Deep beams are used in wide construction fields such as water tanks, foundations, and girders in multi-story buildings to provide certain areas free of columns. In practice it is quite often occurring to create web opening in deep beams to supply convenient passage of ventilation ducts, cable channels, gas and water pipes. Experimental studies of ten 10 deep beams were carried out, where two of them are control specimens without openings and eight with large web openings in the shear spans. The variables that have been adopted are the ratio of the shear span to the overall depth of the member cross-section, location and dimensions of the opening. Test results showed that there was a decrease in the load carrying capacity of deep beams with openings compared to the control deep beams. This reduction may reach 66% in particular cases. It is clear that, the position of opening in shear span has less effect on the performance of structural concrete deep beams at different serviceability stages. Only 11% increase in load capacity at failure was observed in specimens with openings adjacent to the interior edges of shear spans in comparison with specimens with openings at the center of shear span because the discontinuity of the load path is less. Also the midspan deflection at service load level of the reference beam in specimens with openings adjacent to interior edge of shear spans was less than the midspan deflection of reference specimens by 10% - 33%. Evaluating all these advantages facilitates to recommend, if it is very required, the creation of openings at the interior edges of shear spans of the structural concrete deep beams.
Roller compacted concrete (RCC) is a type of rigid pavement that is designed in a similar way to conventional concrete pavements reflecting its mode of failure. The thickness design of RCC pavements is based on keeping the flexural stresses and fatigue damage in the pavement caused by wheel loads within allowable limits. As in all jointed concrete pavements, there is a greater effect from loads placed along edges and less at interior locations in the pavement. Joints in RCC pavement are clearly critical areas and form weak points. RCC is typically constructed with saw-cut joints to prevent random cracking, improve the appearance of the pavement surface, and maintain the highest possible load transfer across the joints. This paper pr
... Show MoreBiodegradable polymers have garnered increasing attention as eco-friendly alternatives to conventional petroleum-derived plastics, which pose a global environmental challenge due to their difficult recycling and slow degradation. This study focuses on the preliminary evaluation of surface functional properties of chitosan films reinforced with TiO₂ or ZnO nanoparticles (NPs). These films were prepared at different loading ratios using the solution-casting method. Structural and morphological properties were characterized using FTIR and FESEM, while functional properties were evaluated by surface wettability, UV–Vis spectroscopy, thermogravimetric analysis and antibacterial activity testing. FTIR results showed significant changes in abs
... Show MoreThis paper presents a brief study undertaken for improving the performance of information and communication management of construction projects through investing in information and communication technologies (ICT). The work aims at first to investigate and diagnose the problems, challenges, weaknesses, and inefficiencies related to information and communication management in projects in the construction industry of Iraq. Studying the diagnosed matters and the different solutions of ICT to improve project management performance is following the investigation process. The research presents a technological system suggested to process a lot of the diagnosed problems, challenges, weakness, and inefficiencies of the construction projects and t
... Show MoreThis study aims to investigate the effect of changing skins material on the strength of sandwich plates with circular hole when subjected to mechanical loads. Theoretical, numerical and experimental analyses are done for sandwich plates with hole and with two face sheet materials. Theoretical analysis is performed by using sandwich plate theory which depends on the first order shear deformation theory for plates subjected to tension and bending separately. Finite element method was used to analyse numerically all cases by ANSYS program.
The sandwich plates were investigated experimentally under bending and buckling load separately. The relationship between stresses and the ratio of hole diameter to plate width (d/b) are built, by
... Show Moreتعتبر إزالة الكبريت بالأكسدة العميقة موضوعًا مهمًا لأبحاث التحفيز البيئي لإنتاج الديزل منخفض الكبريت.أحد العوامل المساعدة التي تم استخدامها مؤخرًا لإزالة مركبات الكبريت المقاوم من نموذج الديزل بالاكسدة هو بولي أوكسوميتالات من نوع كيجن. في هذا العمل, تم اختبار العامل المساعد من نوع كيجن TBAPW11O39 , نموذج الديزل, بيروكسيد الهيدروجين(H2O2) وسائل ايوني من نوع OMIM(PF6)) تحت ظروف تفاعل مختلفة. تم التقاط مركب الكبريت ث
... Show MoreThe fluorescence and absorption spectra of Fluoranthene dissolved in
cyclohexane and ethanol were studied and analyzed. The effect of the
concentration of this molecule and the polarity of the solvents on the spectral
shifts and on relative intensity has been investigated. A computational program
was written in order to convert the spectra from grapher to data. Some
photophysical parameters such as oscillator strength and quantum efficiency have
been calculated. Fluorescence quantum efficiency of Fluoranthene was measured
relative to Quinine Sulfate (QS) in 1N H2SO4. The obtained values were (0.5) in
cyclohexane and (0.45) in ethanol
Spatial data observed on a group of areal units is common in scientific applications. The usual hierarchical approach for modeling this kind of dataset is to introduce a spatial random effect with an autoregressive prior. However, the usual Markov chain Monte Carlo scheme for this hierarchical framework requires the spatial effects to be sampled from their full conditional posteriors one-by-one resulting in poor mixing. More importantly, it makes the model computationally inefficient for datasets with large number of units. In this article, we propose a Bayesian approach that uses the spectral structure of the adjacency to construct a low-rank expansion for modeling spatial dependence. We propose a pair of computationally efficient estimati
... Show MoreThe rapid rise in the use of artificially generated faces has significantly increased the risk of identity theft in biometric authentication systems. Modern facial recognition technologies are now vulnerable to sophisticated attacks using printed images, replayed videos, and highly realistic 3D masks. This creates an urgent need for advanced, reliable, and mobile-compatible fake face detection systems. Research indicates that while deep learning models have demonstrated strong performance in detecting artificially generated faces, deploying these models on consumer mobile devices remains challenging due to limitations in computing power, memory, privacy, and processing speed. This paper highlights several key challenges: (1) optimiz
... Show MoreThe rapid rise in the use of artificially generated faces has significantly increased the risk of identity theft in biometric authentication systems. Modern facial recognition technologies are now vulnerable to sophisticated attacks using printed images, replayed videos, and highly realistic 3D masks. This creates an urgent need for advanced, reliable, and mobile-compatible fake face detection systems. Research indicates that while deep learning models have demonstrated strong performance in detecting artificially generated faces, deploying these models on consumer mobile devices remains challenging due to limitations in computing power, memory, privacy, and processing speed. This paper highlights several key challenges: (1) optimiz
... Show More