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).
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This research was interested in studying the phrase “I don’t know” in the Lisan al-Arab dictionary, and Lisan al-Arab was based on collecting its material from five dictionaries, including: Tahdhib al-Lugha, al-Muqamah, al-Sahih, and the footnotes of Ibn Berri, al-Nihaya and Gharib al-Hadith. The objection to this phrase, and the discussion of its various implications among linguists and the clarification of the closest and most famous content to it according to the data presented to the researcher in his research journey, and to reach this goal, the research division into a preface, five demands and a conclusion and followed the list of sources and references. To define the lexicon of Lisan al-Ar
... Show MoreThroughput accounting is concerned with a throughput measurement process to determine the efficiency of the company, to know the problems and obstacles it suffers from, to determine their causes and ways to address them.The research problem is represented by the following question: does the application of a throughput accounting lead to maximizing the company's profits? The aim of the research is to demonstrate the importance of throughput accounting, which is one of the tools of management accounting in providing an efficient information system that provides the company’s management with the information it needs to improve its production processes, increase a throughput, and thus maxi
... Show MoreThis research is a comparative jurisprudential study that focuses on Imam Al-Bayhaqi’s preferred opinions in his book Al-Khilafiyat (The Disagreements), the part of Al-Rida’a (Breastfeeding). It is considered one of the most important familial topics that is concerned with organizing the social relations in Islam, strengthens the family ties and that prevents the family disintegration due to the ignorance and lack in comprehending Sharia laws (Islam law) in all aspects. The study follows the inductive and descriptive method. It aims at examining the prohibition of marriage when breastfeeding takes place at the time of woman’s conversion to Islam or during her infidelity period. It further aims at verifying the prohibition
... Show Moreتم استخدام خرائط ضبط الجودة الإحصائية لتقييم جودة الخدمة التعليمية في جامعة الباحة، ويهدف هذا البحث إلى استخدام خرائط ضبط الجودة الإحصائية لقياس مستوى الجودة وفجوة الجودة بين توقعات الطلبة وإدراكاتهم لمستوى الخدمة الذي تقدمه جامعة الباحة. حيث تم اختيار عينة من 200 طالب وطالبة عشوائيا باستخدام العشوائية العنقودية من 4 كليات خلال الفترة 01 – 30/2015م، وجمعت البيانات من خلال استبيان جودة الخدمة الذي يقيس ت
... Show MoreObjective: The study aimed to screen the prepubertal children for idiopathic scoliosis at earlier stages, and find
out the relationship between idiopathic scoliosis and demographic data such as age, sex, body mass index,
heavy backpacks, and heart & lung diseases.
Methodology: A descriptive study was conducted on screening program for prepubertal children in primary
schools at Baghdad city, starting from 24th of February to the end of October 2010. Non- probability
(purposive) sample of 510 prepubertal children were chosen from primary schools of both sides of Al-Karkh
and Al-Russafa sectors. Data was collected through a specially constructed questionnaire format include (24)
items multiple choice questions, and
The purpose of this paper is to find the best multiplier approximation of unbounded functions in –space by using some discrete linear positive operators. Also we will estimate the degree of the best multiplier approximation in term of modulus of continuity and the averaged modulus.