Journal of Architectural Engineering

Modular construction became a preferred option for building medical and quarantine facilities during the pandemic. It has a high degree of prefabrication where individual modules serve as complete spaces in buildings. These modules are manufactured in controlled environments and transported to construction sites for fast assembly. Considering the nature of a pandemic, the prevention of cross infection between occupants should be carefully considered in the floor layout design of medical and quarantine facilities. Ventilation systems are required to supply clean air to patients and health care staff and to create negative air pressure in the wards to further reduce the probability of disease transmission. This paper provides a focused review of modular medical and quarantine facilities, which cover the structural forms, floor layout design, and equipment arrangements. Further construction management technologies are highlighted for the modular prefabrication and construction of medical and quarantine facilities.

Connections play a vital role in the transfer of lateral forces and energy dissipation in cross-laminated timber (CLT) structural systems. However, moisture exposure (e.g., rain during or after construction) can affect the durability of CLT structural members and their connections due to the hygroscopic nature of wood. Limited knowledge exists on the moisture performance of CLT connections. Therefore, in this study, a CLT shear wall-to-diaphragm angle bracket connection was exposed to simulated rain and relative humidity cycling (wetting) and subsequent redrying followed by mechanical loading cyclic testing. Four wood species (Douglas-fir, southern pine, Norway spruce, and spruce-pine-fir) and three wetting durations were applied to understand the effect of moisture intrusion on the connection performance, which was evaluated in terms of strength, stiffness, and energy dissipation. Two force–displacement backbone models were fitted to the experimental data. The results suggest a statistically significant increase (9%–15% for different species) in the peak strength and no change in the stiffness and energy dissipation capacity after the wetting and redrying cycles. However, additional studies should be conducted to gain further insight into the observed increase in load-carrying capacity. Additionally, the authors caution against considering any strength increase until further studies are conducted.

Abstract

Renovations and facility system upgrades are necessary investments to extend the useful life of a facility, reduce maintenance, and improve the efficiency of installed systems. It is important to carefully consider the factors that affect these decisions in dormitories, because they negatively impact residents in the short term; however, they improve occupant satisfaction and comfort in the long term. This study employed a Delphi method with a panel of experts to identify and rank order the factors for renovation and system upgrade decisions and the sources of information for these decisions. This study determined, with moderate consensus, that the three most important factors were: (1) facility condition, (2) health and safety, and (3) the dormitory’s suitability for the owner’s objectives or mission. The most important sources of information were input from maintenance technicians, maintenance work order databases, and condition assessments. This study could contribute to renovation and system upgrade decisions by identifying a method to reach a consensus on a rank order of the factors for use in multicriteria decision-making (MCDM). In addition, this study could contribute to the practice of prioritizing information-gathering efforts to support renovation decisions.

Practical Applications

To help facility maintenance managers (FMMs) make decisions about the scope and timing of renovations or upgrades to the facility systems in their dormitories, this study used an expert panel to agree on the order of importance of 15 potential decision factors. The panel was made up of experienced maintenance managers or directors from universities in the United States and US military. The FMMs determined that the three most important factors that impacted their renovation and upgrade decisions were: (1) facility condition, (2) health and safety of the occupants, and (3) how well the dormitory met the organization’s objectives. In addition, the experts answered that the three most important data sources they used when deciding included maintenance technicians’ inputs, work order databases, and facility condition assessments. FMMs should focus their time and efforts on the three factors and invest in the information sources determined when making decisions about the scope and timing of dormitory renovations and system upgrades.

With the continuous progress of urbanization and the rapid development of building facade floodlighting, problems such as excessive lighting, serious light pollution, and high energy consumption are becoming increasingly prominent. In this paper, three methods comprising field measurement, questionnaire survey, and energy-efficiency simulation were integrated to develop the floodlighting luminance control curve of a building facade at night and also to carry out an energy-efficiency analysis. Through the field measurement of the floodlighting of the building facade, combined with the method of scene simulation, several virtual combined scene pictures with different sky luminance and different floodlighting luminance of the building facade were made. Furthermore, the optimal floodlighting luminance range as the sky luminance varies was obtained in the form of a questionnaire when the virtual scene pictures were presented on a computer. Then, the floodlighting luminance control curve with the decrease of the sky luminance was developed to achieve the purpose of reducing energy consumption. Finally, energy efficiency analysis of the lighting control curve was undertaken. The result revealed that when the sky background luminance is 8.98–0.51 cd/m², the recommended floodlighting luminance range of the building facade is 6.13–4.44 cd/m². What is particularly interesting is that the energy-saving effect is remarkable, and the energy-saving rate at each time is greater than 15%.

Although the use of building information modeling (BIM) and automatic clash detection has improved the construction coordination process in construction projects, the industry still suffers from on-site fixes of issues, which can cause construction delays and cost over-runs. Several research studies have investigated the causes of constructability issues or rework but have not focused on how the issues are missed at the construction coordination stage, which is a mitigation strategy that can minimize field detected issues. This research, via expert interviews and utilizing the grounded theory approach, determined the underlying causes of not capturing field-detected issues during the BIM-based construction coordination process. Missing model elements, not considering operability or maintainability, and inaccurate as-built model updates were the most common causes. The research findings can benefit industry practitioners by providing the causes and preventive measures that can enhance the ability to capture issues before they occur in the field. Moreover, this research also provides future researchers with the critical causes that need to be tackled to improve BIM-based construction coordination.

