بررسی اثر دمای بستر و اپوکسی در هنگام نصب بر روی مقاومت چسبندگی ورق‌های GFRP با استفاده از دو آزمون جدا کردن با کشش (Pull-off) و با پیچش (Twist-off)

مهندسی عمران فردوسی

مقاله 8، دوره 35، شماره 1 - شماره پیاپی 37، خرداد 1401، صفحه 13-30   

نوع مقاله: مقاله پژوهشی

شناسه دیجیتال (DOI): 10.22067/jfcei.2022.74568.1111

نویسندگان

پیمان ایمانی جاجرمی¹؛ محمدرضا توکلی زاده^{* 2}؛ عباس یوسفی³

¹دانشکده مهندسی دانشگاه فردوسی مشهد.

²دانشکده مهندسی، دانشگاه فردوسی مشهد

³لعاب مشهد - پرطاووس

چکیده

 استفاده از ورق‌های پلیمر مسلح با الیاف (FRP) به‌دلیل مزایای بسیار زیاد آن‌ها به‌عنوان یکی از پر کاربردترین مصالح به‌سازی سازه‌های بتنی شناخته ‌شده‌است. هدف از انجام این پژوهش، بررسی اثر دمای سطح بستر و هم‌چنین اپوکسی در بازۀ 5 تا 80 درجۀ سانتی‌گراد برروی مقاومت چسبندگی ورق‌های FRP با الیاف شیشه‌ای به بستر پایه‌سیمانی است. به همین منظور، از دو آزمون نیمه‌مخرب جدا کردن تحت کشش (Pull-off Test: POT) و جدا کردن تحت پیچش (Twist-off Test: TOT) بهره‌ گرفته شده‌است. نتیجه‌های این پژوهش براساس تحلیل و بررسی داده‌های 288 آزمونه از 32 نمونۀ ساخته‌شده گزارش شده‌است. به‌منظور درک بهتر اثر دمای سطح بستر و چسب اپوکسی و هم‌چنین برهم‌کنش آن‌ها، برروی مقاومت چسبندگی ورق‌های GFRP، نتایج به‌دست‌آمده بااستفاده از نرم‌افزار SPSS مورد تحلیل واریانس نیز (ANOVA) قرار گرفت. براساس این پژوهش، بیشترین مقاومت چسبندگی مربوط به نمونه‌هایی با دمای سطحی و اپوکسی 50 درجۀ سانتی‌گراد بود که نسبت‌به نمونۀ مبنا (دمای سطحی و اپوکسی 25 درجۀ سانتی‌گراد)، برای روش POT و TOT به‌ترتیب، 36 و 24 درصد افزایش را نشان ‌داد. هم‌چنین، نتیجه‌ها نشان داد، اثر منفی دمای سطح بستر را می‌توان تاحدی با افزایش دمای اپوکسی جبران کرد. افزون بر این، تحلیل درون‌یابی غیرخطی انجام‌شده برروی نتیجه‌ها حاکی از وجود یک رابطۀ نمایی بین مقاومت‌های چسبندگی به‌دست‌آمده از دو روش POT و TOT بود.

کلیدواژه‌ها

مقاومت چسبندگی؛ دمای سطح بستر؛ دمای اپوکسی؛ Pull-off؛ Twist-off

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