This study proposes an alternative verification procedure for assessing the pullout resistance of wrap-around geotextiles in flood embankments. The research does not aim to determine the design pullout resistance for practical engineering applications directly, but rather, to evaluate the geotextile pullout force within small-scale physical models intended for conceptual-level analysis. The approach addresses the limitations of standard numerical models in capturing the actual slope failure mechanism. It also accounts for the stabilising effect of geotextile wrapping, which is often insufficiently represented in conventional analyses. The proposed approach integrates physical experiments with analytical and numerical modelling. Small-scale embankment models subjected to seepage-induced hydraulic and slope stability failure were reinforced with wrap-around geotextiles of varying anchorage lengths and wrap-around heights along the downstream toe. The observed stability or failure of the physical models was used to evaluate the analytical formulation. The analytical model is based on a comparative calculation of hydrodynamic force and geotextile pullout force. The analytically derived pullout force was implemented in GeoStudio: SLOPE/W to assess the embankment stability. A comparative assessment of the physical, analytical, and numerical results showed good agreement, confirming the reliability of the proposed verification approach. The developed analytical model, validated through numerical simulations and experimental observations, represents a useful tool for the conceptual evaluation of embankment stability mechanisms.
In the northern areas of Pakistan, the fabric mostly used for wearing purposes is polyester (polyethylene terephthalate (PET). Due to its versatile quality, concrete is the most demanding construction material. In this study, durability & mechanical properties of polyester concrete (PC) are investigated by including raw polyester fibre (PF) with varying percentages (0,0; 0,5; 1,0; 1,5; and 2,0 %). Additionally, 1% sodium carbonate is used as a cement replacement. The results reveal that the addition of 1 % polyester (PET) fibre by weight produces 25,0 and 20,6 % increases in tensile and compressive strengths, respectively. The increased percentage of fibre also significantly reduces chloride permeability, indicating improved crack resistance in concrete. However, fibre additions of 1,5 or 2,0 % may result in reduced compressive strength and increased permeability. Therefore, 1 % polyester fibre is recommended for the application of concrete tension members and mortar in external walls. Moreover, this research focuses on the sustainable use of raw polyester as a constructive approach towards addressing environmental challenges associated with conserving resources, waste disposal, and mitigating environmental pollution.
The management of large and complex construction projects, particularly the optimization of project completion time, cost, quality, and coordinated resource allocation, remains a critical challenge. This challenge becomes increasingly pronounced in projects characterized by numerous activities, strong temporal dependencies, and limited resources. The growing number of concurrent projects has intensified implementation delays, leading to increased construction costs, reduced quality, and, in extreme cases, economic infeasibility. This study proposes an efficient hybrid framework to investigate the factors influencing delay time, project cost, and quality. The results of reliability analysis showed a Cronbach’s alpha value of 0,80 for the design and engineering phase (10 factors), 0,76 for the procurement phase (15 factors), and 0,59 for the construction phase (23 factors), confirming acceptable data reliability. A comparative analysis between the quantitative index method and a metaheuristic approach, namely an enhanced harmony search (HS) algorithm, was then conducted. The results demonstrate that the HS algorithm effectively balances the time-cost-quality trade-off, achieving notable reductions in project duration and total cost while maintaining the desired quality level. The proposed framework exhibits higher convergence stability and adaptability than conventional methods, highlighting its potential as a practical decision-support tool for data-driven and sustainable management of large-scale construction projects.
The growing global emphasis on sustainable, low-carbon energy has intensified interest in biomass as a renewable substitute for fossil fuels, with torrefaction emerging as an effective thermal pretreatment for enhancing fuel properties, particularly for co-firing in coal-based power plants. This study examines the oxidative torrefaction of three widely available lignocellulosic residues sugarcane bagasse, sawdust, and rice husk processed at 200, 250, and 300 °C for 30 min under ambient air conditions to simulate oxidative environments. Fuel quality improvements and physicochemical transformations were assessed using proximate analysis, calorific value measurements, energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, and thermogravimetric analysis. The results indicate that oxidative torrefaction significantly enhances biomass characteristics by increasing fixed carbon content, reducing moisture and volatile matter, and improving calorific value. Among the materials studied, sawdust exhibited the most pronounced enhancement, attaining a calorific value of 5941,53 kcal/kg and the highest carbon concentration, followed by sugarcane bagasse, while rice husk showed moderate improvement due to its higher ash and silica content. Overall, the findings demonstrate the suitability of torrefied biomass for integration into existing coal-fired systems, supporting emission reduction, cleaner energy generation, and alignment with India’s energy transition and carbon mitigation objectives.
