Engineering

Abstract: Heating, Ventilation, and Air Conditioning (HVAC) systems account for 60-70% of residential electricity consumption in Oman, where extreme desert climates with temperatures regularly exceeding 45°C create substantial cooling demands. As climate change intensifies cooling requirements, optimizing HVAC control strategies has be-come critical for energy sustainability while maintaining occupant thermal comfort. This review systematically analyzes four smart HVAC control paradigms applicable to Omani residential buildings: Model Predictive Control, Deep Reinforcement Learning, Fuzzy Logic Control, and Internet of Things-based integrated approaches. We examine performance data from Oman and Gulf Cooperation Council case studies, including the GUtech EcoHaus net-zero energy building and large-scale retrofit program analyses, contextualized within Oman's policy framework. Our analysis reveals that Model Predictive Control strategies achieve energy savings of 16-40% while maintaining thermal comfort within acceptable Predicted Mean Vote ranges. Deep Reinforcement Learning-based controllers demonstrate superior adaptability to dynamic occupancy patterns with reported energy reductions of 17-23%. Case studies demonstrate realized energy savings ranging from 25-75% depending on intervention comprehensiveness and baseline building performance. These findings indicate that advanced control strategies offer significant potential for reducing residential energy consumption in extreme heat climates when integrated with high-performance building envelopes. Future work should prioritize the development of occupant-centric adaptive comfort models calibrated for extreme heat conditions, integration of distributed energy re-sources with HVAC systems, and context-specific control strategies that account for regional occupancy patterns and cultural preferences.

Abstract: Urban construction plays an important role in Ghana’s development, but it also contributes to environmental problems such as high energy use, waste generation, and resource depletion. This study examined the managerial capacity needs of built environment professionals for delivering environmentally sustainable buildings in urban projects in Ghana. A quantitative survey design was used, and a structured questionnaire was administered to 100 architects, engineers, quantity surveyors, and project managers in the Greater Accra and Ashanti regions. The data were analysed using factor analysis in SPSS, with reliability testing to confirm the consistency of the instrument. The findings showed that managerial capacity needs are grouped into four main areas: individual, organisational, industry, and state-level needs. At the individual level, stakeholder engagement, risk management, and environmental knowledge were identified as key skills. At the organisational level, firms need stronger strategies, supervision, and quality control systems. At the industry level, certification, training, and knowledge-sharing platforms were important, while at the state level, respondents highlighted the need for better regulation, streamlined permitting, and government-led training. The study concludes that improving managerial capacity is essential for mainstreaming environmentally sustainable buildings in Ghana. Strengthening training, organisational systems, industry standards, and public policy will help support a more sustainable construction sector.

Abstract: This paper presents the complete theoretical framework for a three-dimensional thin-walled beam finite element with seven degrees of freedom per node: axial displacement u, transverse displacements v and w, torsional rotation θx, bending rotations θy and θz, and warping rotation φ. The formulation rigorously incorporates flexural–torsional coupling, shear flexibility in bending and torsion, bimoment effects, and geometric non-linearity through an exact geometric stiffness matrix. The variational (weak) form is derived in full from the principle of virtual work, yielding all generalized elastic and geometric stress resultants. Equilibrium equations in strong form and natural boundary conditions follow as the Euler–Lagrange equations of the variational statement. The resulting element enables analysis of lateral-torsional buckling, second-order effects, and general 3D instability of open and closed thin-walled members.

Abstract: Three designs for broadband sound absorption by thin hard backed layers, respectively, combine synthetic porous materials and resonant cavities, embed opposed arrays of horizontal plates in a porous layer and mount multiple parallel microperforated plates in a conical shell. The measured and predicted normal incidence absorption spectra from these designs are compared with predictions for hard backed porous layers of the same thickness that either have a small number of embedded vertical and horizontal solid partitions or consist of materials derived from natural sources. The comparisons suggest that broadband sound absorption spectra comparable with those of the more complicated designs can be obtained in ways that are simpler and potentially more sustainable for manufacture and disposal.

