The effect of fiber pre-tension on the static and dynamic behavior of composite plates

العناوين الأخرى

تأثير الشد المسبق للألياف على السلوك الستاتيكي و الديناميكي لصفائح مواد متراكبة

مقدم أطروحة جامعية

Yasir, Ali Sadiq

مشرف أطروحة جامعية

Nacy, Sumr Matti
Abd al-Nur, Sabah

أعضاء اللجنة

Ataiwi, Ali H.
al-Sadi, Munir H.
al-Fattal, Zafir Sadiq
Yusuf, Albert E.
Tawfiq, Muwaffaq A.

الجامعة

الجامعة التكنولوجية

الكلية

-

القسم الأكاديمي

قسم الهندسة الميكانيكية

دولة الجامعة

العراق

الدرجة العلمية

دكتوراه

تاريخ الدرجة العلمية

2007

الملخص الإنجليزي

The increase in using the composite materials in engineering applications , make it necessary to improve composite properties to make it able to do its work.

One of the methods to improve the composite properties is Fibers Pre-Stressing during room temperature curing process .

In this thesis Epoxy resin was used as matrix and E-glass fibers to manufacture the samples that were tested by tensile, bending , and single fiber pull-out tests .

The prestressing range between (2-20MPa) are subjected to the fibers at room temperature curing process .

The finite element modeling was used to compare with the experimental results.

Dynamic model was achieved using finite element to get the natural frequencies and modes shape and compare the results with analytical solution by using JACOBI iteration method that was solved by using FORTRAN program .

The results show that the tensile strength and maximum tensile strain of composite plates increased due to the pre-stressing .

The stress strain curves for samples show a high increase in stress as compared to a little increase in strain .

The modulus of elasticity (Young's Modulus) increased due to the prestressing process , also the stiffness of composite increased due to the increasing of pre-stressing level.

The interfacial shear stress decreased due to fibers pre-stress and the reduction ratio was inversely proportional to the applied load that ranging between (1kN – 5.5kN).

The maximum bending stress and maximum shear stress due to bending increased due to the increase in the pre-stressing levels .

II Also the bending modulus increased due to the increasing in pre-stressing levels .The bending load-deflection ratio(Bending Stiffness) increased also due to the pre-stressing for the fibers .

The single fiber pull-out test results show that the debond shear stress was increased due to the pre-stressing for the single fiber .

For the dynamic analysis four models with different types of supports ,and the results show that the Natural Frequencies increased due to the pre-stressing for the fibers and the modes shape show that the models were deformed in Z , x , and y directions for most of the modes .

التخصصات الرئيسية

الهندسة الميكانيكية

عدد الصفحات

150

قائمة المحتويات

• APA
• MLA
• AMA

لغة النص

الإنجليزية

نوع البيانات

رسائل جامعية

رقم السجل

BIM-749816