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Radon (Rn 222) is a significant contributor to natural radiation exposure in residential environments such as single-family houses and multistory buildings. This study monitored radon activity concentration (RAC) in 455 apartments in 30 multistory buildings in Buzău, Romania. Integrated measurements of the RAC using CR-39 nuclear track detectors were conducted for a period of 3 to 4 months. The results revealed that the RAC varies between buildings, with an annual average between 33 and 77 Bq/m3. This variation may be attributed to poor ventilation and the chimney effect in common ventilation ducts, which may facilitate radon displacement vertically. Also, apartments with low occupancy or inadequate ventilation showed higher radon levels of up to 285 Bq/m3. The study highlights the potential risk of increased radon exposure in energy-efficient buildings due to poor ventilation, emphasizing the need for special attention to radon mitigation measures in building design. The results emphasize that the RAC is influenced by building characteristics, room use, and ventilation, with significant implications for health risks in urban residential environments.

Multi-story buildings in seismic regions are susceptible to earthquake-induced damage; however, the direct correlation between observed damage patterns and underlying failure mechanisms remains insufficiently understood. The Ms6.8 Luding earthquake, which struck Luding County, Sichuan Province, China, in September 2022, offers a unique opportunity to investigate this relationship, as it affected a concentrated area with diverse building types and preserved a wide range of damage states. This study leverages the distinctive conditions of the Luding earthquake to elucidate the influence of wall element distribution on structural failure modes under seismic loading. To elucidate the underlying mechanisms, three representative buildings were analyzed using a one-dimensional numerical model. The simulations yielded shear force distributions, shear ratios, and displacement ratios across structural components, enabling a detailed assessment of failure modes. The results indicate that torsion-dominated structures are susceptible to premature failure of low-stiffness components due to excessive displacement, whereas high-stiffness components generally remain intact owing to their ductility. In contrast, translation-dominated structures fail when high-stiffness components fracture at small displacements, resulting in global collapse without substantial ductility or load-bearing contribution from other elements. Structures that remained undamaged exhibited a relatively uniform stiffness distribution, enabling them to resist seismic forces primarily through overall capacity rather than ductility. The numerical results closely reproduced the observed damage patterns, thus validating the proposed mechanisms for the three structural categories. These findings contribute to a deeper understanding of seismic damage processes and provide a basis for enhancing seismic design and retrofitting strategies for both new and existing structures.

The structural behavior prediction of the multistory reinforced concrete (RC) buildings with masonry infill walls (MIWs) during earthquakes is challenging. This paper presents a nonlinear macromodeling strategy seeking a simple, reliable, and low-cost computational analysis of the multistory RC buildings that comprise MIWs, and that use frames or shear walls (SWs) for resisting the lateral load. The strategy employed four plastic hinge (PH) models for tracking the deformations (flexural, shear, and torsion) of the frame elements and joints, a multilinear plastic link for modeling the MIW, and a nonlinear multilayer shell element for modeling the SW. A flexural PH model characterized by discretization into fibers, a recommended position, and an iterative estimating for the PH length using a distinct formula for each loading level was proposed. This strategy was validated through eleven macromodels investigating four bare frames, four MIWs frames, and a SW where the average ultimate lateral load error was 9.2%, 3.6%, and 0.4%, respectively. Finally, the structural behavior of real ten-story buildings with/without MIWs was investigated. The results showed that the MIWs increased the shear capacity and the lateral stiffness with an average of 44.3% and 118.6%, respectively. Also, both the frames buildings with MIWs and the bare SWs buildings showed approximately equal lateral load capacities. Local damages in the RC vertical elements and yielding of the MIWs were recorded simultaneously. However, the MIWs yielding (and also failure) occurred earlier for the frames buildings compared with the SWs buildings in which the stress was relaxed in their MIWs.

A decision support process is presented to accommodate selecting and scaling of earthquake motions as required for the time domain analysis of structures. Code-compatible suites of seismic motions are provided being, at the same time, prequalified through a multi-criterion approach to induce response parameters with reduced variability. The latter is imperative to increase the reliability of the average response values, normally required for the code-prescribed design verification of structures. Structural attributes like the dynamic characteristics as well as criteria related to variability of seismic motions and their compliance with a target spectrum are quantified through a newly introduced index, δsv–sc, which aims to prioritize motions suites for response history analysis. To demonstrate the applicability of the procedure presented, the structural model of a multi-story building was subjected to numerous suites of motions that were highly ranked according to both the proposed approach (δsv–sc) and the conventional one (δconv), that is commonly used for earthquake records selection and scaling. The findings from numerous linear response history analyses reveal the superiority of the proposed multi-criterion approach, as it extensively reduces the intra-suite structural response variability and consequently, increases the reliability of the design values. The relation between the target reliability in assessing structural response and the size of the suite of motions selected was also investigated, further demonstrating the efficiency of the proposed selection procedure to achieve higher response reliability levels with smaller samples of ground motion.

