ارزیابی سرعت موج برشی در خاک‌های دانه‌ای با استفاده از المان‌های خمشی و ستون تشدید

نوع مقاله : Articles

نویسندگان

1 گروه مهندسی عمران، واحد نجف‌آباد، دانشگاه آزاد اسلامی، نجف‌آباد

2 گروه مهندسی عمران، دانشکده فنی، دانشگاه تهران، تهران

چکیده

سرعت موج برشی در خاک­ها یکی از پارامترهای مهم در مطالعات دینامیکی خاک­ها محسوب می­شود. این پارامتر در نمونه­های المانی خاک از طریق آزمایش­های المانی یا در محل از طریق آزمایش­های ژئوفیزیک قابل ارزیابی است. از جمله روش­های پرکاربرد در آزمایشگاه جهت تخمین سرعت موج برشی در خاک­ها استفاده از المان­های خمشی و آزمایش ستون تشدید است. در این مقاله با مقایسه نتایج به‌دست‌آمده از المان­های خمشی و ستون تشدید، مقادیر فرکانس مناسب در آزمایش المان خمشی در خاک­های دانه­ای به دست آمده است. از طرف دیگر تأثیر نسبت منافذ، تنش همه‌جانبه و درصد شن بر روی سرعت موج برشی مورد بحث قرار گرفته است. نتایج نشان می­دهد که با کاهش نسبت منافذ یا افزایش تنش همه‌جانبه، سرعت موج برشی به­صورت غیرخطی افزایش می­یابد. از طرف دیگر با افزایش مقدار شن  تا 50 درصد به ماسه میزبان، سرعت موج برشی افزایش یافته و بعد از آن با افزایش شن، سرعت موج برشی کاهش می­یابد.

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