Abstract: This study investigates the degradation of indoor environmental performance in a colonial-era school building under current tropical climate conditions and its implications for occupant comfort and cognitive function. A field study involving 30 students over 18 days was conducted, integrating environmental measurements, subjective responses, and cognitive tests (attention and working memory). Results indicate that indoor air temperature, relative humidity, and illuminance exceeded recommended standards, resulting in elevated PMV (≈1.5) and PPD (>50%), reflecting thermally uncomfortable conditions. Statistical analysis revealed significant negative relationships between thermal stress indicators (PMV and HSSI) and cognitive performance (r up to -0.94), demonstrating that increased thermal load reduces attention and working memory accuracy. In contrast, lighting showed no significant effect, likely due to uniformly low illuminance levels. These findings suggest that passive design strategies in colonial buildings are no longer sufficient under current climatic conditions and may compromise learning performance. The study highlights the need for adaptive design interventions to maintain indoor environmental quality in tropical educational buildings.

Abstract: Ultra-high-performance concrete (UHPC) possesses excellent mechanical properties and durability, but its inherent brittleness significantly limits its structural application under complex loading conditions. This research proposes a composite reinforcement system consisting of steel wire mesh (SWM) and basalt fiber mesh (BFM) based on the composite mesh configuration. Through study of single mesh and composite mesh configurations mixed with 1 vol.% steel fibers on the tensile and flexural properties of UHPC, the multi-scale reinforcement mechanism was revealed. This research designed 11 tensile specimens and 12 flexural specimens, employing a layered casting process to ensure equidistant distribution of the meshes. The results indicate that the SWM significantly increases the peak load and induces strain hardening behavior, while the BFM exhibits no strain hardening response when used alone. Among the layered composite mesh configurations, the steel mesh outer layer (SXS) outperformed the basalt mesh outer layer (XSX), exhibiting the most optimal combined values for the hardening index (I = 1.02) and deformation index (R = 0.91). After incorporating 1% steel fibers, the SXS1+SF1 combination achieved a synergistic improvement in both strength and toughness with energy dissipation during the strain hardening stage reaching 43375.5 N·mm. This composite reinforcement system provides a design-oriented structural approach for achieving a synergistic enhancement of both strength and ductility in UHPC.

Abstract: Hot-arid residential buildings experience persistent cooling demand and increasing material intensity, yet most building-performance studies prioritize operational energy while insufficiently integrating life-cycle carbon and material sufficiency into envelope evaluation. This limits the ability to distinguish between performance gains achieved through passive design efficiency and those dependent on increased material input. This study investigates the interaction between material sufficiency, energy use, and life-cycle carbon in residential buildings across three representative hot-arid climates: Riyadh, Abu Dhabi, and Doha. A Pareto-informed multi-criteria evaluation framework was applied using a standardized mid-rise residential prototype to assess predefined envelope design strategies under consistent operational conditions. Dynamic energy simulations were conducted in DesignBuilder/EnergyPlus, while embodied carbon was quantified through a consistent material inventory approach. Baseline energy use intensity (EUI) values reached 64.98, 83.13, and 93.67 kWh/m²·year for Riyadh, Abu Dhabi, and Doha, respectively, reflecting increasing cooling demand from inland dry to humid coastal conditions. Envelope optimization reduced EUI to 47.33–72.40 kWh/m²·year, while embodied carbon ranged from 40,761.2 to 57,146.2 kgCO₂-eq per configuration. Reduced window-to-wall ratio strategies consistently achieved the most balanced performance across all climates, whereas high-glazing configurations increased energy demand, carbon emissions, and material intensity. The study operationalizes a sufficiency-oriented evaluation perspective that supports climate-responsive envelope decision-making by integrating operational and material performance within a unified comparative framework.