The fire safety and protection of a multistory building seems not only national, but a worldwide concern. To sort out this issue, there is a special need to pay attention towards fire safety management system of buildings. In recent decades no. of fire incidents to whole over the world increased to a very high level and yearly a large number of users died and a substantial property damage takes place. In this regard, effective fire safety management system plays an important role towards the fire safety of building and to avoid fire incidents and reduce its effects. The major aim of this article is to evaluate the existing fire safety measures by designing a fire safety audit, for a public sector multistory building, in which all the components of fire safety system will be inspected by considering relevant NFPA standards and UAE fire and life safety codes. By conducting fire safety audit, conclusions are derived and safety gaps are identified in existing fire safety management system, which may be rectified for effective fire safety controls. Accordingly, recommendations drawn on the basis of findings, analysis and conclusions for proper fire safety management system.

The presence of soils, subjected to consolidation, increases the risk of the additional sediment formation, which may affect the object stability in the base.

The article presents the main provisions of modeling multi-story buildings with seismic isolation, the characteristics of the seismic isolation device, structural elements and materials, the methodology for conducting experimental studies on a laboratory vibro-stand under dynamic (seismic) effects and the results of the modeling.

Greenhouse cultivation has evolved from simple covered rows of open-fields crops to highly sophisticated controlled environment agriculture (CEA) facilities that projected the image of plant factories for urban agriculture. The advances and improvements in CEA have promoted the scientific solutions for the efficient production of plants in populated cities and multi-story buildings. Successful deployment of CEA for urban agriculture requires many components and subsystems, as well as the understanding of the external influencing factors that should be systematically considered and integrated. This review is an attempt to highlight some of the most recent advances in greenhouse technology and CEA in order to raise the awareness for technology transfer and adaptation, which is necessary for a successful transition to urban agriculture. This study reviewed several aspects of a high-tech CEA system including improvements in the frame and covering materials, environment perception and data sharing, and advanced microclimate control and energy optimization models. This research highlighted urban agriculture and its derivatives, including vertical farming, rooftop greenhouses and plant factories which are the extensions of CEA and have emerged as a response to the growing population, environmental degradation, and urbanization that are threatening food security. Finally, several opportunities and challenges have been identified in implementing the integrated CEA and vertical farming for urban agriculture.

Throughout the last two decades the timber building sector has experienced a steady growth in multi-storey construction. Although there has been a growing number of research focused on trends, benefits, and disadvantages in timber construction from various technical perspectives, so far there is no extensive literature on the trajectory of emerging architectural typologies. This paper presents an examination of architectural variety and spatial possibilities in current serial and modular multi-storey timber construction. It aims to draw a parallel between architectural characteristics and their relation to structural systems in timber. The research draws from a collection of 350 contemporary multi-storey timber building projects between 2000 and 2021. It consists of 300 built projects, 12 projects currently in construction, and 38 design proposals. The survey consists of quantitative and qualitative project data, as well as classification of the structural system, material, program, massing, and spatial organization of the projects. It then compares the different structural and design aspects to achieve a comprehensive overview of possibilities in timber construction. The outcome is an identification of the range of morphologies and a better understanding of the design space in current serial and modular multi-storey mass timber construction.

Throughout history, earthquakes have posed a substantial risk, leading to extensive devastation and tragic loss of human lives. Repeated earthquake activity can be particularly concerning as it can lead to further damage and destruction. Hence, implementing approaches aim at enhancing a building’s resilience to seismic activity and mitigating the detrimental effects of earthquakes. Be it a single event or repeat events, it holds significant importance. This study aims to conduct a dynamic analysis to assess the performance of a multi-storey building subjected to seven seismic loads, including single and repeat occurrences of near-field earthquakes. The characteristics of the seismic loads: i) the distance from the epicenter is less than 15km, (ii) the magnitude is equal to or greater than 5.5 and (iii) the peak ground acceleration (PGA) is equal to or greater than 0.15g. An investigation into the displacement of the building caused by single and repeated seismic events was conducted to evaluate the structural integrity of the building. Measurements of the resulting displacement at the X-axis in a single event equal to those in repeated events indicate that it was recorded in the Y direction 249.56 mm in the X direction, and then this displacement decreased to 40.64 mm in the Y direction. However, this displacement at the Y-axis was recorded as 101.07 mm in the X direction and then increased to 227.17 mm in the Y direction. This indicates that the direction of single and repeated seismic loads can affect the amount of displacement in the X-axis and Y-axis of the structure. The displacement caused by the seismic load is directly proportional to the intensity of the load and the rigidity of the structure.