This paper presents an experimental study for strengthening existing columns against axial compressive loads. The objective of this work is to study the behavior of concrete square columns strengthening with circulation technique. In Iraq, there are significantly more reinforced rectangular and square columns than reinforced circular columns in reinforced concrete buildings. Moreover, early research studies indicated that strengthening of rectangular or square columns using wraps of CFRP (Carbon Fiber Reinforced Polymer) provided rather little enhancement to their load-carrying capacity. In this paper, shape modification technique was performed to modify the shape (cross section) of the columns from square columns into circular columns. Shape modification technique is also called circularization technique because the cross section is modified from square into circular cross section. Then, the circularized columns were wrapped with CFRP wraps. Shape modification is the strengthening method adopted in this paper as a mean to strengthen existing square columns. Columns studied in this paper are short columns with square sections as a special case of rectangular columns. Columns in this study are plain concrete columns (having concrete strength of = 24.41 MPa) with no internal steel reinforcement. The aim of this research is to study experimentally the behavior of circularized concrete square columns confined with CFRP wraps. Then, for better understanding, the results were compared with another, more widely used, strengthening technique which is the direct wrapping of square columns with CFRP wraps. Thus, investigating experimentally the effectiveness of the two aforementioned strengthening techniques in increasing the load-carrying capacity and ductility of the existing concrete columns. The methodology of this research is that six plain concrete short square columns were casted. These six columns were exerted to compressive pressure using concrete testing machine. These six columns were divided into three groups, each group consisted of 2 columns. The three groups were classified as follows: first group (titled L0) consisted of two square columns which were not strengthened by any method, second group (titled L1) consisted of two square columns confined by one layer of CFRP wraps, finally, the third group (titled LC1) consisted of two circularized square columns confined by one layer of CFRP wraps.Experimental results showed that load bearing capacity and ductility of square columns have been significantly enhanced. Test results showed that shape modification technique (columns LC1) produced enhancement in load carrying capacity about 167.8 % of the original non-strengthened columns (columns L0). Furthermore, square columns wrapped by one layer of CFRP wraps (columns L1) produced enhancement in load carrying capacity about 56.1% of the original non-strengthened columns (columns L0). As such, it was evident that circularization technique resulted in enhancement in load carrying capacity far more than the enhancement obtained from wrapping the square columns with CFRP wraps.
Background: It is well-known that silicon oil (SO) injection into the vitreous cavity after pars plana vitrectomy is usually associated with high intraocular pressure.
Objectives: To determine the influence of silicon oil (SO) removal on IOP level after pars plana vitrectomy for spontaneous rhegmatogenous retinal detachment (RRD)
Subjects and Methods: A prospective study was conducted at Ibn Al-Haitham eye teaching hospital, Baghdad- Iraq. Intraocular pressure (IOP) was measured pre and post SO removal in patients who have underwent retinal detachment surgery with SO injection of 1000 centistokes (cSt) viscosity. Baseline IOP was measured for all the patient before the SO
... Show MoreIntroduction: Nowadays, the prevalence of Musculoskeletal Discomforts (MSD) is increasing in the world. As treatment, usually surgery or physiotherapyare recommended, but they are expensive and may cause side effects. Apracticalcourse of treatment without negative side effects and with permanent positive effects is lacking. Objective: To suggest a practical course of treatment, introduced by a licensed Yoga coach who is experienced in this field, and through thatto shed a light on yoga as treatment for MSD. The hypothesis is that yoga may decrease the pain among individuals with MSD. Methods: This hypothesis is presented based on the practical techniques used in Yoga including body relaxation and breathing awareness (2 minutes & 3 minutes r
... Show MoreThe current research aims to train students to take benefit of their studies to analyze and taste the artistic works as one of the most important components of the academic structure for students specializing in visual arts; then to activate this during training them the methods of teaching. Consequently, the capabilities of mind maps were employed as a tool that would be through freeing each student to analyze a model of artistic work and think about his analytical principles according to what he knows. Then, a start-up with a new stage revolves around the possibility of transforming this analysis into a teaching style by thinking about how the student would do. The same person who undertook the technical analysis should offer this work
... Show MoreThe subject of social capital is of great importance, as it provides an analytical framework for researchers interested in understanding the impact of the Internet on many dimensions of human and social life. And because social networking sites have infiltrated societies and produced new variables at the level of human and social communication, this study came to examine the relationship between the use of the social networking site Facebook and the accumulation of social capital among a sample of University of Algeria 3 students, by researching the variables of intensity of use and patterns of use as independent variables and their relationship to social capital. The results of the field study revealed a strong relationship between the
... Show MoreBones were recorded in the skeleton of some species of Iraqi turtle Mauremys rivulata; the objectives of this study came in light of current conditions, environmental developments, talents and techniques of biological studies taking place in the country, need for an anatomy guide in river turtles of Iraqi species, to identify all kinds of similarities and differences with their preaching, this work or study has become written in response to those modern needs. It is designed to be one of the resources for those interested in biological studies, beginners or professionals, and veterinarians, distinguishing them from marine and global species. Turtles were dissected in the laboratories of the Research Center and Museum of Natural Hist
... Show MoreThe purpose of this paper to discriminate between the poetic poems of each poet depending on the characteristics and attribute of the Arabic letters. Four categories used for the Arabic letters, letters frequency have been included in a multidimensional contingency table and each dimension has two or more levels, then contingency coefficient calculated.
The paper sample consists of six poets from different historical ages, and each poet has five poems. The method was programmed using the MATLAB program, the efficiency of the proposed method is 53% for the whole sample, and between 90% and 95% for each poet's poems.
Aggregate production planning (APP) is one of the most significant and complicated problems in production planning and aim to set overall production levels for each product category to meet fluctuating or uncertain demand in future. and to set decision concerning hiring, firing, overtime, subcontract, carrying inventory level. In this paper, we present a simulated annealing (SA) for multi-objective linear programming to solve APP. SA is considered to be a good tool for imprecise optimization problems. The proposed model minimizes total production and workforce costs. In this study, the proposed SA is compared with particle swarm optimization (PSO). The results show that the proposed SA is effective in reducing total production costs and req
... Show MoreKE Sharquie, AA Noaimi, HA Al-Mudaris, Journal of Drugs in Dermatology: JDD, 2013 - Cited by 22
Background: techniques of image analysis have been used extensively to minimize interobserver variation of immunohistochemical scoring, yet; image acquisition procedures are often demanding, expensive and laborious. This study aims to assess the validity of image analysis to predict human observer’s score with a simplified image acquisition technique. Materials and methods: formalin fixed- paraffin embedded tissue sections for ameloblastomas and basal cell carcinomas were immunohistochemically stained with monoclonal antibodies to MMP-2 and MMP-9. The extent of antibody positivity was quantified using Imagej® based application on low power photomicrographs obtained with a conventional camera. Results of the software were employed
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