基于土性相关蒙特卡罗法的争岗滑坡堆积体可靠性分析

针对澜沧江古水水电站争岗滑坡堆积体工程地质务件,在室内剪切试验、工程类比、参数反演基础上综合确定了岩土体力学参数及其统计分布规律.采用基于黏聚力c与内摩擦角φ相关抽样下的蒙特卡罗法对堆积体典型剖面进行了多种工况下的可靠性分析,预测了其未来的变形失稳特征.研究结果表明:当前堆积体B-B'剖面在正常运行工况下的破坏概率为2...     

Re-situating fieldwork and re-narrating disciplinary history in global mega-geomorphology

In 1985, more than thirty geomorphologists, planetary scientists, and remote sensing specialists gathered at a conference center in Oracle, Arizona, to discuss an emerging area of research that they called “mega-geomorphology.” Building on a conference of the same name held in London in 1981, they argued that new techniques of remote sensing and insights emerging from the study of extraterrestrial planets had created opportunities for geomorphology to broaden its spatial and temporal scope. This new approach was, however, neither unproblematic nor uncontested. In the discussions around mega-geomorphology that took place in the mid-1980s, the perceived conflict between the use of remote-sensing techniques to observe phenomena on vast spatial scales, on one hand, and the disciplinary centrality of fieldwork and field experience to geomorphology, on the other, was a recurrent theme. In response, mega-geomorphologists attempted to re-situate fieldwork and re-narrate disciplinary histories in such a way as to make remote sensing and planetary science not only compatible with geomorphological traditions but also means of revitalizing them. Only partially successful, these attempts reveal that the process of adopting a planetary perspective in geomorphology, as in other earth sciences, was neither straightforward nor inevitable. They also show how the field and fieldwork could remain central to geomorphology while also being extensively revised in light of new technical possibilities and theoretical frameworks.     

核能谱与两类转动惯量的精确表达式

用最小二乘拟合法,将稀土区的能谱实验数据,拟合不同的能谱公式,从而证明E=a〔(1+bI(I+1))~(1/2)-1〕是符合得较好的,本文还推导了与上述能谱相应的两类转动惯量,并以此与实验计算值进行比较,结果仍很满意.     

Accelerated carbonation and leaching behavior of the slag from iron and steel making industry

Ground granulated blast furnace slag(GGBFS)and steelmaking slag have been used as a raw material for cement production or as an aggregate to make concrete,which contribute aluminum,calcium,iron,and silicon oxides.The suitability of the slag for a particular application depends on its reactivity,cost,availability,and its influence on the properties of the resulting concrete.For the interest of durability studying of concrete in the presence of slag,the accelerated carbonation products and leaching behavior of the slag and Portland cement(PC)were studied.The experimental results confirmed that the slag was more resistant to carbonation compared to PC.The carbonation degree of GGBFS reduced by 17.74%;and the carbonation degrees of steelmaking slags reduced by 9.51%-11.94%.Carbonation neutralized the alkaline nature of the hydrated pastes and gave rise to the redox potential of the leachate slightly(30-77 mV).The carbonation also increased the release of most of the elements presented,except for calcium,to the aqueous environment.It is concluded that blend cements(PC plus slag)have economical advantages and better durability compared to PC.     

Water in granulites: implications for the nature and evolution of the lower continental crust

The lower continental crust is one of the most important sphere-layers in the deep earth, and is the direct place where the crust-mantle interactions occur. Granulites are the dominated rocks in the lower crust, and have critical implications for the knowledge of the composition, nature and evolution of the deep crust; fluids are important mediums influencing many geochemical, geophysical and geodynamical characteristics of the lower crust, and may also play a fundamental role in the petrogenesis of granulites and the formation of the lower crusts. In this paper, we review recent advances involved with the deep continental crust, granulites and fluids, and some long-standing debates. Combined with the Fourier-transform infrared spectroscopy (FTIR) analysis performed on the mineral assemblages (cpx, opx, plag and grt) in lower crustal granulite xenoliths and terrains (exposed section) from east China, it is suggested that structural water, dominated by OH, in these nominally anhydrous phases may constitute the most important water reservoir in the deep crust. This structual water may help to understand many lower crustal geological processes and phenomena (e.g. seismic activities and electrical conductive anomalies), and influences from these water must be taken into consideration.