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Fiber reinforced plastic (FRP) jacketing has emerged as an effective way to retrofit concrete columns in recent years. The existing experimental work on FRP confined concrete column is mainly concentrated on concrete columns under concentric loading. Therefore, this research involves the study of nonlinear finite element analysis of FRP confined square and rectangular R.C. columns under both axial compressive and lateral loads. Lateral load was taken as a ratio of the axial compressive loads "H/ Pc". The effects of the FRP layer number, concrete compressive strength, percentage of main steel, rectangularity of columns and various ratios of lateral loads to centric load on FRP confined concrete columns were investigated theoretically. The results of this work were compared with previous work [1] considered the behavior of square and rectangular columns confined with CFRP under centric loads. All studied columns were modeled using the nonlinear finite element analysis. The main variables studied were the cross-section shape of the column “R”, concrete grade “C”, the percentage of area of the main longitudinal steel “As%” and the number of layers of CFRP sheet “NL”. The FEM results indicated that R.C. columns externally wrapped with CFRP sheet showed a significant improvement in both capacity and ductility.

Fiber reinforced plastic (FRP) jacketing has emerged as an effective way to retrofit concrete columns in recent years. The existing experimental work on FRP confined concrete column is mainly concentrated on concrete columns under concentric loading. Therefore, this research involves the study of nonlinear finite element analysis of FRP confined square and rectangular R.C. columns under both axial compressive and lateral loads. Lateral load was taken as a ratio of the axial compressive loads "H/ Pc". The effects of the FRP layer number, concrete compressive strength, percentage of main steel, rectangularity of columns and various ratios of lateral loads to centric load on FRP confined concrete columns were investigated theoretically. The results of this work were compared with previous work [1] considered the behavior of square and rectangular columns confined with CFRP under centric loads. All studied columns were modeled using the nonlinear finite element analysis. The main variables studied were the cross-section shape of the column "R", concrete grade "C", the percentage of area of the main longitudinal steel "As%" and the number of layers of CFRP sheet "NL". The FEM results indicated that R.C. columns externally wrapped with CFRP sheet showed a significant improvement in both capacity and ductility.

The existing experimental work on FRP confined concrete column is mainly concentrated on concrete columns under co centric loading in recent years. Therefore this research involves the study of nonlinear FE analysis of FRP confined square and rectangular R.C. columns under both axial compressive and lateral loads. Lateral load was taken as a ratio of the axial compressive loads "H/ Pc". The results of this work were compared with previous work (Soghair, H.M. et al. 2004) considered the behavior of square and rectangular columns confined with CFRP under centric loads. All studied columns were modeled using the nonlinear finite element analysis. The main variables studied were the cross-section shape of the column "R", concrete grade "C", the percentage of area of the main longitudinal steel "As%" and the number of layers of CFRP sheet "NE'. The FEM results indicated that R.C. columns externally wrapped with CFRP sheet showed a significant improvement in both capacity and ductility.

Currently, there is no general agreement on a theory describing the response of reinforced concrete members without web reinforcement. Many structural systems are usually performed using empirical or semi-empirical expressions provided by codes of practice that do not consider the influence of many governing parameters. In this paper, a comparison between values of current experimental shear strength and those of various international design approaches like ACI, Canadian, FIB and the method proposed by Sudheer, Zararis ,Zsutty ,Shah ,Bazant and Russo. Eighteen simple span high strength reinforced concrete “HSRC” deep beams without web reinforcement were tested and analyzed under two static point loads at mid-span of the beam to examine the contribution of various parameters on the shear capacity of HSRC beams. The main studied parameters are f‟cu=50 MPa, three values of tension reinforcement-ρ%-(0.73%,1.21% &1.83%) and shear span to effective depth ratio-a/d-( 2,1.5 &1). As a conclusion of this paper, ACI and FIB code provisions for shear in HSC are safe for use with the exception that CSA should be used with care. Despite numerous studies, there is still a need to develop a clear understanding of the shear behavior of HSC beams without web reinforcement. Therefore, this experimental program was arranged to evaluate the shear behavior and to increase the shear database on HSRC deep beams.

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ABSTRACT Social networks have become one of our daily life activities not only in socializing but in e-commerce, e-learning, and politics. However, they have more effect on the youth generation all over the world, specifically in the Middle East. Arabic slang language is widely used on social networks more than classical Arabic since most of the users of social networks are young-mid age. However, Arabic slang language suffers from the new expressive (opinion) words and idioms as well as the unstructured format. Mining ...

ABSTRACT Social networks have become one of our daily life activities not only in socializing but in e-commerce, e-learning, and politics. However, they have more effect on the youth generation all over the world, specifically in the Middle East. Arabic slang language is widely used on social networks more than classical Arabic since most of the users of social networks are young-mid age. However, Arabic slang language suffers from the new expressive (opinion) words and idioms as well as the unstructured format. Mining ...

We modified a previously reported computer-assisted sperm analysis (CASA) plugin for Image-J to enable analyzing motion of sperm cells in microfluidic environments. Microfluidics is increasingly being used in sperm-related applications such as sperm selection, IVF, and sperm motion behavior. Current CASA systems are not capable of analyzing motion of sperm cells in microfluidic devices where both sperm cells and the liquid itself are constantly moving, contrary to the conventional situation of sperm cells moving in a stationary liquid. We resolved this deficiency in the modified plugin reported here and built an image processing pipeline to enhance object detection, which increased CASA accuracy considerably. More importantly, particle tracking was improved and modified to accommodate sperm cells going out of focus for short periods during swimming on the same track. This last feature is particularly important in microfluidics where height of the microchannel is larger than that of CASA custom chambers to avoid channel blockage; this increased height causes sperm cells to frequently come in and out of focus. New parameters were introduced to allow studying new aspects of sperm motion behavior such as rheotaxis and wall tracking. The new plugin was able to detect and analyze motion of human, bull, and chicken sperm. A preliminary study using this tool agreed well with previously reported studies on rheotaxis and wall tracking behavior of sperm.