Highly Modified Asphalt (HiMA) binders have garnered significant attention due to their superior resistance to rutting, fatigue cracking, and thermal distress under heavy traffic loads and extreme environmental conditions. While elastomeric polymers such as Styrene- Butadiene-Styrene (SBS) have been extensively used in HiMA applications, the potential of plastomeric polymers, including Polyethylene (PE) and Ethylene Vinyl Acetate (EVA), remains largely unexplored. This study aims to evaluate the performance of reference binder (RB) modified with plastomeric HiMA asphalt in comparison to SBS-modified binders and determine the optimal polymer dosage for achieving an optimal balance between rutting resistance and fatigue durability. The experimental program involved modifying a base asphalt binder with SBS, PE, and EVA at dosages of 6%, 7%, and 8% by weight of binder. A comprehensive evaluation was conducted, including conventional tests (penetration, softening point, viscosity, mass loss, storage stability, and specific gravity) and rheological characterization using the Dynamic Shear Rheometer (DSR). The Multiple Stress Creep Recovery (MSCR) test was employed to assess high-temperature performance, while the Linear Amplitude Sweep (LAS) test evaluated fatigue behavior. Additionally, an Overall Desirability (OD) analysis was performed to integrate multiple performance criteria and establish a ranking for each modification. The results demonstrated that SBS-modified binders exhibited the most balanced performance, with SBS8 achieving the highest elastic recovery (52.87%) and superior fatigue life, exceeding 1,017,904 cycles at 2.5% strain. PE8 exhibited exceptional rutting resistance, reaching the lowest Jnr 3.2 value (0.0078 kPa−1); however, its limited elasticity (15.7% recovery) indicated reduced flexibility. EVA modifications demonstrated marginal improvements in fatigue resistance but failed to meet the AASHTO M332 criteria for high-traffic applications. The OD analysis ranked SBS8 as the most effective HiMA binder (OD score = 0.715), followed by SBS7 (0.588) and SBS6 (0.509). PE7 (0.354) and PE6 (0.337) demonstrated moderate performance, whereas EVA had the lowest desirability score (0.000). Based on these findings, SBS-modified binders are recommended for applications requiring a balance between fatigue and rutting resistance, whereas PE-based HiMA is more suitable for high-temperature regions where rutting is the primary concern. Further field studies are necessary to validate the long-term durability of plastomeric HiMA binders and optimize their use for specific pavement conditions.
The research aims at identifying the organizational performance of the kindergarten teachers and defines the educational environment of kindergarten children. To achieve the objectives of the research, the researcher adopted the organizational performance scale for (Saadi, 2016), which was applied to kindergarten teachers. The scale consists of (43) paragraphs, and has good reliability and validity, as the coefficient of reliability (84.0) in a retest method, and (87.0) using the formula Alpha Kronbach. Additionally, the researcher adopted the educational environment scale for (Radam, 2015); the scale consists of (66) paragraphs, and it enjoys a good reliability and validity, as the coefficient of reliability (89.0) method of reliability
... Show MoreThe competitive environment influences the increase in exercise intensity and hence adds to the growth of training and practice. The study objective.to identify the effect of competitive speed exercises on the effectiveness of skill performance and speed of counterattack for junior boxers, as well as to know the rate of development for these variables.Materials and methods. The research sample consisted of twelve up-and-coming Al-Najda Sports Club players who participated in the national tournament and were selected with care. They were placed into two groups, control and experimental, with six boxers each in the control and experimental groups. The two groups were assigned identical weights on purpose, and their ages range from 15 to 16 ye
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The hotel sector is one of the most vital sectors exposed to risks, and the authorities concerned with control must take their active and influential role in putting the hotel sector on the right track and compatible with the internationally approved approaches, and the importance of auditing the performance of the hotel sector in light of the (Covid-19) pandemic is embodied in the fact that it gives a clear and realistic picture to the management and regulatory bodies about the performance and activities of this sector and the shortcomings and deviations that must be addressed, and also helps government decision makers to ob
... Show MoreThe research aims to determine the impact of Human Resources Accounting (HRA) on employee’s performance. The research’s problem was embodied in the lack of interest in HRA, which was reflected on the performance of employees in the Ministry of Education; the research adopted the descriptive-analytical approach, and the research community included the directors of departments and people at the headquarters of the Ministry of Education. The sample size was (224) individuals from the total community of 533. The questionnaire was adopted as the main tool for collecting data and information, as well as the interviews that were conducted by the researcher. In order to analyze t
... Show MoreIn solar-thermal adsorption/desorption processes, it is not always possible to preserve equal operating times for the adsorption/desorption modes due to the fluctuating supply nature of the source which largely affects the system’s operating conditions. This paper seeks to examine the impact of adopting unequal adsorption/desorption times on the entire cooling performance of solar adsorption systems. A cooling system with silica gel–water as adsorbent-adsorbate pair has been built and tested under the climatic condition of Iraq. A mathematical model has been established to predict the system performance, and the results are successfully validated via the experimental findings. The results show that, the system can be operational
... Show MoreCentral banks around the world typically use various financial indicators to evaluate performance. In Iraq, the indicators used by central banks to evaluate the performance of banks are of great importance to ensure that the banks operating within the Iraqi banking system comply with the regulatory and legal requirements issued by the Central Bank of Iraq or the Ministry of Finance. Given the need to study the profitability indicator to ensure its ability to evaluate the performance of specialized banks in Iraq, these banks carry out their banking activities and businesses through capital funded by the government. The use of profitability indicators in evaluating the performance of specialized banks provides information about the profitabil
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