A ‘locking-bolt’ demountable shear connector (LBDSC) is proposed to facilitate the deconstruction and reuse of steel-concrete composite structures, in line with achieving a more sustainable construction design paradigm. The LBDSC is comprised of a grout-filled steel tube and a geometrically compatible partially threaded bolt. The latter has a geometry that ‘locks’ the bolt in compatible holes predrilled on the steel flange and eliminates initial slip and construction tolerance issues. The structural behaviour of the LBDSC is evaluated through nine pushout tests using a horizontal test setup. The effects of the tube thickness, strength of concrete slab, and strength of infilled grout on the shear resistance, initial stiffness, and ductility of the LBDSC are assessed. The experimental results show that the LBDSC can achieve higher shear resistance and similar initial stiffness as compared to traditional welded studs. In addition, all tested LBDSCs exhibited slip capacities ranging from 14 to 32 mm and can be classified as ductile shear connectors according to Eurocode 4. A detailed finite element model was also created and found to be reliable to reproduce the experimental behaviour. Parametric studies were subsequently conducted using the validated model to study further parameters and generalise the experimental results. Due to the specific test setup, non-negligible uplift forces were generated in the connector and the potential implications are discussed.
The main goal of the current research is to know -Environmental problems included in the content of the two science books (chemistry units) for intermediate stage
A list of environmental problems had been prepared and consisting of (8) main areas which are (air and atmosphere pollution, water pollution, soil pollution, energy, disturbance of biodiversity and environmental balance, waste management, food and medicinal pollution, investment of mineral wealth). Of which (60) sub-problems, at that time the researcher analyzed the two science books (two chemistry units) for the intermediate stage of the academic year (2020-2021) in light of the list that was prepared, and the validity and consisten
... Show MoreThe objective of this research is to analyze the relationship between the Factors of critical success and sustainable competitive advantage, and I have tested Search Company Mu'tasim General Contracting, through applied on a sample of (90) manager, engineer and project manager, spread over sections and the company's projects surveyed. has been selected sector construction industry as one of the sectors vital and important that play a major role in the advancement of Iraq's infrastructure under the current circumstances, which epresent a set of Projects are Mu'tasim General Contracting construction imple
... Show MoreRegional immune response with mammary gland carcinoma was
studied statistically. However, the prognostic value remains
conflicting. Thirty mice were used in this study which infected
were with mammary gland carcinoma. The tumor size of the animals
under study were measured before and after laser irradiation by using
a vernier and compared these results were with that of non irradiated
animals with laser (control group)
The aim of this study was to evaluate the effect of low level laser
therapy (LLLT) on increasing the response of immune system by
stimulating the lymph node action to decrease the cancer cell activity
and then decreasing the tumor size of an infected mice.
The results of the gross observati
From the responses of Imam Abi Zakaria al-Nawawi 676 AH on the grammarians in his commentary on Sahel Muslim
Klebsiella pneumoniae capsular polysaccharide (CPS) antigen was evaluated for their capability to increase immune responses. And, CPS neutralizing antibodies were approved as the main response to vaccination in many disease. Therefore, killed Stapthylococcus aureus bacteria was employed to evaluate K. pneumoniae CPS adjuvanticity. The mice groups were immunized (orally, intra-peritoneally and by swab skin)with a dose of (25μl of formalin killed S. aureus (1.5 x 108) with a CPS at dose 175μl/kg at a conc.50 μg/ml) vaccination occurred in first day then recurrent vaccination as booster dose beyond seven days. After first 7 days, the results revealed elevation of IL2,4,10,12 and IgG levels occurred mainly in oral and swab skin groups, an
... Show MoreThe spectral propetties (absorption and fluorescence) of Coumarine-47 laser dye have been studied. This type of laser dye belong the Coumarine family and it has dissolved in chloroform at different concentrations (1x10-5, 5x10-5, and 1x10-4 M) at room temperature. The achieved results have been pointed out to increase in the absorption and fluorescence as the concentration increased which are agreements with Beer – Lambert law. These have been also showed an expansion in the spectral range of absorption and fluorescence with a noticed shift in the direction of longer wavelength (Red-shift) with increasing concentration. The quantum efficiency of the dissolved C47 in chloroform has been computed by using the brevious concentrations
... Show MoreIn this research, we have measured specific activity concentrations in five samples for raw materials used in ceramic industry in AL-Ramadi ceramic factory by using (HPGe) detector. The results have shown that, the average specific activity, for 238U, 232Th and 40K are equal to (18.300±6.4 Bq/kg), (17.988±6.1 Bq/kg), (167.952±63.5 Bq/kg), respectively. In order to assess the radiological hazards of the radioactivity in samples, radium equivalent activity, absorbed gamma dose rate, indoor and outdoor annual effective dose rates, gamma Index and both (external and internal) hazard effects have been calculated. All results were found to be less than the allowed global limit given by (UNSCEAR, 2000).
... Show MoreMangrove landscaping in the Segara Anakan Lagoon (SAL) is an adaptation pattern of mangrove ecosystems to live and grow in unstable areas. This research aimed to develop a mangrove landscape to mitigate the impacts of ocean waves, currents, and inundation due to climate change. The study was conducted in SAL and Cilacap Coast (CC) using the environmental properties and climate change data. The data obtained were analyzed using mapping and trendline analyses. The results showed that mangrove landscaping in Segara Anakan had four zones with Nypa frutican, Rhizophora styllosa, Aegiceras corniculatum, Rhizophora apiculata, Avicennia marina, Sonneratia alba identified as the best adaptation of mangrove species. Climate change give a high impa
... Show Moreالمواقف افي الدول العربية قراءة تحليلية في مواقف لدولية من التغيير (الولايات المتحدة - الاتحاد الاوروبي - روسيا)
The predatory bush crickets Saga ephippigera Fischer Von Waldheim, 1846 is the largest Iraqi orthopterans and one of the most active and successful predators in the Kurdistan region. The nymphs and adults prey on all the stages of various species of insects. Twelve adult specimens were collected from Erbil Province during May 2018 and June 2021. Morphological structures of the adult insects were described and illustrated in details; important taxonomic characteristics of body regions with their appendages were chosen; and the results indicated the importance of morphological characteristics which confirmed the identification of this species correctly.