Construction components are in greater demand as a result of the rapid growth of the building sector. This study investigated the feasibility of using expanded polystyrene (EPS) beads in combination with silica fume to produce lightweight construction materials. The strength and weight properties were determined using different types of mixed samples consisting of bricks and concrete of the same grade. The results were compared with the standard samples and cast with EPS. EPS was used as a volumetric replacement of 0; 10; and 20 % of coarse and fine aggregate along with silica fume to increase the strength of concrete and bricks for the experiment. The results revealed that when using 10% and 20 % EPS, the unit weight of the concrete samples decreased by 9 and 16 %, whereas the compressive strength decreased by 25 and 43 %, respectively. For the bricks, the weight decreased by 10 and 19 %, whereas the strength decreased by 26 and 49 %, respectively. Cement was replaced with 7,5 and 12,5 % silica fume in various combinations with these EPS substitutes to mitigate the loss of strength. The results showed an increase in the strength of the EPS-mixed concrete increased by 9 % when pozzolanic material was used, and the strength of the brick increased by 6,5 % compared with normal samples. In the combined effectiveness analysis, the EPS used in bricks was more effective than in concrete samples. Therefore, based on the effectiveness analysis, EPS can be easily used in a moderate range of building materials.
This study aimed to elucidate the effects of incorporating basalt and banana fibres on the mechanical behaviour of ultra-high-performance concrete (UHPC). Two distinct UHPC groups were evaluated; the first group consisted of unreinforced control specimens, whereas the second group included fibre-reinforced specimens with systematically varied fibre volume fractions of 0,25; 0,50; and 1,00 % to assess the impact of fibre content. The fibres enabled a thorough assessment of their types and impact on UHPC performance. Beam-shaped specimens were cast with these fibre contents to facilitate three-point bending tests, enabling assessment of their response under flexural loading. The results conclusively demonstrate that incorporating 1,00 % basalt fibres yielded significantly improved performance compared to all other mix proportions, including those containing banana fibres or lower basalt fibre content. This outcome highlights the potential of basalt fibres as a valuable reinforcement strategy for enhancing the mechanical properties of UHPC, particularly its flexural resistance and energy-dissipation capabilities.
The present study focuses on the effect of elevated temperatures i.e., 150, 300, and 450 degrees C on the mass and compressive strength of cement mortar consisting of industrial wastes such as plastic waste, micro silica, and ground granulated blast furnace slag. Plastic waste as a sand substitute and industrial by-products such as micro silica and ground granulated blast furnace slag as a cement substitute were used in the different mix proportions of cement mortar. The plastic waste with or without supplementary cementitious materials was used in the mortar mixes. The environmental assessment and performance index of different cement mortar mixes were evaluated and compared with the conventional mortar mix. Results showed that plastic waste, micro silica, and furnace slag enhanced the residual compressive strength, whereas the wastes reduced the mass of mortar specimens. It was concluded that the use of industrial waste up to a certain extent improved the performance of the mortar mixes. The circular economy and sustainable development are embodied in this approach by conserving natural resources, minimising waste, and maintaining acceptable performance characteristics.
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.
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 phi ') 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 degrees 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 degrees 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.
In industries where thermal endurance is critical, such as metallurgy, power generation, and construction, heat-resistant concrete (HRC) represents a specialised form of concrete engineered for high-temperature applications and thermal cycling. Traditional concrete, when exposed to elevated temperatures, undergoes significant morphological and chemical transformations that lead to disintegration and a reduction in mechanical strength, as the thermal, mechanical, and deformation properties of concrete govern the response of structural elements to fire exposure. In this investigation, three distinct concrete mix designs were prepared and subjected to controlled heating, and their compressive strengths were evaluated against those of the control concrete to assess performance under thermal stress. The study also examined the composition, characteristics, and potential applications of HRC by exploring the use of various binders, additives, and aggregates aimed at enhancing thermal stability. Basalt aggregates, combined with high-temperature-resistant binders such as Portland slag cement, were employed as primary constituents. The results demonstrated that concrete containing basalt aggregates exhibited superior thermal performance compared with natural aggregates, with a binder content of 420 kg/m³ showing optimal strength retention across all curing and heating conditions. Consequently, the investigation confirmed the applicability of HRC for industrial construction environments exposed to high temperatures of 105, 350, and 700 °C.
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.