Abstract: Buildings account for a major share of global energy demand and operational carbon emissions, underscoring the importance of climate-responsive façade design in sustainable architecture. Façade parameters such as glazing ratio, shading systems, and glazing properties strongly influence thermal performance of buildings; however, most optimization studies remain confined to single climates and rarely provide practical design guidance. This study introduces an AI-assisted optimization framework for evaluating façade performance across four contrasting climate zones: Abu Dhabi (hot-arid), Singapore (hot-humid), Athens (Mediterranean), and Berlin (temperate). A standardized five-story residential prototype was modeled in DesignBuilder using the EnergyPlus simulation engine. Window-to-Wall Ratio, orientation, shading depth, and glazing type were optimized using the Non-Dominated Sorting Genetic Algorithm II to minimize Energy Use Intensity (EUI) and operational CO₂ emissions while maintaining thermal comfort through ASHRAE 55 discomfort-hour constraints. The optimized solutions reduced EUI by approximately 54% in Abu Dhabi, 56% in Singapore, 43% in Athens, and 40% in Berlin relative to baseline conditions. A post-optimization AI-assisted rule-based interpretation layer applied to identify recurring façade parameter patterns among Pareto-optimal solutions revealed a systematic transition from low-glazing, deep-shading solutions in hot climates toward higher glazing ratios with limited shading in temperate environments. These findings indicate that façade optimization is climate-dependent and that AI-assisted workflows can support interpretable, performance-driven architectural decision-making.

Abstract: The paper addresses the intersection between modern built heritage preservation and Climate-aided Design (CADe) processes in fragile coastal Mediterranean contexts. The study focuses into Beirut city in Lebanon, part of the EMME region and considered a climate change hotspot facing extreme challenges. Rapid urbanization and socio-political instability, especially during the 20th century, combined with the effects of climate change, undermined the city’s ability to mitigate and adapt to future climate change scenarios. Moreover, Beirut’s modern built heritage faces a constant threat of demolition due to the absence of protective legislation and real-estate development ambitions. The hypothesis is that the integration of climatic data and regenerative design with modern cultural heritage classification frameworks can aid the process of the preservation and drive a more adaptive and inclusive approach to urban regeneration. To test this hypothesis, a multi-scalar case-study-based methodology is adopted using a combination of digital tools to assess and analyze the current and future impacts of climate change on two main case studies. First, The Saint George Hotel, one of the first reinforced concrete recreational buildings in the city, built during the French Mandate (1923-1946), vulnerable to sea-level rise, flooding and demolition. Second, the Beirut City Center “The Egg”, a Brutalist structure built during Beirut’s modernist “golden era”, prone to structural deterioration and inutility. The main objective is to highlight 20th century-built heritage as part of Beirut’s spatial narrative worthy of conservation and rehabilitation by analyzing their capability to adapt, mitigate, or benefit from future environmental risk. Ultimately, the study explores their potential to catalyze climate-resilient urban regeneration practices in the city.

Abstract: Crack opening and reinforcement stress are two complementary indicators of the service state of reinforced concrete hydraulic structures, yet they are often predicted separately.This study develops a data-driven multi-task temporal fusion framework for joint 48 hahead prediction of dam crack responses and rebar stress using multi-source monitoring data. The measured data comprise five crack-monitoring series, five rebar-stress series,local temperature channels, reservoir water level, antecedent rainfall, and an auxiliary environmental signal from 2021-03-11 to 2025-03-06. Target responses are aligned only at commonmeasuredtimestamps; no synthetic target observations are introduced. A residual multi-task temporal fusion network (MTTF-Net) is proposed with a shared Transformer 10 encoder, attention pooling, task-specific decoders, and a response-continuity regularization term. The model is compared with persistence, Ridge regression, random forest, Extra Trees, XGBoost, and GRU baselines under a chronological train/validation/test split. On the independent test period, Ridge regression obtains the lowest overall RMSE (2.2968), whereas MTTF-Net provides the lowest crack RMSE (0.0141), the lowest overall MAE (1.0035), and the second-best overall RMSE (2.3813). These results indicate that the monitoring data contain a strong linear autoregressive component, while multi-task temporal fusion improves nonlinear crack-response prediction and remains competitive for stress forecasting. The source code is prepared as a public implementation package, whereas the measured monitoring dataset is subject to data-owner restrictions.

