Enhancing Asphalt Mixture Properties through Waste Plastic and Steel Fiber Additives: A Comprehensive Study

Asphalt concrete is extensively used in road construction due to its superior mechanical properties and long-term durability. This study investigates the effect of steel fiber reinforcement on the performance characteristics of Stone Matrix Asphalt (SMA) and Asphalt Concrete (AC) mixtures. The Marshall mix design method was employed to develop SMA mixtures, and the Marshall Stability Test was conducted to determine the optimal steel fiber dosage. Steel fibers were incorporated to improve resistance to rutting and cracking, with the optimal dosage identified as 0.3% of the total mix weight. Furthermore, this study examines the behavior of steel fibers in SMA applications and optimizes the plastic content in AC mixtures. The results indicate that incorporating 2.5% waste plastic enhances AC's workability and handling characteristics compared to conventional mixtures. Additionally, a 3% waste plastic content demonstrated improved drain-down resistance and tensile strength properties, highlighting its potential for performance enhancement in asphalt pavements

Towards Greener Skies: Natural Fibres for Aeronautical Applications

Choosing materials mostly involves taking their sustainability into account. The material selection for airplane internal product design is heavily influenced by the enormous demand, knowledge of the ecological effect, and appropriateness among a material’s performance, properties, and adequacy for the part to be utilized. In this study, natural fibres for aeronautical applications were chosen using a step-by-step methodology. To have a better understanding, data about the mechanical, physical, and chemical features of bio-fibres were gathered and subjected to a hierarchical analysis prior to the start of the selection process. For this purpose, three physical subcriteria (crystallinity index, density, and moisture content), three mechanical subcriteria (young’s modulus, tensile strength, and “elongation at break”), and three different chemical subcriteria (lignin, hemi-cellulose, and cellulose) were taken into consideration. Subsequently, hierarchy strategies were applied to identify the weights assigned to the attributes based on the notional significance of each attribute

Influence of Aggregate Type and Size on Residual Mechanical Properties of Post-Heated Geopolymer Concrete: Experimental Study and Applications of Artificial Neural Networks

To mitigate environmental impacts from Portland cement (PC) production, the researcher’s efforts is introducing eco-friendly alternatives such as Geopolymer concrete (GPC). While GPC shows promise, further research is required to understand how fire or elevated temperatures affect GPC’s mechanical properties. This research investigates the effects of elevated temperatures (200℃, 400℃, 600℃, and 800℃) on the residual mechanical properties (compressive, flexural, splitting-tensile strengths, and modulus of elasticity) of ambient-cured fly-ash (FA)-based GPC compared to PC mixtures. The study examined various concrete types (GPC and PC), three coarse aggregate types (basalt, gravel, and crushed dolomite), and three crushed dolomite sizes (40 mm, 20 mm, and 14 mm). Additionally, Artificial Neural Network (ANN) models were developed to predict the residual compressive strength of both ambient-cured and heat-cured GPC after exposure to elevated temperatures. Results showed that basalt aggregate significantly enhanced the residual mechanical properties at 800 ℃, outperforming crushed dolomite and gravel in compressive, flexural, splitting-tensile strengths, and modulus of elasticity, with increases of (20%, 80%), (26%, 244%), (10%, 100%), and (14%, 140%), respectively. Moreover, the residual mechanical properties were found to be inversely proportion with max size of coarse aggregate. In addition, using ANN models proved its efficient in predicting the compressive strength for both ambient and heat-cured GPC with R² values of 0.94 and 0.887, respectively

حوارية النص الديني في الرواية العربية رواية "ألواح ودسر" لأحمد خيري العمري أنموذجا

This study seeks to demonstrate the openness of the textual text to the religious text, and the ability of the text to interrogate its stories, as the Arabic novel has benefited from the religious text and licensed its discourse by projecting it onto reality, since the stories in the Holy Quran are reproduced in every era with new concepts and different social, intellectual and ideological visions. The religious text was and still is an inspiration in the literary art, especially the novel, which has occupied a wide space among the literary genres today. Novelists have been saturated with the stories of the religious text, and the latter has increased the strength of the literary discourse and its impact, and the meeting of two texts interacted in the form of dialogue that is under study, taking tablets and dwarfs as novels to work

Effect of geopolymerization on geotechnical characteristics of palm kernel shell ash stabilized laterite

Laterite soils (LS) in tropical and subtropical regions exhibit poor engineering properties, making them unsuitable for road construction application. This study examined impact of alkaline activation on palm kernel shell ash (PKSA) stabilized LS. LS properties such as Liquid Limit (LL), Plastic Limit (PL), Optimal Moisture Content, Maximum Dry Density, and California Bearing Ratio (CBR) were determined to ascertain whether it is suitable as a roadway building material. The LS was mixed with different proportions (3, 6, and 9%) of PKSA only and then with an alkaline activator (i.e. 10 M Na2SiO3/NaOH). The earlier mentioned properties of the stabilized LS were determined. An X-ray diffraction test was conducted to examine the mineral composition of PKSA. The results show that the LS, in its natural state, is unsuitable for road construction applications without proper stabilization. Increasing the percentage of PKSA decreased LL, OMC and MDD for PKSA-based and PKSA-geopolymer-based stabilized LS. Furthermore, the CBR of PKSA stabilized soil improved by 77%. Upon further addition of alkaline activator, the CBR value increased by 50% when compared with the natural soil. It was concluded that adding an alkaline activator significantly impacts soil properties for construction. This environmentally friendly method can contribute to sustainable soil stabilization practices in tropical and subtropical regions