Accurate estimation of infiltration is critical for hydrological modelling, particularly in regions with heterogeneous physiographic conditions. Conventional field measurements, while reliable, are labour-intensive and spatially constrained, underscoring the need for robust predictive models. This study presents a multiple linear regression (MLR) framework for predicting infiltration rates across diverse terrains in Kerala, India, using both primary field measurements and secondary soil property data. Key infiltration influencing parameters percentage silt, clay, sand, bulk density, initial moisture content, and time were incorporated into the model, with logarithmic transformation applied to linearize the relationship. Model coefficients were derived using the least squares method in IBM SPSS, with statistical significance, multicollinearity, and overall adequacy assessed through variance inflation factor (VIF), coefficient of determination (R²), adjusted R², and standard error of estimate. Calibration was achieved by introducing an infiltration coefficient (K), determined from the ratio of field to predicted infiltration rates, with values ranging from 5,7 to 8,9 across locations. Validation using one-way ANOVA and R² analysis confirmed high predictive accuracy and model robustness. LOOCV sensitivity analysis identified time (T) as the most influential predictor, with soil texture parameters showing comparable effects. The developed MLR model provides a scalable, validated tool for infiltration estimation across varied physiographic conditions.
The high manufacturing cost of conventional fibres and the need for greener and more sustainable constructions necessitate the adoption of plant-based fibres in concrete. Previous research has shown that fibres remarkably influence the post-fire behaviour of concrete. Post-fire concrete strengths and micro-imageries are vital to the serviceability requirements of concrete. Therefore, this paper presents an experimental report on a 28-day cured kenaf fibrous high-strength concrete (KFHSC), heated from ambient temperature to 800 ºC at 100 ºC intervals, sustained for 1, 2, and 3 h, and tested after being cooled naturally to ambient temperature. The fibres were treated and examined through SEM to ascertain their interfacial properties. Test samples of concrete grade 60 were prepared using an optimum volume (0,75 %) and length (25 mm). The KFHSC's residual strength characteristics, weight, ultrasonic pulse velocity, and morphology were determined and compared with plain (unreinforced) high-strength concrete. The findings show that samples of both mixes degraded with an increase in temperature and exposure durations. However, kenaf fibre retrained crack extension at a lower temperature phase and through networks of channels within the matrices, reduced pore pressure build-up at a higher temperature phase and consequently lessened the explosive spalling of the heated concrete.
In earthquake-resistant design, structures are usually assumed to be fixed at their bases. Although in some cases this assumption may be realistic, in other cases it is neither reasonable nor conservative and the consequences can be significant. Many investigations of soil-structure interaction (SSI) in recent decades have been related to prototype frame buildings. On the other hand, relatively few investigations of SSI have considered existing structures and structures of mixed systems. This work investigates SSI in a 10-storey reinforced concrete structure built in the 1970s in Ohrid, North Macedonia. The building is part of Ohrid's 3D seismic network and is instrumented in the soil profile, foundation structure and two storeys. Thus, it provides an ideal example to investigate SSI. The interface between the soil and the structure is substituted with springs to consider the flexibility of the connection between the soil and the structure. The results of the flexible base structure are provided in terms of the reduced demands (reduced response spectra and the elongation of fundamental vibration period) and these are compared with the fixed base counterparts. The findings of this study contribute to a better understanding of SSI effects in dual systems and provide valuable insights for more accurate seismic design practices incorporating SSI.
The interaction between soil and structure, which merges geotechnical and structural engineering, plays a crucial role in seismic regions. Traditional structural design often assumes that buildings are fixed at their foundations, neglecting the influence of local soil conditions. However, accounting for soil–structure interaction (SSI) indicates greater structural flexibility, modified dynamic behaviour, and variations in the intensity and distribution of earthquake forces. These influences are especially notable in soft or moderately stiff soils, where foundation flexibility may cause increases or decreases in seismic demand. To account for these influences, American pre-codes provide detailed guidelines for incorporating SSI into structural analyses. In this study, these guidelines were applied in both nonlinear static (push-over) and nonlinear dynamic (time-history) analyses of a six-storey reinforced concrete frame structure. The analyses considered two different soil types, B and C, which were classified according to Eurocode 8, to evaluate the effect of different soil rigidity on structural behaviour. The findings, with a focus on kinematic interaction, highlighted how foundation embedment influences seismic behaviour. The results showed notable deformations in storey displacements and inter-storey drifts, as well as the formation of plastic hinges, indicating nonlinear response mechanisms. Reduced capacity curves under lower seismic forces confirmed the influence of SSI. This study underscores the necessity of incorporating SSI effects to improve seismic design accuracy and enhance the prediction of structural behaviour during earthquakes.
