حاليا يتم اسهتلاك مئات الأطنان من الإطارات سنويا مما يستدعي التخلص بكفاءة من هذه الكميات من الإطارات المستهلكة و تطوير وسائل لتحويلها الى مواد مفيدة. في سورية فقط تقدر كمية الأسلاك الناتجة من الإطارات سنويا بحوالي6000 طناً.
يتناول هذا البحث تأثير اضافة الألياف الفولاذية المستخرجة من الإطارات المستهلكة للسيارات على مقاومة الضغط للخرسانة. تم تحضير عينات لثلاثة خلطات من الخرسانة بعيارات اسمنت 300-350-400 كغ/م3 و أضيفت الألياف الفولاذية بقطر 0.8 مم بنسب حجمية تساوي 0.5 - 1 - 1.5% و بأطوال 30 - 40 - 60 مم بالاضافة الى عينات مرجعية بدون الياف.
بينت النتائج تحسنا في سلوك الخرسانة على المتانه و سلوك البيتون في مرحلة مابعد التشقق بالإضافة الى زيادة في مقاومتها على الضغط مما يمكن من استعمالها في تطبيقات هندسية عديدة مثل رصف المهابط في المطارات و أرضيات المعامل و المنشآت المائية نظرا لمقاومة هذه الخرسانة للتآكل بسبب جريان الماء و غير ها من التطبيقات.
Recently worldwide researches have been devoted to the use of steel fibers recovered from used tires in concrete. In Syria the amount of recovered steel from used tires is estimated about 6000 tons/year.
For this purpose a bead wire having a diameter of 0.8 mm from burnt tires was extracted and used. Three mixes with cement content 300- 350 -400kg/m3 were produced incorporating three different volumes of fiber 0.5%, 1.0%, and 1.5% and three different length 30-40-60 mm. The concrete obtained by adding these fibers evidenced a satisfactory improvement of the fragile matrix mostly in terms of toughness and post cracking behavior On the other hand it was improvements in compressive strength by steel fiber inclusion the interesting results confirm the promising application of concrete reinforced with steel fibers extracted from used tires in aircraft pavement hydraulic structures and ground slab in fabrics.
References used
ACI Committee 544, Design Considerations for Steel Fiber Reinforced Concrete, ACI 544.4R-88
ACI Committee 544, State-of-The-Art Report on Fiber Reinforced Concrete, ACI 544 1.R-96
AIELLO; LEONE :steel fibers from waste tires as reinforcement in concrete:a mechanical characterization. department of innovation engineering, university ofsalento, via monteroni, 73100, lecce, italy
BANTHIA & TROTTIER. Test Methods for Flexural Toughness Characterization of Fiber Reinforced Concrete: Some Concerns and a Proposition no. ACI Materials Journal, V. 92 No. 1, January-February 1995.p.1-10
BENCARDINO, F., RIZZUTI, L., SPADEA, G. Experimental tests vs. theoretical modeling for FRC in compression. In Proc. 6th Int. Conf. on Fracture Mechanics of Concrete and Concrete Structures - FraMCoS-6, Catania, Italy, 2007
This research presents an experimental study about the effect of steel fibers on the
main variables of stress- strain curve for high strength concrete on simple compression,
which are: shape of stress- strain curve, ductility factor, energy absorpt
Thepaper studies the mechanical properties ofsteel fibers reinforced lightweight
concrete.This kind of concrete is produced by usingscoria aggregateswhich can be found
abundantly in Syria. Thelightweight concrete mixeswere designed for three differ
the purpose of this research was to concentrate on this subject, where
four types of concrete mixes of the same shape were prepared (Abrams
settlement about 20 cm), but the cement content and compression strength
in each mixture were different, al
This research studies the effect of the addition of polypropylene
fibers (PF) on the properties of the swelling clayey soil. The effect
of PF on the shear strength of the clayey soil has been studied
and the results show that adding PF, up to spec
This paper presents the shear behavior of lightweight concrete beams
without shear reinforcement produced by scoria aggregates. A total of nine
beams were tested under four-point loads, including three lightweight
concrete beams without steel fibers and six steel fiber reinforced
lightweight concrete beams.