تقویت توان نگه‏داری پیچ و میخ در چندسازة چوبی با لایه های متقاطع (CLT) ساخته شده از صنوبر (Populus alba) با الیاف شیشه

نوع مقاله : مقاله پژوهشی

نویسندگان

1 گروه علوم و صنایع چوب و کاغذ، دانشکده منابع طبیعی، دانشگاه زابل، زابل، ایران.

2 گروه منابع طبیعی، دانشکده کشاورزی و منابع طبیعی، دانشگاه محقق اردبیلی، اردبیل، ایران.

10.22059/jfwp.2022.351422.1225

چکیده

در این مطالعه، تأثیر تعداد لایه ­های GFRP (پلیمر تقویت‌شده با الیاف شیشه) بر توان نگه‏داری پیچ چوب، پیچ سرمهره‌ای و میخ فولادی در چندسازة چوبی با لایه ­های متقاطع (CLT) ساخته شده از چوب صنوبر (Populus alba) مورد بررسی قرار گرفت. پانل­ های CLT با GFRP دو طرفه با وزن ویژه 600 گرم بر متر مربع با چهار نوع آرایش مختلف و با استفاده از چسب پلی­اورتان دو جزئی به‌مقدار 300 گرم بر متر مربع ساخته شدند. ابعاد نمونه ­های آزمونی 75×75 میلی‌متر و ضخامت آن‌ها بر حسب تعداد ­لایه ­ها متفاوت در نظر گرفته شد. نتایج تجزیه واریانس نشان داد که تأثیر تعداد لایه­­­ های GFRP بر توان نگهداری میخ و پیچ سرمهره ­ای از نظر آماری درصد معنی ­دار است (0/05>P). با افزایش تعداد لایه ­­های GFRP در CLT، توان نگهداری میخ، پیچ چوب و پیچ سرمهره­ای نسبت به نمونة شاهد به‌ترتیب 280/4، 29/2 و 83/3 درصد افزایش یافت. توان نگهداری پیچ سرمهره ­ای بیشتر از پیچ چوب و میخ بود. نتایج گروه­ بندی دانکن نشان داد که برای افزایش معنی­ دار توان نگهداری میخ، باید CLT را حداقل با سه لایة GFRP تقویت کرد. اما برای افزایش معنی­ دار توان نگهداری پیچ سرمهره ­ای، می­ توان CLT را با حداقل یک لایه و یا برای افزایش بیشتر با سه لایة GFRP تقویت کرد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Improved withdrawal capacity of nail and screw in cross-laminated timber (CLT) made of poplar (Populus alba) using glass fiber-reinforced polymer (GFRP)

نویسندگان [English]

  • Mohammad Arabi 1
  • Akbar Rostampour Haftkhan 2
1 Department of Wood Science and Technology, Faculty of Natural Resources, University of Zabol, Zabol, Iran.
2 Associate professor of Wood Science and Technology Department of Natural Resources, Faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili. Ardabil, Iran. Ardabil. Iran
چکیده [English]

In this study, we investigated the effects of glass fiber-reinforced polymers (GFRP) on the withdrawal capacity of wood, lag screws, and steel nails in cross-laminated timber (CLT) made from poplar (Populus alba). We reinforced CLTs with bidirectional GFRP wrap with a grammage of 600 g/m2. The specimens were 75 mm ×75 mm in length and width, and their thicknesses varied depending on the GFRP layers. We used two-component polyurethane glue at a rate of 300 g/m2. ANOVA results showed that the number of GFRP layers had a significant effect on the withdrawal resistance of nails and lag screws (P<0.05). By increasing the number of GFRP layers in CLT, the withdrawal resistance of the nails, wood screws, and lag screws increased by 280.4%, 29.2%, and 83.3%, respectively, compared to the control CLT samples. The withdrawal resistance of the lag screws was greater than that of the wooden screws and nails. Duncan's Multiple Range Test (MRT) results showed that CLT should be reinforced with at least three layers of GFRP to significantly increase the withdrawal resistance of nails. To significantly increase the withdrawal resistance of lag screws, CLT should be reinforced with at least one layer of GFRP or by three layers for further significant reinforcement.

کلیدواژه‌ها [English]

  • Glass Fiber Reinforced polymer
  • Joint performance
  • Lag screw
  • Steel nail
  • Wood screw
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