Abstract: Building Information Modeling (BIM) represents a building as a static snapshot of the model’s state. The IFC standard does not define a formal mechanism that would link the same physical element across successive phases of a building’s life cycle. Design, construction, and operation are recorded in separate IFC files, and the same element is assigned different GUIDs in each. The result is fragmentation of the element’s identity, loss of the history of property changes, and the inability to formulate cross-phase queries. This paper proposes the BIM-Phase ontology, based on the fundamental DOLCE ontology, which solves this problem by introducing a distinction between a building element as an endurant and its life cycle phases as perdurants. The ontology comprises nine classes, six object relations, and six axioms expressed in OWL 2 DL. Phase properties and relations are represented using a reification pattern, which maintains full compatibility with the expressiveness of OWL 2 DL. The ontology was validated using the example of a single-family residential building developed in Autodesk Revit. Three structural elements (external wall, floor slab, column) were tracked across three phases of the life cycle. Eight competency questions covering scalar, constitutional, and mereological changes were defined and mapped to ontology constructs, confirming that BIM-Phase enables the recording of changes and the formulation of cross-phase queries that are impossible in classic IFC.

Abstract: Earth blocks are attractive for low-cost housing because they use local soil, require less firing energy, and can provide good thermal mass, but their adoption in humid tropical regions is limited by moisture sensitivity. This review examines how agricultural waste ash stabilizers, with emphasis on palm kernel shell ash and related pozzolanic residues, influence moisture durability, dry/wet compressive strength behavior, and practical suitability of earth blocks for affordable housing. The paper synthesizes evidence from compressed earth block literature, pozzolanic material standards, and studies on ash-modified earthen masonry. It argues that wet-to-dry strength retention is a more realistic durability indicator than dry compressive strength alone because low-cost walls are exposed to wind-driven rain, capillary rise, damp surfaces, and imperfect maintenance. The review shows that ash stabilizers can improve particle bonding and pore refinement when properly processed, proportioned, compacted, and cured, but excessive ash, poor soil selection, or inadequate detailing can increase water absorption and reduce field reliability. The paper proposes a moisture-durability framework connecting material chemistry, block production, wall detailing, and tropical housing performance. It concludes that agricultural waste ash stabilized earth blocks are promising only when laboratory strength gains are tied to water-resistance testing and moisture-conscious architectural detailing.

Abstract: Disputes over change orders on construction projects often arise due to varying interpretations and priorities of the key stakeholders, namely the owners, designer and contractor. This problem is particularly evident in the flourishing construction sector of the Kingdom of Saudi Arabia due to the delay of large-scale projects. A significant reason for these delays is huge claims on changes orders and traditional means of resolution such as litigation and arbitration are not able to yield timely resolutions. These challenges highlight the need to better manage and assess the impacts of change in a more proactive manner. This research proposes the BIM-based framework which offers the solution to the above-mentioned challenges through the creation of the Integrated Virtual Environment. The setup involves linking Revit for 3D modelling with Navisworks for coordination and visualization, and Primavera for scheduling and cost control into a seamless network. This link allows project information to be displayed in an orderly manner. Furthermore, any changes in design will be connected to the effect on time and cost. In this virtual environment, the framework aims to capture and visualize the effects of change orders in terms of schedule delays and cost overruns. This approach helps the stakeholders to trace how the changes are spreading in different dimensions of the project providing a clearer and common understanding of what changes those will bring. Having more light helps with better conversations, helps with discussions at the start, and helps avoid claims. The overall findings suggest that the combined use of BIM and project management tools may create a consistent virtual platform for the analysis of change orders and their impacts on time and cost. Through a real case study, the framework is developed and validated to showcase its practical capability of aiding decision-making, reducing disputes, and improving overall project performance. The effective management of change is vital in minimizing delays and facilitating better project delivery, especially in the fast-growing construction industry of Saudi Arabia.

