This study investigates the characterization and mechanical performance of Stone Mastic Asphalt (SMA) mixtures modified with two types of polymers: styrene–butadiene–styrene (SBS) and high-molecular-weight polyethylene (PE). Neat asphalt cement PG 64-16 was modified using a higher content of SBS and PE at concentrations of 6%, 7%, and 8% by weight of asphalt through the dry blending method to produce Highly Modified Asphalts (HiMA). The physical and rheological properties of the modified binders were evaluated using penetration, softening point, rotational viscosity, and dynamic shear rheometer (DSR) tests. Also, their phase compatibility and morphological changes were evaluated using the storage stability testing and scanning electron microscopy (SEM) analysis. The mechanical performance of the corresponding SMA mixtures was assessed through Marshall stability and flow, moisture susceptibility, crack tolerance index (CT-index), resilient modulus, and rutting resistance tests. Also, a mechanistic durability analysis was conducted using the KENLAYER software. Results indicated that both polymers enhanced the binder’s stiffness and high-temperature performance, with SBS exhibiting greater overall improvements. SBS-modified binders displayed a relatively low softening point difference (ΔT) of 5.1 °C to 5.8 °C, indicating good thermal stability and uniform polymer dispersion. In contrast, PE-modified binders exhibited significantly higher ΔT values, reaching 13.5 °C with 8% PE content, indicating a greater tendency toward phase separation. Moreover, Marshall stability improved substantially, increasing by 43% for 8% SBS-modified mixes and 28% for 8% PE-modified mixes compared to the neat SMA mix. Flow number (FN) results indicated enhanced rutting resistance, with FN values increasing by 2.45 times for SBS mixes and 2.1 times for PE mixes at 8% polymer content. Additionally, moisture susceptibility was significantly improved, as evidenced by the tensile strength ratio (TSR) values of 97% with 8% SBS and 92% with 8% PE, compared to 81% for the neat mix. Resilient modules increased notably, with a 38% rise for 8% SBS mixes and a 24% rise for 8% PE mixes, reflecting enhanced stiffness and load-bearing capacity. Also, the CT-index significantly improved, reaching values of 154 for the 8% SBS mix and 127 for the 8% PE-modified mix, compared to 86 for the neat mix, indicating enhanced resistance to cracking. Finally, both polymer-modified mixes demonstrated improved durability, where the 8% SBS mix exhibited the longest design life (21.66 years) and the highest number of allowable load repetitions (5.42 × 106), followed by 8% PE (13.98 years and 3.50 × 106 repetitions).
Abstract
The Purpose of This Research is The Main Factors In out Comes Phenomena From Primary School Which in Creased in Lost Period in Iraq And to Find Solutions to The This Problem.
In Order to Achieve Al The Aim The Research Choose a Systematic Random Sample of School Records For Students in Some Primary Schools in Karkh and Rusafa and Year of Study (2010-2015) and Size (40) Samples, included (16) Variable , Collected in Form Prepared by The Research As a Way to Analyze The Data.
Remember to Summarize The (6) Main components Pay a Student to Drop out of Primary Schools in The Province of Baghdad are Arranged As Follows:
... Show MoreAcute lymphoblastic leukemia (ALL) is a cancer of the blood and bone marrow (spongy tissue in the center of bone). In ALL, too many bone marrow stem cells develop into a type of white blood cell called lymphocytes. These abnormal lymphocytes are not able to fight infection very well. The aim of this study was to investigate possible links between E3 SUMO-Protein Ligase NSE2 [NSMCE2] and increase DNA damage in the childhood patients with Acute lymphoblastic leukemia (ALL). Laboratory investigations including hemoglobin(Hb) ,white blood cell (WBC) , serum total protein , albumin ,globulin , in addition to serum total antioxidant activity (TAA) , Advanced oxidation protein products(AOPP) and E3 SUMO-Protein Ligase NSE2[NSMCE2]. Blood samples
... Show MoreObjective: Determination the effectiveness of educational program on female students’ practices toward premenstrual.
Methodology: A quasi-experimental design study was conducted involving (140) student purposely in four secondary schools at Al-sadder city (70) student for study group and (70) for control group. The prevalence of PMS selected through American College of Obstetricians and Gynecologists (ACOG) (2015) criteria to select PMS students before program. The education program were set in four steps, the first step (pre-test) is to assess the practices, before the implementation of the program, the second step is implementing the program, following two steps post-test I and II betwe
... Show MoreThe research aims to identify the effect of teaching according to the augmented reality on the technique of the visual thinking skills among scientific fifth-grade students in a biology course. In order to achieve the goal of the research, the researcher adopted the experimental approach with the partial set of the two equal groups with the dimensional test of visual thinking skills, The research population represented all the scientific students of the fifth grade for morning government schools affiliated to the General Directorate of Education of Baghdad / Karkh II, alshakerin preparatory for boys was chosen intentionally, in which two groups were chosen for this study, one group is chosen randomly as the control group via lottery, whe
... Show MoreA large number of natural or synthetic dyes have been removed from both national and international lists of permitted food colors because of their mutagenic or carcinogenic activity. Therefore, this study aimed to use the Random Amplified Polymorphic DNA-Based Polymerase Chain Reaction (RAPD-PCR) assay as a feasible method to evaluate the ability of some food colors as genotoxin-induced DNA damage and mutations. Lactiplantibacillus plantarum was used as a bioindicator to determine the genotoxic effects by RAPD-PCR using M13 primer after treatment with some synthetic dyes currently used as food color additives, including Sunset Yellow, Carmoisine, and Tartrazine. Besides qualitative analysis, the bioinformatic GelJ software was used for clus
... Show MoreThe study aimed to know the degree to which Islamic education teachers employ the strategy of directed discovery in teaching to develop higher thinking skills (analysis, synthesis, and evaluation) among sixth-grade students at the basic stage in East Nile Province, Khartoum State - Sudan. The researcher used the descriptive-analytical method, and adopted a questionnaire that consisted of (15) indicators representing the skills of analysis, synthesis, and evaluation as a tool of the study. A random sample of (175) Islamic education teachers was selected, from the Department of Basic Education. The data were analyzed according to the Statistical Packages for Social Sciences (SPSS) program, and the results of the study have shown that the u
... Show MoreThis study analyses six political cartoons selected based on their relevance to current Iraqi political issues, specifically the period between 2005 and 2015, from American online newspapers (calgecartooms.com). The selection criteria included the cartoons' satirical elements, visual rhetoric, and their ability to engage with themes such as power dynamics, social issues, and public opinion. It sheds light on how these cartoons can function as mediators of meanings between the cartoonists and the readers. The data is examined using multimodal discourse analysis (MDA), which combines language study with the analysis of other visual elements, like colors, gestures, and images, to understand meaning (O’Halloran et al., 2011). The Visual Socia
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