بررسی قابلیت عملکرد تراوایی در سیستم های زهکش متشکل از ژئوتکستایل و خاک تحت اثر فشار

نوع مقاله : مقاله پژوهشی

نویسندگان

دانشکده مهندسی عمران، دانشگاه سمنان، سمنان، ایران

چکیده

یکی از این مهمترین کاربردهای ژئوتکستایلها در پروژههای عمرانی استفاده از آن‌ها به عنوان سیستم زهکش و یا فیلتراسیون درمجاورت خاک می‌باشد. مزایای متعدد استفاده از این نوع مصالح و همچنین بررسی عوامل موثر بر عملکرد آنها همچون خواص تراوایی و یا فیلتراسیون مدت‌هاست که مورد توجه محققان بوده و تاکنون روشهای مختلفی چه بصورت آزمایشگاهی و یا نظری جهت ارزیابی آنها ابداع و یا پیشنهاد شده است. یکی از مواردی که تاکنون کمتر مورد بررسی قرارگرفته، اثر تغییرات فشار بر عملکرد تراوایی سیستم ژئوتکستایل- خاک می‌باشد. در این مقاله نتایج تحقیقات آزمایشگاهی در رابطه با تاثیر فشار سربار بر مقدار تراوایی دو نمونه ژئوتکستایل بافته نشده در یک سیستم ژئوتکستایل- خاک ارائه شده است. بدین منظور یک سلول اندازه‌گیری ویژه جهت آزمونهای سنجش قابلیت تراوایی در سیستم خاک و ژئوتکستایل، طراحی و ساخته که به کمک آن اثر تغییر فشار سربار بر خواص هیدرولیکی سیستم اندازه گیری شده است. نتایج این تحقیق نشان می‌دهد با افزایش فشار سربار میزان نفوذپذیری سیستم زهکش به صورت غیر خطی تغییر پیدا خواهد کرد. همچنین مقایسه بین تراوایی دو نوع ژئوتکستایل در سیستم ژئوتکستایل خاک نشان داد که ضخامت ژئوتکستایل اثر قابل توجهی بر روی تراوایی خواهد داشت.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Geotextile’s Permeability Performance Measurements in Drainage Systems Under Pressure

نویسندگان [English]

  • R. Nateghi
  • A.H. Haddad
Department of Civil Engineering, Semnan University, Semnan, Iran
چکیده [English]

One of the most important applications of geotextiles is as drainage and filtration adjacent soil in civil engineering projects. The using of this material has several benefits such as such as permeability and filtration that effect of these benefits, theoretical or experimental, have been evaluated by researchers. One of the important issues is the effect of contact pressure on permeability of geotextile-soil systems which has been less investigated. In this paper, the impact of overhead pressure on permeability of the soil in the vicinity of nonwoven geotextiles in a drainage system has been investigated by experimental tests. For this purpose, a special measuring cell was designed and built in soil and geotextile system which the hydraulic properties were evaluated in variation of pressure. The results showed that the variation of system permeability is non-linear in variation of overhead pressure. Also the thickness of geotextile has important effect on the permeability in a soil-geotextile system.

کلیدواژه‌ها [English]

  • Nonwoven Geotextile
  • Filtration
  • Drainage
  • Clogging
  • Permeability
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