تکنیک‌های ارزیابی ظرفیت باربری پی سطحی زبر با روش خطوط مشخصه‌ی تنش

نوع مقاله : مقاله ترویجی

نویسندگان

1 گروه مهندسی عمران، واحد تهران جنوب، دانشگاه آزاد اسلامی، تهران، ایران

2 پژوهشکده مهندسی ژئوتکنیک، پژوهشگاه بین المللی زلزله شناسی و مهندسی زلزله، تهران، ایران

چکیده

برآورد ظرفیت باربری پی­های سطحی همواره مورد نیاز مهندسین بوده است. روش مشخصه­های تنش برای حل مسائل ظرفیت باربری پی­های مستقر بر فضای نیم‌بی­نهایت به دلیل سادگی، سرعت در انجام محاسبات و عدم نیاز به مش­بندی و مدل­های رفتاری پیچیده­ی خاک، تکنیکی کارآمد و مؤثر است. در نوشتار حاضر، ابتدا فرمول­بندی ریاضی روش خطوط مشخصه­ی تنش به‌اختصار تشریح شده است. نحوه­ی به‌کارگیری آن در ارزیابی ظرفیت باربری پی­های زبر و تکنیک­های مختلف حل مسئله‌ی زبری بررسی شده است. سپس، چگونگی در نظر گرفتن یکنواختی یا غیریکنواختی شیب فشار تماس وارد بر کف پی و تأثیر آن بر ضرایب ظرفیت باربری پی­ها مورد بحث و بررسی قرار گرفته است. اثرات ناشی از نحوه­ی ملحوظ نمودن زبری به روش­های مختلف بر این ضرایب سه­گانه با یکدیگر مقایسه شده است. در نهایت، به چالش‌های جدید و مهم پیش رو در استفاده از روش مشخصه‌‌های تنش در بررسی اثرات زبری بر ظرفیت باربری پی پرداخته شده است.

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