Rockfill dams draw nearly all of their shear resistance from the internal friction angle (ϕ) of the fill, yet design practice still treats ϕ as a fixed input and rarely traces how its variability propagates into seismic safety and construction cost. This study quantifies that propagation and asks whether the resulting safety–cost trade-off can be resolved numerically rather than through heuristic factors of safety. Limit equilibrium analysis, supported by the nonlinear Hoek–Brown strength description and cross-checked against slice-based solutions in GEO5 (Bishop, Fellenius–Peterson, Spencer, Janbu, and Morgenstern–Price), generated a 42-point parametric data set spanning ϕ = 30–60° and horizontal seismic coefficients kh = 0–0.4. Monte Carlo simulation with 10,000 realizations quantified the uncertainty in the factor of safety (FS); Newmark sliding-block analysis estimated permanent seismic displacement; four regression models were trained as surrogates for the area-ratio response; and genetic algorithm and NSGA-II searches explored the design space. Raising ϕ from 30° to 60° increased FS by 96
Road traffic crashes (RTCs) remain a major public safety challenge in Ghana, with fatality rates in regions such as the Central Region continuing to rise despite ongoing road safety interventions, including infrastructure upgrades and public education campaigns. This persistence suggests that long-term patterns and temporal changes in regional crash occurrence remain insufficiently understood. This study analysed RTC patterns in Ghana’s Central Region from 2014 to 2024 using historical crash data from the National Road Safety Authority. Descriptive statistics and Poisson regression were used to identify temporal trends. The analysis examined crash frequency, severity, vehicle involvement, pedestrian casualties, and the demographic characteristics of fatally injured persons. The findings revealed a steady increase in crashes over the study period, with total crashes rising by 38
This study investigates the mitigation of excessive vibrations in two adjacent elevated storage tanks exposed to sequential nonstationary seismic excitations with time-varying frequency content. The coupling between the adjacent tanks is achieved through a sky-bridge structure that acts as a nonlinear mechanism, which is considered as a system comprising two nonlinear springs, two linear viscous dashpots, and an attached mass element, collectively referred to as a nonlinear energy sink (NES) mechanism. To describe the vibrational response, each tank is formulated using an equivalent multi-degree-of-freedom representation. A parametric analysis is conducted to investigate how the main NES parameters affect the dynamic response of coupled tanks under excitation input. Numerical simulations are performed using a mathematical model of earthquake ground motions consisting of two frequency-varying sequences as representative dynamic inputs. A sensitivity analysis of the mass ratios, nonlinear stiffness, and damping elements is carried out to determine their suitable values to achieve significant attenuation of excessive vibrations. The vibration suppression performance of the NES is investigated and quantitatively compared with that of a tuned mass damper (TMD) absorber. Subsequently, particle swarm optimization (PSO) is applied using a defined objective function to select the optimal NES parameters to improve vibration mitigation. Findings reveal that the connector structural element significantly improves the dynamic performance of the entire system. Accordingly, this configuration provides structural benefits, and reduces seismic responses more effectively than the uncontrolled case.
The sustainable use of agricultural and industrial waste materials in concrete requires quantified experimental evidence and interpretable prediction tools for engineering decision-making. This study evaluated concrete containing sugar, cow bone ash, groundnut shell ash and limestone powder and developed interpretable strength models. A 1:2:4 mix used 317 cementitious material, 739 fine aggregate and 1380 coarse aggregate at 0.50 water-to-binder ratio, with 0 to 30
Recurring roadside landslides along Himalayan highway corridors pose a critical threat to infrastructure and livelihoods, yet paired investigations of distinct co-located failure modes remain scarce. This study investigates two active landslides, Khamvitta and Lete Khola, along the Kaligandaki Corridor (NH-48), Nepal, with Khamvitta directly tested in the field and laboratory and Lete Khola assessed by geophysics alone. Two-dimensional Electrical Resistivity Tomography (ERT) was deployed at both sites; Standard Penetration Tests, Dynamic Cone Penetration Tests, and laboratory characterisation were additionally conducted at Khamvitta, while Lete Khola relied solely on a single ERT profile, with shear strength parameters drawn from published analogues to inform limit equilibrium modelling. Low-resistivity zones (< 100 Ωm) were interpreted as saturated clay-silt horizons and validated against borehole data at Khamvitta. Monsoon-season SEEP/W-coupled SLOPE/W modelling gave a factor of safety (FOS) of 1.071 at Khamvitta and two critical surfaces at Lete Khola, FOS = 0.724 (upper) and 1.298 (lower), confirming groundwater-induced effective stress reduction as the principal destabilising mechanism. Mitigation comprising subsurface drains, anchored RCC walls, gabion walls, soil nailing with 3D mesh, and slope re-profiling improved the FOS to 1.847 at Khamvitta, 1.378 (upper), and 2.357 (lower) at Lete Khola respectively. The study demonstrates that comparable hydrological forcing produces fundamentally different failure modes, shallow rotational failure in phyllitic colluvium at Khamvitta and compound translational failure in cohesionless alluvium at Lete Khola, governed by contrasting lithology, slope geometry, and anthropogenic modification; the Lete Khola interpretation is a literature-constrained conceptual model. These findings offer transferable guidance for roadside slope management across trans-Himalayan corridors.
