الفهرس 
Chapter.1 INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The basalt fiber plates reinforced with various types of expanded steel meshes were developed with high strength, crack resistance, high ductility and energy absorption properties which might be useful for dynamic applications. Five series of plates were casted and tested under four different loading conditions. The dynamic responses such as: frequency, mode shape and damping factor were extensively investigated using FFT analyzer. Experimental modal analysis was carried out using B&K data acquisition type (3160-A-042) analyzer equipped with B&K Pulse 17.1 software. The experimental analysis and finite element technique were utilized to study the effect of open steel mesh configuration, basalt fiber ratio and boundary fixations on dynamic characteristics of concrete structures. In the present thesis, mathematical modeling based on finite element method (FEM) has been established. The validation of these models and the dynamic characterization of materials have been examined. The effect of boundary conditions and basalt fiber composite properties such as, elastic modules, volume fraction and open mesh area on the frequency and damping factor values has been studied. The mathematical finite element models (FEM) are developed to compute the Eigen-nature for reinforced concrete structures. Modified mechanical parameters are introduced to increase the accuracy of developed model.
The experimental analysis and finite element technique were utilized to study the effect of network configurations and boundary characteristics
In addition, the investigated basalt fiber plates were tested in the high frequency range (up to 140 kHz) through ultrasonic attenuation technique. For this purpose, an experimental setup was designed and constructed to measure dynamic elastic modulus, phase velocity and damping attenuation. The effect of mesh-layer de-bonding on the dynamic characteristics (natural frequency and damping ratio) was investigated. Damage was detected using vibration measurements and identified by comparing signals in higher frequency ranges before and after damage.
The main conclusions were arrived at i) The open mesh percentage and the ratio of volume fraction play an important role for controlling the dynamic behavior of dynamic analysis of concrete structures reinforced with composite materials. ii) The mutual influences of basalt fiber volume, open mesh area, boundary conditions and vibration mode are significant on the damping capacity.