عملکرد زهکش‌های افقی و دودکشی در پایداری دیوار حائل شیب‌های خاکی

نوع مقاله : مقاله پژوهشی

نویسندگان

دانشگاه ارومیه، ارومیه، ایران

چکیده

به علت بارندگی‌های شدید، سطح آب زیرزمینی و فشار آب منفذی هر ساله افزایش می‌یابد که این عامل می‌تواند باعث شکست شیب‌های خاکی شود. دیوار حائل یکی از سازه‌هایی است که جهت افزایش پایداری شیب‌های خاکی مورد استفاده قرار می‌گیرد. در این تحقیق با استفاده از نرم‌افزار SLOPE/W پایداری شیب‌ها نسبت به شرایط هیدرولوژیکی بحرانی و با استفاده از نرم‌افزار SEEP/W  فشار حفره‌ای مازادی که باعث ناپایداری دیوار حائل با ارتفاع 10 متر می‌گردد، مورد بررسی قرار گرفت. پارامتر‌های مورد مطالعه عبارت‌اند از: شدت بارش‌ها، جنس خاک، موقعیت قرارگیری زهکش‌ها و قطر زهکش‌ها. هم‌چنین نوع زهکش‌ها نیز به عنوان متغیر واقع شد و از دو نوع زهکش افقی و دودکشی استفاده شد. بر اساس نتایج حاصله، در شرایط بارش شدید در خاک‌های ریزدانه، استفاده از یک زهکش افقی نمی‌تواند پایداری دیوار حائل را تامین کند. این در حالی است که در شرایط مشابه و در خاک‌های درشت دانه، پایداری دیوار حائل توسط یک زهکش افقی تامین می‌شود و زهکش قادر به تخلیه آب مازاد از پشت دیوار خواهد بود. هم‌چنین نتایج بدست آمده برای زهکش‌های دودکشی نشان دهنده پایدارسازی دیوار حائل توسط این زهکش‌ها در بحرانی‌ترین شرایط می‌باشد. در رابطه با محاسبه فشار منفذی و گشتاورهای واژگونی روابط بی‌بعد خطی و غیرخطی رگرسیونی ارائه گردید. روابط رگرسیونی از لحاظ دقت در سطح بالایی قرار دارند و می‌توان از آنها نتایج قابل قبولی را انتظار داشت.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Performance of horizontal and chimney drainage in stability of retaining wall of earthen slopes

نویسندگان [English]

  • meysam nourighanli
  • Farzin Salmasi
Urmia university
چکیده [English]

Due to heavy rainfall, underground water level, and pore water pressure increase each year, which can cause the  failure of the earthen slopes. A retaining wall is one of the main structures that is used to increase the stability of the earthen slope. In the present study, the stability of earthen slopes relative to the critical hydrological cases was simulated by Slope/w software, and the pore pressure behind the retaining walls over 10-meter height which causes instability was simulated using Seep/w software. The studied parameters are precipitation intensity, soil type, position and, the diameter of drainage. Also, the kind of drainage has been considered as a variable parameter and horizontal and chimney drainages were used. Results showed that for fine-grained soils with intensive rain conditions, using one horizontal drainage could not provide the stability of the retaining wall. While in the same conditions, for coarse-grained soils, the retaining wall will be stable by using one horizontal drainage and drainage will be able to discharge all of the excess water behind the retaining wall. Also, the chimney drainage system provided the best results and the stability of the retaining wall did not face any danger under the worst circumstances. For the overturning moment and water pore pressure behind the wall, linear and non-linear regression relations were produced in dimensionless form. The accuracy of the regression relations was proper and acceptable results could be expected.

کلیدواژه‌ها [English]

  • Drainage System
  • Pore Water Pressure
  • Heavy Rainfall
  • Soil Slope
  • Stability
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