Cement Grouted Bituminous Macadam (CGBM) is a semi-flexible pavement material that combines the benefits of both flexible and rigid pavements. While CGBM demonstrates excellent rutting resistance compared to conventional bituminous mixes, its fatigue resistance remains inferior. This study investigates the performance of cold mix-CGBM, emphasizing improvements in fatigue behavior. By utilizing an emulsion-based aggregate skeleton, the short-term ageing associated with hot mix aggregate skeleton preparation can be minimized. The cementitious grout for the CGBM was optimized based on its flowability and strength characteristics and was used in both conventional (Asphalt-based) and emulsion-based CGBM. A comprehensive evaluation was conducted to assess various properties, including Marshall stability, compressive strength, Indirect Tensile Strength (IDT), Resilient modulus (MR), Cantabro abrasion, Hamburg Wheel Tracking Test (HWTT), and 4-point flexural beam fatigue tests. Experimental results show that both bitumen-based (B-CGBM) and emulsion-based (E-CGBM) mixes satisfied the mechanical and performance criteria outlined in IRC SP: 125:2019. Notably, the fatigue life of E-CGBM was found to be 1.4 to 2.0 times higher than that of B-CGBM. The energy analysis concluded that the E-CGBM required 29
The COVID-19 pandemic substantially altered travel demand, traffic volumes and driving conditions, yet its implications for older drivers’ crash characteristics across different pandemic phases remain insufficiently understood. This study examines changes in crash involvement patterns among drivers aged 65 and older before, during and after the COVID-19 pandemic using Alabama crash data from 2018 to 2022. The modelling results revealed a high degree of temporal stability in older-driver crash profiles, suggesting that the pandemic did not fundamentally alter the underlying mechanisms driving crash risk. Across all periods, a persistent high-severity crash profile involved single-vehicle crashes in rural and open-country settings, male drivers, speeding, drowsy driving and seat belt non-use, resulting in major injuries. In contrast, urban rear-end and sideswipe collisions were largely low severity and often involved older female drivers. A distinct COVID-specific crash profile emerged involving employed drivers, longer travel distances and elevated injury severity, but did not persist post-COVID.
This study examines the steel-concrete bond characteristics of self-compacting lightweight concrete incorporating crushed coconut shell (CS) as a complete replacement for conventional coarse aggregate. Despite growing interest in coconut shell concrete (CSC) as a sustainable construction material, its bond behavior with steel reinforcement — a critical parameter for structural applications — remains insufficiently explored. Pull-out tests were conducted on cylindrical specimens (100 mm diameter × 200 mm height) using twisted steel bars of 8-, 10-, 12-, and 16-mm diameters, across two CSC mixes (SCCSC1 and SCCSC2) and a control mix (SCCC), monitored up to 90 days. Results demonstrated that bond strength improved consistently with increasing compressive strength and concrete age, with fly ash addition likely driving continued strength gain beyond 56 days. Conversely, bond strength decreased as bar diameter increased, though CSC mixes exhibited comparatively lower percentage reductions than the control. At 28 days, bond strengths for CSC mixes ranged from 3.95 to 6.52 N/mm², representing 19.3–30.7
This study proposes an experiment-driven machine learning (ML) framework to address experimental limitations in estimating compressive strength within a controlled experimental domain of locally sourced fiber-reinforced concrete (FRC). Concrete mixes incorporating 1, 2, and 3
This study develops a simulation-based surrogate modeling framework for predicting the structural response of space frame structures under predefined geometric, loading, and damage scenarios. The contribution lies in integrating a space-frame-specific parametric modeling workflow with Grasshopper–Karamba3D finite element analysis to generate 28,297 labelled configurations and evaluate machine-learning models for multi-output response prediction. The input variables include member geometry, loading conditions, and prescribed damage-location/radius parameters, while the outputs are total structural mass and maximum displacement. XGBoost, LightGBM, CNN, LSTM, MLP + LSTM, and a fixed equal-weight CNN–LSTM ensemble were compared using the same held-out test set and consistent metrics. The CNN–LSTM ensemble achieved the strongest overall R² and RMSE performance, predicting mass with R² = 0.9985 and RMSE = 0.9278 tons, and displacement with R² = 0.7542 and RMSE = 1.9997 cm. However, the ensemble did not dominate every metric, and the results show that gradient-boosted tree models are strong baselines for structured tabular finite element data. The high mass accuracy mainly reflects the geometry- and material-governed nature of the mass target, whereas displacement prediction is the more demanding and SHM-relevant task. The framework is positioned as a computational tool for rapid simulation-based scenario assessment, not as an inverse damage-localization or field-deployment-ready SHM system. Operational monitoring and inverse damage identification from measured response data remain subjects for future work.
