clays: a case study 总被引:2,自引:0,他引:2
The behaviour of an instrumented unstable slope in a profile of weathered overconsolidated clay has been analysed. Available
field investigation data and laboratory tests were integrated in a coupled hydromechanical model of the slope. Particular
attention was given to the unsaturated soil conditions above the water table and to the influence of the rainfall record.
Recorded pore-water pressures helped to identify the hydrogeological conditions of the slope. The coupled model was used to
compute slope deformations and the variation of safety with time. Actual rainfall records were also integrated into the analysis.
Comparison of measurements and calculations illustrate the nature of the slope instability and the complex relationships between
mechanical and hydraulic factors.
Electronic Publication 相似文献
732.
LIU Yan-li 《地理学报(英文版)》2000,(1)
Background of Study on Allocation of Agricultural Productive Factors in ChinaAgricultal productiVe factors include land, labor, fendirer, approved variety, fann machinery, waterconservanCy facilihes, etc. The allocation of aghcultural productiVe factors is defined as the combinationof agricultural productiVe factors corresponding to regional natural condihons and economic situationIt is a requirement of Chinese agricultural prachce to StUdy the allocation of agricultUlal produchvefactors… 相似文献
733.
本文采用蚀源区判别图解QFL和QpLsLv、微量元素图解Th -Co -Zr/10、常量元素图解K2O/Na2O -SiO2 和野外地质实测剖面等方法 ,对比如、措勤地体的构造演化进行了分析。发现并证实了在T3-J1 以前比如地体位于措勤地体的北部 :J2 -3 时随着班—恕缝合带的拉张 ,比如地体开始右旋向东滑动 :一直延续到J3-K1 时 ,班—怒缝合带闭合 ,比如地体才就位于目前位置。最后应用1/ZTR指数推测了比如地体在J2 -3 时滑移点的大致位置 (E90°49,N31°34)。 相似文献
734.
根据土高压固结试验的压缩曲线几何特征,提出了基于一定较高压力水平的固结试验结果外推更大压力段的压缩性参数和压缩曲线的方法。实际验证结果表明,该方法简便易行,且精确度较高。 相似文献
735.
Based on the total phosphorous (TP) concentration in sediment core, the TP concentration in lake water quantitatively reconstructed from fossil diatoms and diatom-TP transfer function in the Longgan Lake during the last 200 years, the temperature and precipitation data from meteorological observation for the last 50 years, the temperatures and precipitation sequences of climate simulation for the last 200 years, as well as the amount of the agricultural phosphate fertilizer in Longgan area for nearly 50 years, the characteristic and the law of the nutrient status evolution were analyzed, and the influence of the climatic factor, the anthropologic factor and the aquatic biology factor on the nutrient status evolution and its mechanism were discussed for the Longgan Lake during the last 200 years. The results showed that, in the nearly 200 years, the TP concentration in the sediment core of the Longgan Lake gradually increased, its range of variation was situated between 330-580 mg/kg, the mean value was 388 mg/kg, a nearly 30-year vibration adjustment period existed at 1950 around. The TP concentration in lake water changed in a different way. Before 1950, it had a slow increasing tendency in fluctuated background, to 1950 around it reached up to the mean value (52.18μg/L), and vibrated and adjusted around the mean value, then it fast declined, its change range was situated between 37.75-62.33μg/L. The analyses indicated that, in the centennial time scale, the climate change was the main controlling factor, while in the decadal time scale in the recent 50 years, human activities were the leading factors for the nutrient status evolution of the Longgan Lake. 60% of the variability of the TP concentration in the sediments and 57% of that in lake water were due to human activities. The differentiation between phosphorus concentration in the sediment and in the lake water reflected the response processes and the adjustment abilities of the lake aquatic ecosystems to the lake nutrient level, implying the maintenance and the destruction of the balances between the algae and the aquatic plants, as well as the corresponding accumulating characteristics of the phosphorus. 相似文献
736.
本文对萨尔图油田中部葡萄花油层组的非均质性进行定量半定量研究,认为葡萄花油层组PⅠ2小层层内非均质性最严重,与沉积微相密切相关;单砂层垂向上渗透率的变化以正韵律和复合式韵律为主,局部发育反韵律模式;层内非均质性强弱依次为PⅠ2a、PⅠ3、PⅠ2b、PⅠ1、PⅠ4;层间非均质性在PⅠ3和PⅠ4间表现得最强,其它相对要弱;各小层平面非均质性相差无几,整体表现为较强的非均质性。 相似文献
737.
岩体质量的评价对于各类大型建筑物特别是地下工程建筑物的安全性具有十分重要的作用。文章基于岩石质量指标(RQD)和岩体块度指数(RBI)的理论,通过对甘肃北山1号钻孔的岩心实测资料证明,岩体块度指数在一定程度上能反映岩体的完整性与相应力学性质的变化特点,同时给出钻孔附近岩体质量分类,进而与岩石质量指标所获得的钻孔附近岩体质量评价分级进行对比。对比结果表明:岩体块度指数在岩石质量评价中能更准确地反映其优越性,具有更为显著的工程意义。 相似文献
738.
739.
区域水资源可持续利用评价 总被引:4,自引:0,他引:4
水资源可持续利用评价是可持续发展战略研究的核心问题之一,选取合适的评价方法是正确评价水资源可持续利用的基本前提。在目前提出的评价方法中,关键性的问题是如何合理确定各个评价指标的权重,层次分析法是解决这一问题常用的有效方法。但是,层次分析法没有给出判断矩阵一致性的调整方法;而且评价结果也只能表明各个指标对水资源可持续利用的影响大小,并不能判断研究区水资源可持续利用程度。本文在层次分析法的基础上,探讨了判断矩阵一致性的修正方法,构造出判断水资源可持续利用程度的综合指数,并对云南省水资源可持续利用程度进行评价。 相似文献
740.