Abstract




 
   

IJE TRANSACTIONS B: Applications Vol. 30, No. 8 (August 2017) 1182-1189   

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  THE INVESTIGATION OF SUBSIDENCE EFFECT ON BURIED PIPES IN 3D SPACE
 
R. Hassani and R. Basirat
 
( Received: March 18, 2017 – Accepted in Revised Form: July 07, 2017 )
 
 

Abstract    Buried pipes in the modern societies are considered as lifelines with a vital and essential role in the human life cycle. The performance of buried pipes is affected by many factors such as ground surface subsidence. In this paper, the effect of subsidence on pipelines is investigated using a three-dimensional numerical modeling developed in FLAC3D software for four types of most commonly used pipes. The numerical results showed that ductile iron, steel, and polyethylene pipes with a diameter of 200 mm are stable in the presence of ground subsidence whereas the asbestos pipes at depths of 1 and 1.5 m are not stable; and thus should be buried deeper. In this regard, polyethylene pipes with equal diameter are recommended instead of asbestos pipes due to the high excavation and earth-filling costs and also environmental problems involved in the implementation of asbestos pipes.

 

Keywords    Buried Pipes, Subsidence, Numerical Modeling, FLAC3D Software

 

چکیده    لوله­هاي مدفون در جوامع مدرن از شریان­هاي حیاتی به شمار می­آید که نقشی حیاتی و اساسی را در چرخه زندگی بشري ایفا می­نماید. در این میان، عوامل مختلفی بر عملکرد لوله­های مدفون تاثیر می­گذارند. یکی از عوامل تاثیرگذار بر لوله­های مدفون، نشست سطح زمین می­باشد. در این مقاله با استفاده از مدل­سازی سه بعدی عددی توسط نرم افزار FLAC3D اثر نشست بر چهار نوع لوله پرکاربرد در خطوط انتقال، بررسی شده است. نتایج عددی نشان دادند که برای لوله­های چدن داکتیل و فولادی و پلی­اتیلن با قطر 200 میلی­متر توانایی تحمل تاثیرات نشست را دارند، اما لوله آزبست توانایی تحمل تاثیرات نشست در اعماق 1 و 5/1 متر را ندارد و بایستی این لوله­ها در اعماق بیشتری مدفون شود. اما، با توجه به افزایش هزینه خاک­برداری و خاک­ریزی، و همچنین مشکلات زیست ­محیطی لوله­های آزبست، پیشنهاد می­شود از لوله پلی­اتیلن با قطر معادل استفاده گردد.

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