2026-03-10
Nadheer Albayati, Mohammed Qadir Ismael
Asphalt pavement is subjected to considerable recurring stresses that reduce its lifespan and impair its condition, mostly owing to repeated traffic loads and environmental factors, as well as construction quality. As the application of asphalt mixtures in paving roads has increased, asphalt mixture components have attracted interest as they are closely linked to its durability and performance. This paper provides a comprehensive review of the theory of permanent deformation (rutting formation) in asphalt pavements. Types and factors that influence rutting are also discussed. More importantly, laboratory tests are categorized into four fundamental concepts related to the permanent deformation, which aids in selecting the proper test for evaluation, each containing many assessment methods according to American and European practices to analyse the structural behaviour of pavements and changes in their properties over time, which results in significant rutting. Solutions to enhance resistance to rutting are discussed. The paper concludes that rutting is unavoidable when both high temperatures and frequent heavy loads are present. Geosynthetics are an effective approach to reducing permanent structural and non-structural deformation; they have demonstrated effectiveness in field applications, in contrast to methods primarily validated through laboratory testing.
2026-01-08
Nidaa Nuaman Mageed, Riyadh Alsultani, Mohammed Kareem Sameer
This paper investigates on the aesthetic values that were employed during residential, commercial and administrative building by comparing statistical data. Findings show that diversity is always one of the most significant aesthetical values, but its comparative significance depends on the type of building. Diversity has a mean score of 4,15 with an importance rating of 83 % in residential buildings, and then rhythm (4,05), harmony (4,01) and contrast (3,98). Complexity gets a lowest score (3,12), and unity, balance, and proportionality are in a moderate range (3,45-3,65). Diversity is once more the most valued in commercial buildings having a mean score of 4,42 and an importance rating of 88,40 %. Balance is also high (4,10), and the values of unity (3,65), rhythm and contrast (3,80) are medium. Complexity is the least desirable element (3,20), and this is in line with a tendency to adopt simple design. In case of administrative buildings, the most stressed values are proportionality (4,15; 83,00 %), and diversity, as well as ratio (3,44; 68,80 %). Balance (3,88) is also appreciated whereas complexity (3,35), harmony, (3,40), and rhythm (3,38) are viewed as mediocre. These results can help architects to be practical in the integration of aesthetic strategies to the intended purpose of a building.
2026-01-04
Kuraisha Kambali, Youventharan Duraisamy, Rokiah Othman, Mohd Arif Sulaiman
The primary objectives of this study were to quantify how Eugenia Oleina (with H-type root architecture) improves slope stability in tropical residual soils and to assess the factors controlling this bio-anchorage effect. Laboratory tests measured soil shear strength (cohesion c′ and friction angle ϕ′) and root tensile properties, and a numerical slope analysis (finite element method) evaluated Factor of Safety (FOS) with and without vegetation under various rainfall scenarios. Results showed that planting E. Oleina increased shear strength: cohesion rose by 8-13 kPa and friction angle by 5-8° compared to unrooted soil, yielding higher FOS values. Root pull-out tests revealed that thinner E. Oleina roots exhibited higher tensile strength than thicker ones, consistent with a power-law trend. Specifically, mature E. Oleina roots (age > 10 yrs) attained tensile strengths 50 MPa, about 2,5 times higher than comparable M-type roots under dry conditions. However, in fully saturated soils, pull-out strength dropped by 33 %, illustrating moisture sensitivity. Finite element analysis confirmed the experimental findings: vegetation consistently improved slope stability (higher FOS) across rainfall conditions, although heavy rainfall (100 % saturation) reduced the FOS relative to moderate rain. These findings have practical implications: E. Oleina (an H-type species) is most effective on slopes up to 20° and 3,5 m high, especially in regions with intense rainfall, where its extensive horizontal roots can bind the soil surface. Guidelines are provided for implementing E. Oleina in bioengineering. The combined experimental and numerical results demonstrate E. Oleina’s value as a sustainable slope reinforcement strategy in tropical residual soils.
