پديد آورندگان :
زمرديان, محمدعلي دانشگاه شيراز - بخش مهندسي آب , عطايي, محمد جعفر دانشگاه شيراز - بخش مهندسي آب
كليدواژه :
نانورس , فرسايش داخلي , پردازش تصوير , عمل آوري
چكيده فارسي :
فرسايش داخلي از عوامل اصلي تخريب سدهاي خاكي است كه براي مقابله با آن از تزريق يا افزودن مواد شيميايي به خاك استفاده مي شود. در اين پژوهش از نانورس به عنوان ماده افزوني بدون خطرات زيست محيطي استفاده شد و فرسايش پذيري نمونه هاي حاوي نانورس با مقادير 0، 1، 1٫5 درصد وزني خاك خشك و زمان عمل آوري 0، 7، 14 و 28 روز با استفاده از روش پردازش تصوير بررسي شد. به منظور انجام مقايسه يي بين مواد افزودني مدرن و سنتي، نمونه يي با 5٪ وزني خاك خشك رس متخلخل استفاده شد. نتايج نشان از تاثير مثبت نانورس بر كاهش فرسايش پذيري خاك شاهد داشت؛ به طوري كه نمونه ي 1٪ نانورس با زمان عمل آوري 14 روز بيشترين مقاومت را نشان داد. افزايش زمان عمل آوري تا 14 روز در همه ي نمونه ها باعث كاهش فرسايش پذيري شد و بعد از آن تاثير به سزايي بر آن نداشت. در مقايسه بين مواد افزودني سنتي و مدرن نيز فرسايش پذيري در نمونه ي حاوي 5٪ رس بنتونيتي 10 برابر نسبت به نمونه ي حاوي 1٪ نانورس كاهش داشت.
چكيده لاتين :
Owing to the fact that the world's population and their need for water are becoming increasingly larger, the construction of structures like dams and levees to profit from water sources and, also, the prevention of possible disasters, are inevitable. Moreover, embankments are more economical and have been immensely under consideration by the expert communities. Internal erosion plays a major role in the failure of embankments. Due to internal erosion of an earth dam water that seeps through the dam, soil particles are carried away from the embankment, foundation, or abutments of the dam. Internal erosion may be a result of inadequate compaction during construction, differential settlement, desiccation, earthquakes, burrowing animals, and/or vegetation roots. The erodibility of the material in the internal erosion flow path and hydraulic stresses are the most important factors in determining the degree of erosion. The challenge in predicting failure due to internal erosion characterizes the material properties relevant to the rate of failure. To prohibit this natural phenomenon, the addion of chemical additives and grouting is highly suggested. In the present study nanoclay devoid of any environmental detrimental effects was utilized. Erodibility of samples contained naoclay with 0, 1 and 1.5 weight percent of dry soil and curing time of 0, 7, 14, 28 days went under investigation through image processing. Furthermore, to make a contrast between the modern and typical additives, another sample containing bentonite clay with 5 weight percent of dry soil was used. The results illustrated that the specimen containing 1 weight percent of nanoclay with a curing time of 14 days possessed the strongest resistance. Curing time of 14 days diminished erodibility in all the specimens; however, the allocation of more curing time had no beneficial effect. In addition, the sample containing 5 wt. % bentonite clay could decrease erodibility to a 10-fold extent, compared to the sample containing 1wt.
