This paper presents a study (experimentally) for strengthening reinforced concrete (RC) beams with Near-Surface-Mounted (NSM) technique. The use of this technique with CFRP strips or rebars is an efficient technology for increasing the strength for flexure and shear or for repairing damaged reinforced concrete (RC) members. The objective of this research is to study, experimentally, RC beams either repaired or strengthened with NSM CFRP strips and follow their flexural behavior and failure modes. NSM-CFRP strips were used to strengthen three RC beam specimens, one of them was initially strengthened and tested up to failure. Four beam specimens have been initially subjected to preloading to 50% and 80% of ultimate load. Two of the specimens were either repaired or strengthened with NSM-CFRP strips. All the repaired/strengthened pre-damaged beams have been tested up to failure by using compression-testing machine. An appropriate-scale model was adopted. All the specimens have a cross-sectional dimension of 150 mm with an effective span of 110 mm. Depends on the experimental results, a better performance of the strengthened concrete specimens was obtained in both strength and serviceability. As a comparison with the control beam specimen, all the repaired specimens show a very good increase of about 40% in the load-carrying capacity and a high improvement in resistance to cracking of about 120% in NSM. On the other hand, the test results of NSM CFRP-strengthened concrete specimens with a preloading of 50% and 80% of the ultimate load show an increase of about 9% to 20% in the load-carrying capacity, for 50% and 80% pre-loading, respectively an improvement in deflection of about 2% to 27% in NSM, for 80% and 50% pre-loading, respectively.
Steel–concrete–steel (SCS) structural systems have economic and structural advantages over traditional reinforced concrete; thus, they have been widely used. The performance of concrete made from recycled rubber aggregate from scrap tires has been evaluated since the early 1990s. The use of rubberized concrete in structural construction remains necessary because of its high impact resistance, increases ductility, and produces a lightweight concrete; therefore, it adds such important properties to SCS members. In this research, the use of different concrete core materials in SCS was examined. Twelve SCS specimens were subjected to push-out monotonic loading for inspecting their mechanical performance. One specimen was constructed from co
... Show MoreThere is an interesting potential for the use of GFRP-pultruded profiles in hybrid GFRP-concrete structural elements, either for new constructions or for the rehabilitation of existing structures. This paper provides experimental and numerical investigations on the flexural performance of reinforced concrete (RC) specimens composite with encased pultruded GFRP I-sections. Five simply supported composite beams were tested in this experimental program to investigate the static flexural behavior of encased GFRP beams with high-strength concrete. Besides, the effect of using shear studs to improve the composite interaction between the GFRP beam and concrete as well as the effect of web stiffeners of GFRP were explored. Encasing the GFRP
... Show MoreBecause of the tremendous changes in the business environment and significant growth in living standards, increased demand for services in general and about the realized practitioners in the field of service that traditional marketing strategies and models administrative based solutions to mono as the price alone does not lead to the desired outcomes with customers and even organizations as it does not apply always for the manufacture of their services unique . therefore , the need to learn marketing service order and a clear and critical to avoid failures in service and the marketing document to knowledge would avoid the organization that the failure in the delivery of service and enhances the desired response to fix it in a tim
... Show MoreRespiratory syncytial virus (RSV) is an important cause of respiratory infection among children and infants globally. The first line of the immune response against this virus is neutrophils, macrophages, and innate lymphoid cells. Antigen‑presenting cells such as dendritic cells which present the viral antigen to T lymphocytes that mediate viral clearance by T cytotoxic cells and initiate systemic lymphopenia. Humoral immunity will also be stimulated through B‑cell‑stimulating factors derived from epithelial cells of the respiratory tract that play an important factor in antibody production and induction memory to reinfection through IgG and IgA protective antibodies that are useful in vaccine production.
Shade in house gardens is one of the problems that hinder the growth of lawn and its distribution in the soil, where the types of lawns differ in their durability and adaptation to shade. The research aims to know the resistance of some species of lawn plants to shade and to know the appropriate fertilization procedures that can be followed to reduce the negative effects. The study was conducted in the Amiriya district of Baghdad in a house garden. Three varieties of lawn plants Bermuda, Gazon, and Trifoglio were planted. Five fertilization treatments (contained N and P elements) and the control were used. The sunlight density with the temperature of the study field locations were estimated using the AMT-300 and the vegetation coverage perc
... Show MoreTo explore the potential for in vitro rapid regeneration of Spanish dagger (Yucca gloriosa 'Variegata'), different concentrations of 6-Benzyladenine (BA), 1-naphthaleneacetic acid (NAA) and combinations of both were evaluated for callus induction initiated on leaf and bud (terminal and axillary buds) explants using Murashige and Skoog (MS) medium. Callus response induction percentage, fresh weight, color and texture of the callus were assessed after 1.5 and 6.0 months in culture. The appropriate medium for callus initiation on leaf explants was MS medium supplemented with 6.0 mg/L NAA. A combination of 0.2 mg/L BA and 1.5 mg/L NAA also exhibited a remarkable callus induction on bud explants. Effect of thidiazuron (TDZ) addition to the cultu
... Show MorePots experiment was conducted in the green house of Biology Department, College of Education ( Ibn-AL-Haithum), University of Baghdad , during the growing season of 2005-2006 , to study the effect of five levels of urea fertilizer (0,50,100,150and 200) mg/pot in on vegetative growth of one wheat cultivar (Adanania) upon randomized complete block design with four replications. The results showed that significant difference between urea fertilizer levels above in vegetative growth characteristics ( plant height , leaf area , chlorophyll content, dry matter weight , relative efficiency and relative yield ) It was also showed that 200 mg/pot level was superior to urea fertilizer levels others in above charac
... Show MoreDespite extensive investigations, an effective treatment for sepsis remains elusive and a better understanding of the inflammatory response to infection is required to identify potential new targets for therapy. In this study we have used RNAi technology to show, for the first time, that the inducible lysophosphatidylcholine acyltransferase 2 (LPCAT2) plays a key role in macrophage inflammatory gene expression in response to stimulation with bacterial ligands. Using siRNA- or shRNA-mediated knockdown, we demonstrate that, in contrast to the constitutive LPCAT1, LPCAT2 is required for macrophage cytokine gene expression and release in response to TLR4 and TLR2 ligand stimulation but not for TLR-independent stimuli. In addition, cells transfe
... Show MoreSoaking dentures with disinfection solutions is an effective way of keeping dentures in a healthy status; however, immersions in these solutions have a negative effect on the bond strength of denture base and denture teeth. The aim of this study was to evaluate the bond strength between denture acrylic teeth and heat-cured Poly (methyl methacrylate) denture base material (with and without nano silica) after disinfection with different chemical disinfectants for a simulated period of six months. One hundred specimens of maxillary central incisors attached to PMMA were divided into two groups; 50 specimens of PMMA without nano silica and 50 specimens of PMMA reinforced with 5 wt% of nano silica. Specimens of each group were immersed in five i
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