2025-12-21
Trong Kien Nguyen, Ngoc Long Tran
Capacity-based design ensures that the structure collapses according to a desired scenario in the event of a large earthquake to minimise loss of life. This design approach has been widely researched and incorporated into some building codes. However, current methods still have limitations, leading to potential uncontrolled collapses in certain scenarios. Many researchers have worked to address these shortcomings, but existing procedures remain complex and challenging to apply in practice. This paper introduces a new design method that focuses on optimising structures beyond the elastic range. First, the frame is calculated for optimal plasticity according to the earthquake load to determine the plastic moments. These plastic moments are used to redesign the cross-sections of beams and columns. The beam cross-section is designed according to the calculated plastic moments. Meanwhile, the moment value for designing the column cross-section is equal to the calculated plastic moment value multiplied by a factor > 1. The results show that the steel frames designed using the proposed method attain a global collapse mechanism. Additionally, the ductile behaviour of the frames has been controlled. A 3-story, 1-span 2D frame and a 6-story, 3-span 2D frame are analysed using this capacity design approach to demonstrate the effectiveness and performance of the proposed procedure and compared with other methods.
2025-10-23
Pramod Kumar, Sanjay Sharma, Bheem Pratap
Sustainable concrete is created using waste materials and contributes to environmental conservation. In this study, fly ash and slag were key ingredients for this sustainable concrete. The focus was on constructing a predictive model using various input variables. To achieve this, machine learning techniques were employed: random forest (RF), support vector machine (SVM), and long short-term memory (LSTM). These algorithms were used to predict the properties of structural concrete produced from fly ash and slag. The predictive model was precisely trained and tested using experimental data. The assessment of model performance involved a comparative analysis based on two metrics: the coefficient of determination score and root mean square error. The coefficient of determination values for the RF, SVM, and LSTM were 0,8439; 0,8668; and 0,8694; respectively. The root mean square error values were 4,0318; 3,9692; and 3,6921 for RF, SVM, and LSTM, respectively. The results of this study demonstrate that the LSTM model outperformed both the RF and SVM models. This suggests that the LSTM algorithm is particularly suitable for capturing complex patterns and relationships within the data, making it well-suited for predicting the properties of sustainable concrete based on fly ash and slag.
2025-09-29
Namratha Sasikumar, Ilamainathan Natarajan, Joanna Philip Saratha
The substructure of a berthing structure with a deep draft presents significant financial challenges. This research offers valuable perspectives on minimizing substructure expenses for a berthing structure by leveraging the Indian Standard (IS) code for deep draft berthing structures in the early project phase for the prompt creation of the bill of quantities. The focus is on achieving efficient results, while adhering to the IS approach, thus avoiding time-consuming analyses. Different analyses of soil-structure interaction, including those based on the Indian Standard (IS) code, Fixity method, linear analysis, and non-linear analysis approaches were conducted utilising actual field soil parameters. Three distinct sites, predominantly comprised of sand (Chennai port), clay (Cochin port), and rock (Bhavanapadu port) were chosen for conducting optimised analyses. The analysis methodology involved creating four models for each site, along with IS Standard theoretical approaches. The models of the berthing structures were developed using STAAD Pro software, with detailed load calculations incorporated into the analysis. Results were presented as percentage variations in bending moments, shear force, and deflection obtained by different methods, revealing that the IS approach is comparatively non-conservative.
2025-09-16
Azzam Alosaimi
This study investigated the impact of thermal insulation placement, type and thickness on indoor air temperature (IAT), energy performance and electricity costs for a residential villa in the hot-humid climate of Jazan, Saudi Arabia. A baseline EnergyPlus model, validated against measured data from Riyadh, revealed that without insulation, IAT exceeded American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) comfort limits for 93 % of the year. Simulations of five common insulation types, including board, batt, cellular glass, fibreglass and polyurethane, demonstrated that exterior placement consistently outperformed interior installation by reducing heat transfer and infiltration. Polyurethane delivered the highest performance, achieving up to a 40,2 % reduction in annual energy use at 100 mm thickness, with diminishing returns beyond 75-100 mm. A floor-level analysis revealed that upper floors with exposed roofs required thicker insulation to counteract solar gains, whereas lower floors performed optimally with thinner layers in humid conditions. An economic analysis based on Saudi Arabia’s residential tariff structure demonstrated lifetime savings exceeding USD 79.760,00 over 20 years for top-performing configurations. The findings underscore the importance of climate- and building-specific insulation strategies to optimise both thermal comfort and long-term economic returns.
