نوع مقاله: مروری

نویسندگان

1 کارشناس ارشد گروه عمران، دانشکده فنی، دانشگاه گیلان، رشت، ایران

2 دانشیار دانشکده عمران دانشگاه گیلان

چکیده

پسروی سواحل صخره ای معضلی جدی است که کرانه های چنین سواحلی را در سراسر دنیا تهدید می کند و به معنای تغییر موقعیت خط ساحلی می باشد. تاثیرات پسروی بر تخریب محیط طبیعی ساحل یا سازه های موجود، شناخت ساز و کار پسروی و عوامل موثر بر آن را ایجاب می کند. در اکثر موارد پسروی، به صورت گسیختگی زیر صخره در اثر برخورد امواج به پای آن و جدا شدن ذرات از صخره رخ می دهد. در این مقاله پسروی سواحل صخره ای و چندین مدل جهت برآورد آن، معرفی می گردد. با توجه به اینکه عامل اصلی پسروی، بالاروی امواج در پای صخره است، شرایط فیزیکی مانند عرض ساحل، شیب صخره، وجود سکوهای ساحلی، فرو رفتگی ها و بیرون زدگیها می توانند بر میزان پسروی صخره موثر هستند. از سوی دیگر جنس صخره ها می تواند کنترل کننده سرعت پسروی آنها باشد. لذا برای حصول به نتایج دقیق، باید مدلهای پسروی سواحل صخره ای با توجه به اتلاف انرژی امواج، انباشت و تخلیه رسوبات در پای صخره، همراه با مطالعات دقیق رفتار دینامیکی ساحل و انرژی موج در پریود مشخص آن، بر پایه اصول علمی ژئوتکنیک، آمار و احتمالات، ریاضی و مدلهای هیبریدی حاصل گردد.

کلیدواژه‌ها

عنوان مقاله [English]

A review of the estimation of the coastal cliff retreat methods and it's influenced factors

نویسندگان [English]

  • Shaghayegh Raja 1
  • Mir Ahmad Ahmad Lashteneshaye 2

1 Civil Engineering, Technical Branch, Guilan University, Rasht, Iran

2 Civil Engineering, Technical Branch, Guilan University, Rasht, Iran.

چکیده [English]

Coastal cliff retreat is a serious problem threating such shorelines worldwide, and may be defined as the change in position of the shoreline. Retreat effects on natural coast demolition is required the recognition of the retreat mechanism and it’s influenced factors. In many cases, undercutting of the cliff toe by wave action and subsequent mass failure, is the mechanism by which most cliffs are eroded. This paper has reviewed retreat of coastal cliffs and some models to estimate it. The main cause of retreat is wave run up; as a result physical components such as width of beach, slope angle of the cliff, existence of berms, indentations and outcroppings can be effective on retreat. But then again lithology is a key constituent of rate of recession. To achieve accurate results, cliff retreat models must be attained due to dissipation of wave energy, debris accumulation and discharge at the cliff toe, with exact studies of coast dynamic behavior and wave energy in it’s significant period, based on geotechnical, probabilistic, statistical, mathematical scientific principles and hybrid models.

کلیدواژه‌ها [English]

  • Retreat
  • Coastal Cliffs
  • Waves Energy
  • lithology
  • Retreat Models

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