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 diamete
r 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.
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
l samples were exposed to destructive acid
effect (nitric acid, sulphuric acid ) of a ratio 3% and PH ≤ 4.
مازالت طرائق اختبار المقاومات للخرسانة بالطرق اللاتخريبية تعدُّ طرقاً غير مباشرة. و نظراً لعدم
وجود مفهوم واضح و عام و ثابت لمقاومة الخرسانة فإن طريقة العينات الأسطوانية أو المكعبية تعد
أيضاً طريقة غير مباشرة لقياس المقاومة الهندسية، و انطلاقاً من
ذلك يتخصص هذا العمل كمحاولة
علمية تجريبية جادة لتطوير العلاقات الحسابية للحصول على أدنى و أصغر خطأ ممكن للقراءات
باختبار المطرقة الخرسانية الارتدادية مع مقارنة حقيقية واقعية لمقاومات الخرسانة ذاتها من خلال
اختبار عينات خرسانية مكعبية من منشآت منفذة و مراقبة من قبلنا و بشكل موازٍ.
The physical properties of gravel play an important role on the
quality of concrete industry in local workshops. Because they
constitute a main role in various concrete mix design. It's
necessary to understand the importance of the physical proper
ties
of gravel and It's improving role in the concrete mixes.
This research aimed to study the role of the properties of gravel
on the concrete mixes manufacture.
This article, will look at the structural development of the high
rise buildings and the factors that led to these developments, and so out
of the basic structural systems, even new classifications for
constructional systems (internal systems external systems), as well as
most construction systems deployed use.
