Development of Finite Element Code for Analysis of Reinforced Concrete Slabs

A nonlinear finite element code has been developed to suite the analysis of normal and high strength concrete slabs. The computer program was built up using two computer languages, where the program interface part was coded in Visual-Basic language, while the main part was coded using FORTRAN language. A software called NLFEAS (Non-Linear Finite Element Analysis of Slabs) was developed to predicate and study the three dimensional response of reinforced concrete slabs of different grades, variables and boundary conditions under monotonically increasing loads. Using symmetry, a segment representing one quarter of the slab was considered in the analysis which was modeled using 20-node isoparametric brick elements and a 27-integration rule (3*3*3). Proper numerical material models for cracked concrete were incorporated in the analysis. The efficiency and accuracy of the developed code was verified through comparison with available test data, which showed good agreement. The effects of some finite element parameters such as mesh refinement and integral rule were also investigated

Change and Persistence, Proceedings of the International Conference, Tunis, 12-13 November 2013

This publication is based on the proceedings of an international conference entitled ‘Arab Revolutions and Beyond: Change and Persistence’, which was held in the framework of a multilateral project called ‘Challenges and Transformations in the Wake of the Arab Spring’ (2012-2014). The project is funded by the DAAD (German Academic Exchange Service) and based upon the longstanding partnership between Cairo University in Egypt and Freie Universität Berlin in Germany, specifically between the EuroMed Study Program at the Faculty of Economics and Political Sciences (FEPS) and the Centre for Middle Eastern and North African Politics at Otto-Suhr-Institute, Department for Political and Social Sciences. Dieser Sammelband ist ein Ergebnis der internationalen Tunis-Konferenz "Arab Revolutions and Beyond: Change and Persistence", die im Rahmen des multinationalen DAAD-Projekts "Challenges and Transformations in the Wake of the Arab Spring" im November 2013 stattfand. Neben Kolleg_innen der Universität Kairo, mit der bereits eine langjährige Partnerschaft besteht, sind auch Nachwuchsforscher_innen aus Tunesien, Libyen, Jordanien und weiteren Arabischen Staaten beteiligt. Das Projekt stellt sich den Herausforderungen, welche sich durch die politischen und sozialen Umbrüche in der Region für die akademische Bildung, v.a. in den Sozialwissenschaften ergeben haben. Hieraus soll ein produktiver Dialog über theoretische, methodische und thematische Felder der Sozialwissenschaften eröffnet werden, um die Strukturen von Forschung und Lehre dauerhaft zu verbessern.This publication is based on the proceedings of an international conference entitled ‘Arab Revolutions and Beyond: Change and Persistence’, which was held in the framework of a multilateral project called ‘Challenges and Transformations in the Wake of the Arab Spring’ (2012-2014). The project is funded by the DAAD (German Academic Exchange Service) and based upon the longstanding partnership between Cairo University in Egypt and Freie Universität Berlin in Germany, specifically between the EuroMed Study Program at the Faculty of Economics and Political Sciences (FEPS) and the Centre for Middle Eastern and North African Politics at Otto-Suhr-Institute, Department for Political and Social Sciences. The project addresses the challenges of current political and social transformations and their ramifications for higher education and the social sciences in Egypt and the region. The overarching objective of the project is to enter a productive dialogue on theories, methodologies and topics in social science research among Arab and German researchers. At the same time, we aim to improve teaching and research structures in the social sciences in a sustainable and efficient way. This will build students’ and teachers’ capacities on both shores of the Mediterranean and at the same time strengthen institutional efforts to promote the role of social sciences in the current transformations

On the fatigue response of a bonded repaired aerospace composite using thermography

Lock-in thermography was employed to investigate the repair efficiency of a bonded repaired aerospace composite subjected to step-wise cycling mechanical loading. The studied component (substrate) was artificially damaged with a 5 mm circular notch and subsequently repaired with a tapered bonded patch. Critical and sub-critical damage of the repaired component was monitored via thermography during 5 Hz tension–tension fatigue. The examination of the acquired thermographs enabled the identification of the patch debonding propagation as well as the quantification of the stress magnification at the patch ends and the locus of the circular notch. It was found that fatigue mechanical loading yields both thermoelastic and hysterestic phenomena with the latter being more prominent prior to the failure of the studied repaired component

Computational and experimental studies on the efficiency of Rosmarinus officinalis polyphenols as green corrosion inhibitors for XC48 steel in acidic medium

The performances of the extract obtained from Rosmarinus officinalis (RO) on the corrosion inhibition of XC48 steel is examined by mass loss method, electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM), potentiodynamic polarization (PDP), Fourier transform infrared (FTIR) spectroscopy and liquid chromatography–mass spectrometry (LC–MS). Investigations are performed in hydrochloric acid solution at 1 M concentration at different temperatures. Results show that the RO extract behaves as an inhibitor of mixed-type; in particular, the inhibition efficiency is augmented at greater concentration of the inhibitor and decreases with the rise of the temperature from 303 K to 333 K. The values of activation and free energy of inhibition reaction support the hypothesis of a mechanism of physisorption that is adequately described by the Langmuir equilibrium model. The retrieved outcomes are confirmed by SEM observations, which reveal that the adsorbed inhibitor molecules completely hinder the HCl attacks at the steel grain boundaries. Finally, quantum chemical calculations show that among the most abundant component detected in the RO extract, carnosic acid has a greater inhibitor potential with respect to carnosol