The objective of this research study is to formulate and develop an automated multiobjective optimization model for modular construction projects. The model is designed to support planners of modular construction in generating optimal floor plan designs that minimize the total cost of modular construction projects while maximizing their floor plan functional performance. A case study of a modular construction project was analyzed to highlight the use of the model and demonstrate its capabilities. The results of the case study analysis illustrate the original contributions of the model in automating the generation of optimal trade-offs between the two aforementioned important objectives of modular construction projects by optimizing the holistic impact of floor plan modularization, module finishing level, and module transportation planning decisions. The results also confirm the novel capabilities of the model in identifying for each prefabricated module an optimal (1) width and length; (2) finishing level; and (3) truck assignment, delivery day, and location and orientation on the assigned truck.

Abstract

A novel architectural typology of buildings is proposed with special transmission of each window without the use of additional daylight shading/redirecting devices. Minimum transmission at a preset time and self-regulated transmission at the rest of the time, adapted to the sun’s trajectory, are achieved due an optical filter having two thin-film gratings with alternating transmissive and chromogenic strips. The building typology algorithm was realized by calculating the geometric parameters of grating filters for various facades and their temporal characteristics of direct light transmittance. The results demonstrated the minimization of transmission at the preset time of day, and acceptable filter operation at other times, as also validated by daylighting and glare metrics evaluation. A smart window with grating filter can partially or completely block direct sunlight and let in diffused light, unlike other versions of smart technologies that have been developing rapidly in recent years. The ergonomic, environmental, and aesthetic properties of such a smart window are improved by the absence of additional devices. This typology has potential applications, especially in office and industrial buildings due to the need for sun protection during the daytime, as well as in buildings with curved facades with continuous azimuth changes.

Practical Applications

The proposed architectural typology of buildings with special characteristics of direct light and solar transmission of each window due to the use of the novel grating optical filter, the theoretical basis for its implementation and the results obtained indicate potential prospects for application in office and industrial buildings with the demand for sun protection, especially for buildings with curved facades. This approach provides an optimized light transmission capacity of each window without the use of additional daylight shading/redirecting devices and improves the ergonomic, environmental and aesthetic properties of the window and the room. For the practical use of the proposed typology of buildings, in future work it is planned to study in detail the annual performance of the window filter, evaluate the economic aspects and create a computer program convenient for architects that allows calculating all the necessary individual parameters of all windows of the building.

This paper presents an automated as-is façade modeling method for existing and historic high-rise buildings, named Scan4Façade. To begin with, a camera drone with a spiral path is employed to capture building exterior images, and photogrammetry is used to conduct three-dimensional (3D) reconstruction and create mesh models for the scanned building façades. High-resolution façade orthoimages are then generated from mesh models and pixelwise segmented by an artificial intelligence (AI) model named U-net. A combined data augmentation strategy, including random flipping, rotation, resizing, perspective transformation, and color adjustment, is proposed for model training with a limited number of labels. As a result, the U-net achieves an average pixel accuracy of 0.9696 and a mean intersection over union of 0.9063 in testing. Then, the developed twoStagesClustering algorithm, with a two-round shape clustering and a two-round coordinates clustering, is used to precisely extract façade elements’ dimensions and coordinates from façade orthoimages and pixelwise label. In testing with the Michigan Central Station (office tower), a historic high-rise building, the developed algorithm achieves an accuracy of 99.77% in window extraction. In addition, the extracted façade geometric information and element types are transformed into AutoCAD command and script files to create CAD drawings without manual interaction. Experimental results also show that the proposed Scan4Façade method can provide clear and accurate information to assist BIM feature creation in Revit. Future research recommendations are also stated in this paper.

The post-earthquake seismic assessment of buildings is usually performed through numerical methods. Geometrical simplifications of the structure are often introduced. Moreover, the seismic input is evaluated following the indications of reference standards, although overestimated forces may be obtained compared with those that actually occurred. In this paper, through the case study of a single-nave church, the significant influence of the geometric modeling of the roof on the structural response and the importance of the correct definition of the seismic input in post-earthquake analyses are shown, even in the case of very simple structural organisms. A preliminary limit analysis and nonlinear static analyses, after the definition of new response spectra based on a subset of the recorded ground accelerations, have been performed. The decisive role played by the correct geometric modeling and the proposed response spectra in the simulation of the overall response and damage status is shown. Finally, the importance of the method in the design of retrofitting works is highlighted through the basic example of the numerical response of the structure reinforced with CFRP composite.

