The performance and durability of the asphalt pavement structure mainly depend on the strength of the bonding between the layers. Such a bond is achieved through the use of an adhesive material (tack coat) to bond the asphalt layers. The main objective of this study is to evaluate the effect of moisture in conjunction with repeated traffic loads on the strength of the bonding between asphalt layers using two types of tack coats with different application rates. Using the nominal maximum size of aggregate (NMAS), the layers were graded (25/19) and (19/9.5) mm. The slabs of multilayer asphalt concrete were prepared using a roller compactor using two types of tack coats to bond between layers, namely rapid curing cut back asphalt (RC-70) and cationic medium setting emulsion (CMS), with different application rates. Six extruded cores with a diameter of 116 mm each form the prepared slab has been obtained. Core specimens were subjected to moisture damage according to the American Association of State Highway and Transportation Officials (AASHTO), after which repeated bond shear stresses and monotonic tests are practiced. It is concluded that permanent deformation increased with moisture-induction under repeated load for both interfaces and tack coat types. The (CMS) as a tack coat had less permanent deformation values than RC-70 for both interface types and all application rates. In contrast, the interface bond strength (IBS) value was higher than that for (RC-70) in both interface types after moisture conditions. The trend of the results illustrates that (IBS) decreased with moisture conditions under repeated load, as compared to samples under repeated load only.
Improving the accuracy of load-deformation behavior, failure mode, and ultimate load capacity for reinforced concrete members subjected to in-plane loadings such as corbels, wall to foundation connections and panels need shear strength behavior to be included. Shear design in reinforced concrete structures depends on crack width, crack slippage and roughness of the surface of cracks.
This paper illustrates results of an experimental investigation conducted to investigate the direct shear strength of fiber normal strength concrete (NSC) and reactive powder concrete (RPC). The tests were performed along a pre-selected shear plane in concrete members named push-off specimens. The effectiveness of concrete compressiv
... Show MoreThis paper describes flexural behavior of two spans continuous rectangular concrete beams reinforced with mild steel and partially prestressing strands, to evaluate using different prestressing level and prestressing area in continuous prestressed beams at serviceability and ultimate stages. Six continuous concrete beams with 4550 mm length reinforced with mild steel reinforcement and partially prestressed with two prestressing levels of (0.7fpy or 0.55fpy.) of and different amount of 12.7 mm diameter seven wire steel strand were used. Test results showed that the partially prestressed reinforced beams with higher prestressing level exhibited the narrowest crack width, smallest deflection and strain in both steel and concrete at ul
... Show MoreThis paper presents a research for magnetohydrodynamic (MHD) flow of an incompressible generalized Burgers’ fluid including by an accelerating plate and flowing under the action of pressure gradient. Where the no – slip assumption between the wall and the fluid is no longer valid. The fractional calculus approach is introduced to establish the constitutive relationship of the generalized Burgers’ fluid. By using the discrete Laplace transform of the sequential fractional derivatives, a closed form solutions for the velocity and shear stress are obtained in terms of Fox H- function for the following two problems: (i) flow due to a constant pressure gradient, and (ii) flow due to due to a sinusoidal pressure gradient. The solutions for
... Show MoreOne of the most common procedures in oral surgery is the removal of impacted mandibular third molars, often followed by pain, swelling, alveolitis, and trismus. Purpose. To compare the outcomes of the intrasocket application of 1% hyaluronic acid oral gel (HA) and advanced platelet-rich fibrin (A-PRF) on the expected postoperative complications, pain, swelling, and trismus follow the surgical extraction of the impacted mandibular third molar. Material and Methods. A randomized controlled trial was conducted at the Oral and Maxillofacial Surgery Unit, Dental Teaching Hospital. Healthy patients who required surgical removal of the impacted mandibular third molar were divided randomly into three groups. The extraction site of the group
... Show MoreThe research aim to the usage educational method for jump shooting and it effect on speed strength in basketball for the specialist students in College Sport of Dayla University, which used the following statistic treatment (The T.test for compatible specimens), so after statistic treatment which appears theres a tow moral differences in speed strength and jump shooting tests results to (legs & arms) for the before and after tests, and after that the conclusions we positive and the second the special drills effect immaterial speed strength to legs and arms, so the tow researches recommended to looking after the best for educational methods that used in our sport colleges in Iraq.
The research aims to conduct a comparative study between the events (800) m and (1500) m track in the types of muscular strength and to identify the differences between them among Iraqi sports club players. The sample represented the players participating in the Iraqi Athletics Championship for the period between (02/11/2023) and (04 /11/2023), and their number was (16) players (8) for each event, as the selection was made intentionally. The researchers used the descriptive approach to achieve the goal of the research and used the statistical package (SPSS) to process the data statistically. According to the results collected, it was found that there was superiority among the intermediate track players (800) m in explosive power and the s
... Show MoreCinnamon plant is considered one of important medicinal plants because it is rich with many active compounds. This research is aimed to study possible effects of extract in culture media of Gardenia jasmenoides. Alcoholic extract was prepared from the bark of cinnamon at different concentrations (0.0, 1.0, 2.0) mg/L, then added to culture media to notice the effect of these concentrations on the growth and development of tissues and organs of Gardenia jasmenoides Ellis in vitro. Results showed the positive effect of increasing callus fresh weight and shoot proliferation from single nodes with presence of plant regulators, 5.0 mg/L Naphthalene acetic acid (NAA) and 3.0 mg/L Benzyl adenine (BA). Results showed that extract has a slight eff
... Show MoreThe oncolytic viruses are promising form of cancer therapy which is based on the selectively killing of the cancer cells. This study was aimed to investigate the role of Newcastle disease virus (NDV) Iraqi strain AD2141 in apoptosis. Firstly, the virulence of AD2141 was detected in embryonated chicken eggs after 48hrs of infection. It was observed a hemorrhage in the skin of infected embryos that led to death. Then, the ability of this strain for regression cancer cell lines was examined. By using cytotoxicity test, it was found 128 HAU/ml of AD2141 had a potent inhibition against growth of RD and AMN3 after 72hrs of exposure time; the inhibition rate was 86.8% and 86.98% respectively. Moreover, the apoptotic activity of AD2141 was exami
... Show MoreHighly plastic soils exhibit unfavorited properties upon saturation, which produce different defects in engineering structures. Attempts were made by researchers to proffer solutions to these defects by experimenting in practical ways. This included various materials that could possibly improve the soil engineering properties and reduce environmental hazards. This paper investigates the strength behavior of highly plastic clay stabilized with brick dust. The brick dust contents were 10%, 20%, and 30% by dry weight of soil. A series of linear shrinkage and unconfined compression tests were carried out to study the effect of brick dust on the quantitative amount of shrinkage experienced by highly plastic clay and the undra
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