Stochastic Stability Analysis of Columns with Randomly Elastic Joint Ends and Two-Dimensional Random Material Properties Using Monte Carlo Simulation

This paper develops a Monte Carlo simulation (MCs) to analyze the stochastic stability of a pin-ended column with elastic rotational springs at both ends. The randomness of input factors is considered, including the rotational stiffness of elastic couplings at both ends of the column as random variables following a normal distribution and the elastic modulus of the column as a two-dimensional (2D), stationary, homogeneous Gaussian random field. The spectral representation method is applied to represent the 2D random field and generate realizations of the elastic modulus. The influence of random factors such as the standard deviation of the 2D random field, the standard deviation of normal random variables, and correlation distance in each direction on the coefficient of variation (COV) of the critical load is analyzed in detail in this study. The results indicate a strong correlation between the COV of the critical load and both the standard deviation of the 2D random field and the correlation distance. The COV increases significantly with increasing standard deviation, particularly for larger correlation lengths. However, the influence of the variability of rotational stiffness is relatively minor, especially at larger correlation distances

حجاجية البديع في كتاب: (جمهرة خطب العرب في عصور العربية الزاهرة) لأحمد زكي صفوت

Al-Badi' (figurative style) was studied in successive times as a verbal adornment whose purpose was to improve and entertain، but it was an incomplete lesson that was clearly mistaken. as it cannot be said about the manifestations of al-Badi' in the Qur'an and authentic poetry that they are Appearances of beauty and entertaining only، but the modern argumentative theory has returned the methods of al-Badi' to the ranks of important speech strategies، in terms of approaching them based on the fact that the process of deviation and choice is always loaded with an intended persuasive meaning. If the traditional Arabic sermon is an oral sermon with a limited persuasive status that requires condensation and focus، then the orator's deviation from the normal level of speech and his choice of the al-Badi' style must carry within it an additional meaning that strengthens the thesis and establishes it in the souls of the recipients، which is what this research attempts to clarify and stand on its truth

Enhancement of Mechanical Properties of Unfired Clay Bricks Using Rice Husk Ash and Fibre Reinforcement

This study investigates the production of unfired clay bricks incorporating cement and rice husk ash (RHA) as a binder, with rice husk (RH) serving as fiber reinforcement. The need for eco-friendly building materials is critical, as cement production contributes 7-8% of global CO₂ emissions, and while fired clay bricks are stronger, their high production cost due to significant energy requirements makes them less sustainable. Providing lower-cost building materials can reduce rural-to-urban migration and make housing more affordable for low-income earners. RH fibers were added in varying volumes (0, 5, 10, 15, 20, and 25 vol%) while maintaining a constant RHA and cement content of 10 vol.%. The mixed clay bricks were dried for seven days and cured at room temperature (22°C to 28°C) for 21 days, totalling 28 days of curing. Mechanical properties, including compressive strength, flexural strength, and fracture toughness, were evaluated alongside the chemical composition and textural characteristics of the clay and RHA. Particle size distribution (PSD) analysis classified the clay as sandy clay with higher sand content, determined using sieve analysis and the hydrometer method. X-ray fluorescence (XRF) confirmed that the RHA met NIS/ASTM standards, with a minimum of 70% combined SiO₂, Al₂O₃, and Fe₂O₃, qualifying it as a pozzolanic material. Optimal mechanical performance was observed at 5% RH fiber content, with fibers 2-4 mm in length, achieving compressive strength of 7 MPa, flexural strength of 2.1 MPa, and fracture toughness of 2.15 MPa√m, while fiber content beyond 5% resulted in gradual declines, particularly significant after 20%. The study concludes that RH fiber-reinforced composites are suitable for lightweight, durable building materials, promoting environmental sustainability and improved performance

Reviewing the degradation of environmental pollution in cement concrete structures using Nano-Titanium Dioxide

The rising levels of pollution globally affect cement concrete structures and historical monuments by making them fade, stained, and dull due to settling of dust particles. Titanium Dioxide (NT) is a naturally occurred photocatalytic material when used with construction materials (CM), offers benefits such as environmental pollution degradation and self-cleaning action. Moreover, its application supplements in enacting the original appearance of the structure for longer times. The main aim of this review study is to summarize the current information available primarily on ‘environmental pollution degradation and self-cleaning effect’. The standard tools for effective summarization of existing data like a) PRISMA analysis, b) VOSviewer, and c) Citespace were used. Further, the major research gaps, environmental impacts, concept of sustainability in relation to utilization of NT and future trends are incorporated. This review successfully concludes the potential application of NT in cement concrete structures for possible reduction of environmental pollution