Abstract

China’s Hot Summer and Cold Winter zone, with a 550 million population, accounts for 45% of China’s building energy consumption; as such, building retrofits could offer substantial energy savings. This paper presents results from a dynamic thermal modeling study of a typical urban multistory residential building under three types of air conditioning (A/C) operating schedules. Seven energy-saving retrofit measures (external wall insulation, roof insulation, double-glazing, air infiltration control, window shading, communal staircase design, and energy-efficient A/C) were evaluated, and the retrofit strategy with the highest annual energy savings and lowest thermal discomfort was identified. This retrofit strategy was subsequently evaluated for other flats (apartments) with different orientations and positions in the typical building. The annual space-conditioning energy could be reduced by 59%–68%, depending on the flat location, orientation and A/C operating schedule. The findings were then scaled up to estimate the potential energy savings in the city of Chongqing. More than 320 multistory residential buildings were represented by 12 archetypes. Space-conditioning energy consumption was reduced by up to 58% (18.8 TWh). This work provides evidence of the potential energy savings of city-scale retrofit that could aid China in reducing building energy consumption and achieving net-zero carbon emissions by 2050.

Practical Applications

It was possible to explore a wide range of refurbishment options for China’s highly energy-consuming Hot Summer and Cold Winter zone with hot, humid summers and mild, chilly winters using dynamic thermal models. The simulation models developed in this paper revealed that double-glazing with air infiltration control is the most effective retrofit measure for middle-floor flats, but for top-floor flats, roof insulation is the most effective; south-facing flats consume more high energy consumption than north-facing flats. Furthermore, high-rise buildings consume less energy than low-rise buildings per square meter, and one-bedroom flats consume more energy than three-bedroom flats per square meter. This study also demonstrated the procedure to develop thermal comfort evaluation methods, A/C operating schedules, and construction parameters from literature in this climate zone when there were no standards or databases available. Findings offer a tangible, clear retrofit strategy that considers different A/C operating schedules, flat locations, and building archetypes. It can assist decision-making by practitioners and homeowners aiming to upgrade the building stock of this climate zone which covers 3.4 billion m² with a 550 million population to reduce energy consumption and improve occupant comfort.

Precast reinforced concrete technology has been widely applied in Italy for industrial facilities throughout the years and nowadays older buildings show structure and energy-related deficiencies. In order to promote integrated redevelopment interventions, the research sets a methodological framework to investigate such a vast building stock and proposes a classification of the different typological variants registered according to structural, architectural, and technological aspects. This paper focuses on the industrial building stock realized recurring to prefabrication techniques in the geographical cluster of Casentino, in Tuscany. The research involved 675 buildings intended for production activities whose specifications were collected in a GIS database as alphanumerical parameters. Data, obtained through digital surveys, aerial views, and on-field recognitions, were postprocessed to provide a general overview of the most recurring characteristics and highlight evolutionary trends over years. Seven typological declinations were identified for prefabricated reinforced concrete industrial buildings and their diffusion was related to the different periods of constructions. Roofing systems, structural solutions, and external wall components were chosen as key parameters for the classification procedures. The definition of recurrent typological solutions in industrial buildings is meant as a preparatory operation that will facilitate the assessment of their current architectural, technological, structural, and specifically energy and environmental performances. This research paves the way toward the development of protocols and guidelines containing integrated retrofitting strategies and solutions tailored on the specific issues of each variant.

The initial curriculum of Drexel University’s Architectural Engineering program evolved considerably during the first five years—academic years 1986–1987 to 1991–1992—leading up to its initial accreditation by ABET in 1992. Taking advice from an industry advisory council and students, the goals were narrowed from producing broad building generalists to specialized engineers with an understanding of architecture and other architectural, engineering, and construction industry disciplines. These changes resulted in a marked reduction in the number of architecture courses, giving students more flexibility in choosing courses, both within engineering and the broader university. This paper focuses on the initiation and evolution of the architectural engineering program during the first five years, leading up to its initial accreditation. A sketch of the program’s evolution since 1992 is provided to demonstrate changes that may be expected to occur after initial accreditation.

This paper presents a streamlined image-based modeling-to-simulation framework to better assess the hazard vulnerability of masonry structures. In this framework, a masonry wall image is used as an input for 3D discrete element modeling and analysis. Therefore, individual bricks are directly detected from the image and the interactions of the bricks are explicitly considered in the numerical simulation of the masonry wall. The bricks in the masonry wall image are segmented first, from which the geometric information of the bricks is obtained using a bespoke algorithm. Segmented bricks are then approximated into n-sided polygons using the splitting and Douglas–Peucker methods to develop simplified brick geometries. This shape simplification is performed to lower the computational cost for the discrete element analysis while reasonably approximating the overall brick geometry and maintaining the simulation fidelity. The simplified polygons are exported to a free and open-source physics engine as scalable vector graphics, from which a 3D masonry model is developed, and rigid body discrete element simulation is performed using the impulse-based dynamics. This paper demonstrates the image-based modeling-to-simulation framework can estimate collapse scenarios from an input masonry wall image and proposes a prototype that transforms visual images into critical domain knowledge that would be useful for disaster preparedness. With enhanced predictive capabilities, this framework can contribute to innovations in the hazard vulnerability assessment of masonry structures.