Abstract: This paper presents OSI4IOT, an open-source software platform designed to support the integration of sensor-driven Internet of Things (IoT), Asset Information Modelling (AIM), Geographical Information Systems (GIS), and data-driven analysis within a Digital Twin (DT) framework. The platform provides a modular architecture for connecting heterogeneous data sources and enabling the coupling between physical assets and numerical models. In particular, it supports the integration of Finite Element Method (FEM)-based structural models for simulation and comparison with monitored responses. A case study involving a structural frame is used to demonstrate the platform workflow, including data acquisition, model execution, and result visualisation. The results are used to assess the consistency between analytical, numerical, and monitored responses under varying loading conditions. The paper focuses on the system architecture and the coupling strategy between data acquisition and simulation components within an open-source environment.

Abstract: In tropical island cities, the combined pressures of rapid high-density urbanization and year-round hot-humid climates make the pedestrian-level wind environment a critical determinant of outdoor thermal comfort and cooling performance. Focusing on Haikou, a tropical island city, this study optimizes building layouts on commercial plots under constant development intensity. A Pedestrian-level Cooling Performance Index (PLCPI) was constructed, prioritizing summer cooling and winter wind control through an AHP-EWM combined weighting method. The index integrates maximum pedestrian-level wind speeds and amplification factors to evaluate 65 layout configurations, including detached, row, perimeter, and courtyard types. The results reveal a nonlinear relationship between building count and cooling performance. Single-building layouts achieve the highest mean PLCPI (2.367), three-building layouts the lowest (1.825), prone to ventilation stagnation, and four-building layouts show a performance rebound (2.271) with stable efficiency. Crucially, spatial enclosure form is the decisive determinant under a constant building count: the optimal two-building layout B-8 (PLCPI=2.456) surpasses the best single-building layout A-2 (2.419), demonstrating that well-designed dispersed layouts can outperform centralized ones. This study proposes a dual-season adaptive evaluation framework for tropical commercial plots and reveals the nonlinear mechanism between building quantity and cooling performance, providing a scientific basis for fine-grained urban design in tropical island climates.

Abstract: The reconstruction of Mosul after 2017 has produced a residential landscape in which design intent systematically fails to survive construction. While existing scholarship examines the materiality and symbolism of post-conflict façades, it neglects the process conditions under which aesthetic specifications are overridden. This study examines the relationship between form and materiality in contemporary Mosul residential architecture through a mixed-methods design: formal visual analysis of twelve recently completed façades and a structured survey of forty-five practising architects. Visual analysis reveals a sophisticated design language of controlled complexity (orthogonal massing articulated through contrasting materials) that is rarely realised in built form. Survey data show that architects are excluded from construction supervision in seventy-six per cent of projects, with client intervention affecting seventy per cent. Architectural oversight emerges as the primary determinant of aesthetic integrity: projects most consistently achieve material–form coherence where architects retain supervisory authority, whereas exclusion produces four distinct pathologies: material substitution, execution degradation, language override, and ornamental hollowing. The study advances the concept of an aesthetics of interruption, understood as the systematic degradation of designed form–material relationships through the fragmentation of professional authority. It demonstrates that aesthetic degradation in post-conflict reconstruction stems not from design incapacity but from broken process structures. Preserving architectural quality requires contractual frameworks mandating designer supervision and material-substitution protocols that protect design intent.

Abstract: The pressing need to minimize cement-related CO₂ emissions attracted the search for agricultural waste ashes as supplementary cementitious materials (SCMs). Agro-waste ashes, rich in silica and alumina, are promising cementitious materials. However, prior researchers reported inconsistent chemical compositions and physical properties due to differences in calcination methods. This systematical review proofed the impact of calcination temperature on the chemical composition, physical properties and pozzolanic performance of agricultural waste ashes. Systematic Literature Review (SLR) following PRISMA protocols, with published articles retrieved from Scopus, Web of Science, Wiley Online Library, and Google Scholar (2014–2025) was used for the study. Using keywords, 524 published articles were first identified; after screening and eminence evaluations, 50 articles met the inclusion criteria. Data was obtained mainly on calcination methods, chemical compositions, physial properties and compliance with standards such as GS 1118 (2016) EN 197-1 (2011) and SANS 50197-1. Comparative analysis disclosed constant deficiencies in CaO (0.91–25.80%) and extreme SiO₂ (40–63%) and Al₂O₃ (10–42%) contents, particularly with open-air burning. The findings emphasized 600–700°C for 90–120 minutes as the best manufacturing window for standard-conformity of ashes derived from agro-waste materials. This review highlighted the importance of controlled calcination, identified research gaps, and provided evidence-based principles for manufacturing SCMs in construction.

