کنترل تورم خاک بستر جاده‌های‌ جنگلی با استفاده از مواد پلیمری

نوع مقاله: مقاله پژوهشی

نویسندگان

1 دانشجوی دکتری ‌مهندسی جنگل، دانشکدۀ منابع طبیعی دانشگاه تهران، کرج، ایران

2 استادیار، گروه جنگلداری و اقتصاد جنگل، دانشکدۀ منابع طبیعی دانشگاه تهران، کرج، ایران

چکیده

با اینکه خاک به‌عنوان مصالح بستر بسیاری از سازه­ها مطرح است، برخی خاک‌ها مشکلاتی در سازه‌ها از جمله جاده‌ ایجاد می‌کنند. این خاک‌ها با جذب رطوبت متورم شده و با از دست­دادن آب منقبض می­شوند. تغییرات رطوبت این خاک­ها سبب تغییر حجم آن­ها و در نتیجه اعمال فشار به لایۀ روسازی و در نهایت تخریب جاده می­شود. این امر نشان­دهندۀ اهمیت بررسی‌های لازم برای به­کارگیری روش‌هایی به‌منظور کاهش پتانسیل تورمی این‌گونه خاک­هاست که با وجود اهمیت موضوع، تاکنون مطالعه­ای در این زمینه در جاده­های جنگلی صورت نگرفته است. به­همین دلیل در این پژوهش تأثیر مواد پلیمری بر کنترل تورم خاک به‌عنوان مصالح جاده­های جنگلی بررسی شد. آزمایش‌های تراکم، تورم و فشار تورمی روی خاک شاهد و نمونه­های تیمارشده با درصدهای متفاوت مادۀ پلیمری RPP (019/0، 04/0 و 06/0درصد) صورت گرفت. به­منظور انجام آزمایش تورم و فشار تورمی، نمونه­ها با رطوبت بهینۀ حاصل از آزمایش تراکم تهیه و به‌ شیوۀ تراکم استاتیکی متراکم و سپس به دستگاه تحکیم منتقل شدند. با توجه به نتایج تست­های آزمایشگاهی به­دست‌آمده از این پژوهش افزودن مادۀ پلیمری RPP می­تواند سبب کاهش تورم و فشار تورمی خاک شود؛ به­طوری که با افزایش درصد مادۀ RPP، پتانسیل تورم و فشار تورمی خاک با شدت بیشتری کاهش می­یابد. در نتیجه مادۀ RPP می­تواند گزینه‌ای برای رفع مشکل تورم­زایی خاک­های جنگلی باشد، اما باید بررسی‌های اقتصادی، فنی تکمیلی و مقایسه‌ای در این مورد به‌عمل آید.

کلیدواژه‌ها


عنوان مقاله [English]

SwelliSwelling Control of Forest Road Bed Soil by Polymeric Materials

نویسندگان [English]

  • Fatemeh Musavi 1
  • Ehsan Abdi 2
1 Phd Student of Forest Engineering, Faculty of Natural Resources, University of Tehran, Karaj, I.R. Iran
2 Assistant Professor, Department of Forestry, University of Tehran. Karaj, I.R. Iran
چکیده [English]

Soil is known as the base material for many structure, on the other hand, some soils cause problems for some structures such as roads. Some types of soils absorb moisture and swell then they may shrink when losing water. The changes of moisture in these soil samples cause changes their volume and pressure to layers of the pavement and eventually leads to destruction of roads. Therefore, it is necessary to assess and study methods to improve the swelling properties of these soils. Unfortunately no study has been conducted in this field in forest environment yet. In this study the effect of RPP as a polymer stabilization for controlling swelling of forest soils was investigated. Compaction tests, swelling potential and swelling pressure on the soil samples treated with different percentages of RPP (0/019, 0/04 and 0/06%) were conducted. In order to test swelling potential and swelling pressures, samples were prepared with optimum moisture determined by compaction test and were compressed by static compaction method and then moved to consolidate apparatus. According to the results of this study, adding of RPP can decrease swelling potential and swelling pressures of soil slightly and to achieve better results the percentage of RPP, should be increased. The results showed that RPP may be an alternative for swelling control of soil in forest roads but economic and technical studies are needed to determine the mechanism for stabilization and evaluating their performance in field conditions.

کلیدواژه‌ها [English]

  • : Consolidation apparatus
  • swelling properties
  • Swelling control
  • RPP material
  • Forest roads
 

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