2025-09-04
Gopinath Balasubramani, Meyyappan Palaniappan
Concrete, recognized for its strength and durability, poses significant environmental challenges due to natural aggregate depletion and emissions from cement production. This study investigates the potential of Recycled Coarse Aggregate (RCA) as a sustainable alternative to Natural Coarse Aggregate (NCA) and examines the synergistic effects of hydrochloric acid (HCl) treatment and fly ash incorporation on the performance of M20 grade concrete. Findings reveal that RCA can effectively replace NCA without compromising mechanical properties; however, acid treatment enhances RCA's bond with the cement matrix, leading to improved strength and durability. Furthermore, optimal mixes achieve a 25,7 % reduction in cement content when incorporating HCl with 25 % fly ash, alongside minor reductions in coarse and fine aggregates. Experimental results show that NCA achieves the highest compressive strength of 30,7 MPa, while untreated RCA shows a strength of 25,4 MPa. With HCl treatment, RCA reaches 30,0 MPa, and the optimal mix of 1,25 M HCl and 25 % fly ash yields the best performance at 32,6 MPa due to enhanced pozzolanic effects. This research emphasizes the importance of optimizing concrete mix designs through innovative treatments and sustainable materials, contributing to environmentally friendly construction practices.
2025-09-02
Lidija Tadić, Tamara Brleković, Marija Antolović
This article introduces the New Drought Index (NDI) to a wide scientific and professional society. This index, relatively simple to apply, was published by Bonacci et al. in Croatia in 2022 and international journals in 2023. Thus far, it has been tested in many countries on four continents. The main strength of NDI is that it uses only two parameters: precipitation and air temperature for a certain time period (month, season, or year). In this research, NDI was tested on a monthly basis for two Croatian regions, continental (meteorological station Donji Miholjac) and coastal region (meteorological station Split). The results were compared with those of drought severity obtained using the Standardized Precipitation Index (SPI), Standardized Precipitation Evapotranspiration Index (SPEI), Rainfall Anomaly Index (RAI), and Aridity Index (AI). The period of analysis was between 1981 and 2022. The best correlation was between both regions' NDI and SPEI (> 0,7).
2025-07-14
Željko Šreng, Krunoslav Minažek, Marin Grubišić, Marina Jelović
This study evaluates the impact of geotextile installation on the stability of a sand embankment under the influence of water seepage. For the embankment, uniform river sand was used from the lower course of the Drava River, while a non-woven geotextile, commonly used in hydraulic engineering works was selected. Five physical models at a reduced scale were built in the HM 169 apparatus, where the geotextile was installed in different configurations. The aim of the study was to determine the effect of different geotextile configurations on the stability of embankment slopes. The models exhibited different behaviours under seepage influence, ranging from very rapid failure in the case where no geotextile was present in the embankment, gradual failure with the application of geotextile without wrapping, to stability without change when geotextile was wrapped. The behaviour observed in the physical models was then simulated with numerical models using GeoStudio software. The goal of the numerical analyses was to determine an appropriate method to define slip surfaces and identify a suitable method to account for the influence of geotextile. The positive influence of the geotextile on stability was considered using various methods implemented in GeoStudio software: 1. as a standard reinforcement element, 2. by simulating a positive contribution of the geotextile with external forces (continuous load). The standard reinforcement element did not yield satisfactory results due to the position of the geotextile relative to the predefined critical slip surface. As the geotextile wrapped around the downstream slope, continuous load proved to be a better option for simulating its effect.
2025-05-25
Abbas O. Dawood, Noor M. Shakir
This research aims to address the environmental and sustainability issues associated with traditional concrete using geopolymer concrete and PET waste as alternatives. The methodology involves performing physical tests on density and absorption, and mechanical tests on the modulus of elasticity, compression, splitting, flexure, energy absorption, and axial strain. Fine aggregates (sand) are partially replaced with 5; 10; 15; 20; and 30 % by equivalent weight percentages of PET waste particles while keeping all other proportions constant. Additionally, the ultrasonic pulse velocity is determined. Specimens were evaluated at 7 and 28 d to assess the impact of PET incorporation. Results indicate that adding PET particles alters the properties of the resulting concrete. The physical properties (density and ultrasound velocity) decrease as the PET ratios increase, and the absorption rate increases. In terms of strength, results show that the specimens containing partial substitution ratios ranging within 5-15 % present 3,49-9,09 %; 2,20-10,09 %; and 8,45-10,26 % increments in tensile, compressive, and flexural strengths, respectively, compared with the reference specimens. The results also indicate a rise in the energy absorption and axial strain of the specimens with replacement percentages ranging from 5-30 %, and the modulus of elasticity decreases as the PET content increases. The strength parameters decrease when the PET content exceeds 15 %. In conclusion, replacing 10 % of sand with PET particles in geopolymer concrete enhances strength-related properties. Specifically, the tensile, compressive, and flexural strengths of the specimens are enhanced by 20,27; 12,70; and 14,28 %, respectively, compared to the reference specimen.