The provision of openings in serviceable reinforced concrete beams may result in a substantial decline in the beam's capacity and integrity, indicating the necessity of opening strengthening. The present study investigates the experimental response of reinforced concrete T-beams with multiple web-strengthened openings disposed in shear span to static and impact loads. Fourteen RC T-beams were tested in two groups, each of seven beams. The first group was tested under static loading up to failure, while the second group was tested under repeated impact loading until the width of shear cracks reached 0.3 mm. The residual static strengths of the beams subjected to impact loading were then determined. The test variables considered were: number of web openings, the method used to strengthen the member at openings and the height of drop during impact tests. All beams were simply supported with load applied at mid – span. Static results indicated that T-beams with four and six un-strengthened web circular openings whose diameter is 48% of the web depth have strength capacities less than those without openings by 30% and 41%, respectively. However, strengthening of webs results in an increase in the strength capacities ranging between 27% and 92%, depending on the type of strengthening. Impact results indicated that the beam with four openings did not show a remarkable increase in the maximum mid-span deflection compared with the solid beam, while that with six openings showed an increase in the maximum mid-span deflections by about 75% greater than the maximum mid-span deflection of the solid beam. Strengthening of specimens could overcome the increase in deflections.
The D.C electrical and thermoelectrically properties of randomly mixed isolator – electrolyte system as (Al/ PVC – LiF/Al) junction consisting of polyvinyl chloride (PVC)resin reinforced with Lithium Fluoride (LiF) powder were studied. A comparison is made the properties of (PVC) material with varying percentage of (LiF) powder (0%, 30%, 50%, 80%)to find out the effect of reinforcement of isolator material. The composites dissolving in 10ml form tettraHaedroflourn (THF) and Solution were the castled in Petri dish and Laved it dry in the air, The out coming Sample were disc - Like shape of a diameter of about 3cm and thickness reneged between (0.01- 0.018) cm . The composites dissolving in 10ml form tettraHaedroflourn (THF) a
... Show MoreA novel series of chitosan derivatives were synthesized via reaction of chitosan with carbonyl compounds and grafted it’s by with different amine compounds substituted hydrogen. The produced polymers were characterized by different analyses FTIR, 1HCNMR, XRD, DSC and TGA. Solubility in water as well as many solvent was investigated, antibacterial activity of chitosan and its derivatives against two types of bacteria E. coli and S. aureus was also investigated. The results showed that derivatives sort of have antibacterial activities against Esherichia coli (Gram negative) better than chitosan whilst compound IX has better antibacterial against Staphylococcus aureus (Gram positive). SEM analysis showed that increase of surface roughness wi
... Show MoreAim: The study designed to evaluate the Geno-protective effect of green tea extract against genotoxicity induced by metronidazole and tinidazole. Methods: Thirty-six mice were used, For each experiment, The animals divided into 6 groups: Group I- Negative control administered distilled water; Group II-Healthy mice treated with metronidazole alone, Group III- Healthy mice treated with tinidazole alone; Group IV- Healthy mice administered green tea extract alone Group V- Healthy mice treated with metronidazole, followed by green tea extract administration, Group VI- Healthy mice treated with tinidazole, followed by administration of green tea extract. Results: treatment with Tinidazole significantly increase total chromosomal aberration (0.18
... Show MoreBackground: Interleukine-2 is a multifunctional cytokine, considered a central regulator of host resistance against a variety of pathogens and has been recently demonstrated to exert an active role in the pathogenesis of periodontal diseases. The purpose of this study was to evaluate the effect of scaling and root planning on level of IL-2 in serum and saliva of patients with chronic generalized periodontitis, in relation to clinical parameters. Materials and Methods: A total of 50 subjects were enrolled, of which 25 had chronic generalized periodontitis and 25 periodontally healthy subjects as control. The clinical parameters included: gingival index, pocket probing depth, clinical attachment level and bleeding on probing. The level of
... Show MoreThe research aims to study Sabkha mineralogy to determine the mineral types, the nature of the precipitation, and the patterns of salt crystallization. Two Sabkhas in Abu Ghraib, west of Baghdad, were studied. It was found that the Sabkhas were formed in flat ponds from saturated solutions in a semi-arid to arid climate. Halite predominates, followed by anhydrite and gypsum as evaporite minerals. As for the minerals of the Sabkha soil, it consisted of feldspar, calcite, quartz, and dolomite, in addition to the clay minerals represented by kaolinite, illite, and chlorite. Needle forms, hopper shapes, dendritic crystals, and polygon shapes are the main crystallization patterns dominantly found in the Sabkhas. All these types of crysta
... Show MoreThe parasite was isolated from a stool sample, cultivated and maintained in vitro using Locke-egg medium (LEM) and Liver infusion agar medium (LIAM) . The culture was maintained for up to 21 months, and the best time to maintain the parasite was every 48 hours, although the growth in the culture media continued for 13 days without a maintenance. Additionally, no cyst formation was observed during cultivation of parasite in the two culture media. Although, was observe young cyst formed in LEM media were deletion of maintained. The diagnosis of bacteria growth in the culture media, bacterial content (Escherichia coli) was an dominance and essential requirement for a successful cultivation of Entamoeba histolytica in the two culture media.
A genetic algorithm model coupled with artificial neural network model was developed to find the optimal values of upstream, downstream cutoff lengths, length of floor and length of downstream protection required for a hydraulic structure. These were obtained for a given maximum difference head, depth of impervious layer and degree of anisotropy. The objective function to be minimized was the cost function with relative cost coefficients for the different dimensions obtained. Constraints used were those that satisfy a factor of safety of 2 against uplift pressure failure and 3 against piping failure.
Different cases reaching 1200 were modeled and analyzed using geo-studio modeling, with different values of input variables. The soil wa
This study examines the monthly mean diurnal variations of the ionospheric sporadic E (Es) layer’s critical frequency (
The present study was aimed to find out the role of humoral immunity in the pathogenesis of psoriasis. Complements C3, C4 and immunoglobulin IgE .The study included 55 Iraqi patients with psoriasis 30 (15 females ,15 males) were untreated with any drugs. The other patient group consisted of 25 (9 female and 16 male) treated with a biological treatment (infliximab) ,and 30 (13 males ,12 females) healthy control group. Blood sample were withdrawn (5) ml of venous blood for both patients and members of the control ,to conduct the Immunological tests to determine the quantitative for each of total IgE by using (ELISA) and C3,C4 by Single Radial Immunodiffuse (SIRD). The results showed significant increase in the level of probability (P <0.0
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