Abstract: Moisture content is a critical parameter influencing the durability, structural performance, and maintenance of timber structures. However, current building inspection practices often rely on subjective interpretation, resulting in inconsistent assessment outcomes and ineffective maintenance decision-making. Despite the availability of various moisture measurement techniques, a standardized framework for interpreting moisture levels in relation to timber condition is still lacking. This study presents a structured review and synthesis of moisture content thresholds reported in the literature and proposes a standardized classification framework for timber defect assessment. The findings indicate that moisture content levels can be systematically categorized into four condition states dry, moderate, poor, and critical for each associated with specific maintenance actions. The proposed framework provides a practical linkage between moisture measurements and condition-based maintenance strategies, enabling more consistent and reliable inspection practices. The study contributes by transforming dispersed moisture-related data into a unified and actionable classification system, serving as a decision-support tool for building inspectors and maintenance practitioners. The proposed framework enhances the implementation of condition-based maintenance by reducing subjectivity and improving the accuracy of timber condition assessment.

Abstract: Moisture damage in buildings has conventionally been discussed mainly in relation to winter condensation in cold climates. In hot-humid buildings, however, deterioration develops under different boundary conditions, including persistently warm and humid outdoor air, frequent rainfall, air-conditioning operation, air leakage, and limited drying after wetting. Climate change is increasing atmospheric moisture loading and weakening nighttime recovery. These changes make hot-humid moisture risks more consequential not only in established hot-humid regions, but also in regions shifting toward more persistently humid climates. This review examines moisture damage in hot-humid buildings as a coupled problem linking climate change, building-envelope moisture response, risk assessment, microbial implications, and building adaptation. Representative scenarios include biological contamination on exterior surfaces, summer condensation and moisture accumulation within envelope assemblies, localized dampness at indoor surfaces and behind furniture, moisture stagnation in semi-enclosed spaces, and material deterioration or performance loss. These phenomena are interpreted not as isolated defects, but as manifestations of drying deficit. The review discusses climatic drivers, building-physics mechanisms, and major moisture and mold risk indices, including the Fungal Index (FI), the VTT Mold Index, isopleth-based approaches, Mold Resistance Design (MRD), and the Dose-Response Simple Isopleth for Mold (DR-SIM). It also highlights implications for envelope design, retrofit, ventilation, dehumidification, and operation. Overall, moisture damage in hot-humid buildings is best understood as the outcome of climate-driven drying deficit.

Abstract: Programmed conservation of heritage buildings requires assessment tools capable of iden-tifying vulnerabilities in a systematic and decision-oriented manner. This study proposes and applies a methodology for calculating the vulnerability index of the National Theatre of Costa Rica, with the aim of establishing a technical baseline for monitoring, prioritizing interventions, and supporting long-term conservation management. The method struc-tures vulnerability through four dimensions (systems, environment, use, and urban pres-sure), each subdivided into specific risk variables weighted through the Analytic Hierar-chy Process (AHP) and pairwise comparison matrices. The building was assessed through 33 spaces grouped into 17 zones, based on two on-site evaluation campaigns, and the re-sults were consolidated into a global assessment matrix. The findings indicate an overall low vulnerability index for the building (1.391), with similarly low values recorded for systems (1.549), use (1.450), environment (1.268), and urban pressure (1.198). However, the South Façade (1.824) and the Foyer (1.778) reached medium vulnerability levels, while several additional spaces were close to that threshold. The results suggest that use-related conditions exert the greatest influence on the overall index, whereas systems-related is-sues—particularly electrical installations—remain a relevant field for intervention. The study supports the applicability of the proposed method as an objective instrument for programmed conservation of built heritage.