Dense basalt is widely used in construction, but evaluations based on isolated properties may not adequately capture moisture sensitivity, elastic response, and brittle-strength variability. This study establishes an integrated engineering baseline for dense basalt sampled from a quarry within Harrat Rahat, approximately 45 km south of Madinah, Saudi Arabia. ASTM-based testing was used to determine bulk density, water absorption, bulk specific gravity, compressive strength, flexural strength, flexural modulus, modulus of rupture, and compression- and shear-wave velocities under dry and 48 h water-immersed conditions. Mean dry compressive strength was 146.76 MPa, and the preliminary 5
Adhesive anchors are widely used in structural and geotechnical applications, yet design and qualification procedures focus almost exclusively on fully cured systems. Existing reviews address anchor behaviour under mature conditions but do not synthesise the early-age period when anchors are loaded in construction and mining settings. This systematic review provides a comprehensive, multidisciplinary synthesis integrating curing kinetics, bond-strength development, shear and pry-out responses, environmental sensitivity, and modelling limitations for the early-age window (0 to 24 h post-installation) of adhesive anchors. Following PRISMA 2020 guidelines, 54 peer-reviewed studies published between 2010 and 2025 were synthesised across civil engineering, polymer science, and rock reinforcement research. At 20 °C, tensile bond strength reaches 25–60
This study investigates the alkali activation of thermally treated Moroccan yellow clay derived from phosphate mining residues and natural volcanic pozzolan from the Middle Atlas as sustainable aluminosilicate precursors for geopolymer binder production. Following calcination, calcined yellow clay (YCC) and calcined pozzolan (CP) were combined in different proportions, while all activation parameters were kept constant to isolate the influence of precursor composition on phase evolution, microstructure development, and mechanical performance. Mineralogical and microstructural analyses reveal that geopolymerization is strongly governed by the CP/YCC ratio under fixed activation conditions. XRD results indicate the destabilization of reactive aluminosilicate phases and the formation of amorphous binding products associated with C-A-S-H/N-A-S-H-type gels, whereas persistent pyroxene-related crystalline phases in CP exhibit limited reactivity and increasingly act as inert structural components at higher replacement levels. SEM observations confirm a progressive transition from dense and homogeneous matrices to more heterogeneous and porous microstructures with increasing CP incorporation. This hierarchical evolution directly governs compressive strength, with the optimum formulation (90 wt
Rapid urbanization and intensifying climate extremes are increasing pressure on conventional urban drainage systems, accelerating interest in digital transformation. Yet how such transformation unfolds in practice, particularly in medium-sized cities, remains poorly understood. Using Lianyungang City, China, as an illustrative case, this study examines stakeholder perceptions of the socio-technical conditions associated with its digital drainage transformation. Drawing on a structured questionnaire survey of drainage professionals, the analysis assesses stakeholder perceptions of system performance, awareness and expectations of digital technologies, governance readiness, and stage-specific barriers. The results reveal strong support for digitalization but persistent constraints. At the initiation stage, progress is limited by aging infrastructure, shortages of interdisciplinary expertise, and financial constraints. During implementation, socio-technical misalignment, legacy-system incompatibility, fragmented data governance, and weak operation and maintenance capacity dominate. Governance limitations are a perceived limiting factor on scaling digital initiatives, while transparency and public participation remain underprioritized. The study advances a capacity-oriented understanding of digital drainage transformation and offers policy insights for medium-sized cities.