The quest for sustainable construction materials is driving the exploration of agricultural by-products as eco-friendly alternatives in concrete production. This study investigates the combined effect of banana fibre (BF) and banana leaf ash (BLA), derived from the Musa spp. plant, on the mechanical and durability performance of concrete. BFs at percentages of 0,25 %, 0,50 %, and 0,70 % were used as natural reinforcement to improve tensile characteristics. BLA, which is rich in silica and other pozzolanic compounds, was utilized as a partial cement replacement at varying percentages of 5 %, 10 %, 15 %, and 20 %. Experimental analysis included slump, compressive strength, split tensile strength, and flexural strength tests over different curing periods. An optimal combination of BF and BLA enhanced the tensile properties and improved resistance to environmental degradation without significantly compromising compressive strength. The findings suggest that incorporating banana waste derivatives enhances concrete performance and contributes to a more sustainable and circular construction economy.
Carbon dioxide is the primary greenhouse gas contributing to climate change. The construction industry is a main contributor to carbon dioxide emissions worldwide and must make conscious efforts towards becoming a green industry by using materials that are better for the environment. This study investigated innovative approaches to reduce carbon dioxide emissions in concrete production by replacing traditional Portland cement and paving the way to achieving net-zero-carbon concrete. Geopolymer mixes were evaluated as cement alternatives. In addition, alternative partial replacements for cement like ground granulated blast furnace slag, alongside the incorporation of various admixtures such as titanium dioxide, zinc oxide, and biochar, were tested. Tests were conducted to evaluate the compressive strength, durability, and carbon dioxide emissions. Comparisons to conventional Portland cement concrete were performed to quantify the environmental benefits of the developed concrete mixtures. The full replacement using a geopolymer was a significant step towards net-zero carbon emissions. It yielded higher strength and durability than the ordinary Portland cement concrete. The geopolymer concrete showed promising results with no curing and better results after 1 day of heat curing, which set this material steps ahead of other alternatives. Alongside the admixtures, the studied concrete model maintained the characteristics needed for structural concrete while reducing the contribution to the carbon dioxide present in the atmosphere and providing greater strength. The use of admixtures like titanium dioxide and biochar effectively enhanced geopolymer concrete while increasing its carbon dioxide absorption.
Interest in microbially induced calcite precipitation (MICP) has grown due to the demand for sustainable and energy-efficient soil improvement methods. This study explored the potential of using Sporosarcina pasteurii to enhance the engineering properties of sandy soils with varying grain sizes and relative densities. Calcium carbonate precipitation induced by bacterial activity was assessed under different bacterial concentrations (10⁷, 10⁸, and 10⁹ cells/mL) and temperatures (16 °C, 30 °C, and 45 °C). The improvements were evaluated using unconfined compressive strength (UCS) tests and microstructural analyses using SEM, EDS, and XRD techniques. The results indicated that MICP significantly increased soil strength, with the highest UCS values observed for medium and coarse sands under optimal conditions. Fine sand exhibited limited improvement owing to lower permeability, which hindered bacterial distribution. SEM and XRD analyses confirmed the presence of calcium carbonate polymorphs, such as calcite and vaterite, enhancing intergranular bonding. The optimal conditions for bacterial activity and calcium carbonate precipitation were a concentration of 10⁹ cells/mL and temperatures of 30 °C for fine sand and 45 °C for coarse sand. This research underscores the potential of MICP as a sustainable soil stabilisation technique while highlighting challenges in bacterial distribution and bonding across different sand types.
High-and low-expansivity are common in all expansive soils. Most roads are constructed on high-and low-plastic soils that can be enhanced by means of fly ash-based geopolymer, a "green cement". This paper describes the effectiveness of fly ash-based geopolymer for construction of road subgrade through laboratory experimentation, considering free swell behaviour, shrinkage behaviour, unconfined compression test, California bearing ratio, and resilient modulus. The effectiveness and feasibility of the material were characterized in terms of reduction in swelling and shrinkage and improvement in strength behaviour of soil mass. The optimized fly ash and geopolymer mixes were noted at 25 %, as observed through the microstructural analysis of soil samples. Soil plasticity plays an important role, governing the strength of soil. Low-plastic soil shows high mechanical strength compared to high-plastic soil. Fly ash geopolymertreated soil material was found to be more suitable for construction of the sub-grade or sub-base layer of flexible pavement, help to reduce conventional stabilizer, and lead to a sustainable solution.
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.