The out-of-plane behaviour of unreinforced masonry (URM) walls is commonly assessed using formulations developed for planar elements, despite the widespread use of curved masonry in architectural and historical structures. This study investigates the influence of geometric curvature and mortar properties on the out-of-plane flexural response of URM walls through an integrated experimental-numerical framework. Material characterization revealed substantial variability in locally manufactured clay bricks, with elastic modulus exhibiting coefficients of variation of up to 77
Concrete durability is strongly affected by microcracking, which facilitates the ingress of water and chloride ions and accelerates deterioration. Cellulose fibers represent a sustainable alternative to synthetic reinforcement; however, their hydrophilic nature and residual lignocellulosic components may limit their effectiveness in cementitious matrices. This study comparatively evaluates untreated and NaOH-treated cellulose fibers at volumetric dosages of 0.5
The global construction industry’s transition to a Circular Economy (CE) requires innovative structural solutions, especially demountable connections, which enable component reuse and improve resource efficiency. This review synthesizes recent advances in demountable connection technologies and examines how they support Design for Deconstruction (DfD) across structural typologies and materials. First, it discusses the design and structural behavior of dry joints, with emphasis on bolted connections, enabling rapid assembly and reversibility in precast concrete, modular, and tubular steel buildings. The paper then critically analyses demountable shear connections in composite systems, including Steel-Concrete (SC) and Ultra-High-Performance Concrete (UHPC) beams, focusing on capacity, stiffness, ductility, and reusability after repeated disassembly and reassembly. Reversibility challenges in hybrid composites, notably Timber-Concrete Composite (TCC) systems, receive particular attention. Emerging shear-transfer solutions, such as notched connections, are reviewed for maintaining structural performance while facilitating disassembly. The conclusions highlight key barriers, achieving performance parity with monolithic systems and standardizing component reuse, and outline research priorities needed for widespread adoption of demountable structural systems in a sustainable built environment.
Uncontrolled and rapid industrialization poses significant threats to environmental sustainability in developing countries, particularly within newly established economic zones. Addressing the limited predictive assessments of rapidly expanding industrial zones in Bangladesh, this study integrates historical environmental change analysis with machine learning–based projections to establish linkages between future land-use transitions and their associated ecological and thermal stresses. The environmental impacts of industrial expansion in the Meghna Industrial Economic Zone (MIEZ), Bangladesh, were assessed through changes in land use and land cover (LULC), normalized difference vegetation index (NDVI), normalized difference water index (NDWI), land surface temperature (LST), and urban heat island (UHI) intensity, together with predictions of future conditions under continued growth. Landsat 8–9 images (2018–2025) were used to map LULC, NDVI, NDWI, LST, and UHI, while a Cellular Automata-Artificial Neural Network (CA-ANN) model was used to predict future conditions (2029 and 2033). Results show that built-up land increased nearly fourfold from 2018 to 2025, while vegetation and surface water declined. At the same time, warmer areas expanded, with LST above 22 °C covering more than 33
The decarbonization of transport infrastructure has intensified interest in the valorization of Solid Waste Materials (SWM) as secondary resources in civil engineering. While extensive research has consolidated low-carbon and circular solutions for road pavements, the specific context of railway infrastructure – including ballast, sub-ballast, sleepers and auxiliary track layers – remains comparatively fragmented and under-synthesized. This study presents a comprehensive review of global research on the application of SWM in railway infrastructure. Following PRISMA 2020 guidelines, 131 peer reviewed studies published between 2000 and 2025 were identified from Scopus and systematically reviewed. The scientometric analysis revealed a marked acceleration in publication activity after 2018, with Australia, China, the United Kingdom and Brazil emerging as the most active contributors. Ballast and sub-ballast applications represented the predominant research focus, while steel slag, recycled aggregates, rubber waste and mining residues were the most frequently investigated waste streams. The reviewed literature indicates that industrial by-products, recycled aggregates, polymeric wastes and mining residues can achieve mechanical, durability and functional performance comparable to conventional materials when appropriately engineered and verified against railway performance requirements. Scientometric mapping shows a rapidly expanding research field structured around (i) geotechnical performance and degradation mechanisms, (ii) vibration and noise mitigation through resilient inclusions, and (iii) sustainability assessment through life-cycle methods. Despite encouraging outcomes, gaps persist regarding long-term field performance, environmental risk control, harmonization of railway standards, and the integration of digital tools for lifecycle management. The findings support the strategic role of railway infrastructure as a large-scale and long-term sink for solid waste valorization aligned with circular economy strategies and low-carbon transport systems.
