•Air temperatures in the thermal driven ventilated turbine hall were measured on-sites.•3D-CFD model could disclose the key characteristics of turbine hall thermal fields.•Simulation results of ...buoyancy driven hall flows were in agreement with analytical ones.•Working zone air environment could be effectively cooled by the floor supplying air jets.•Optimized supplying vents configurations were identified by parametric investigations.
The turbine hall houses a number of components with intense heat release, resulting in a hot and humid air environment and making it very unpleasant for plant staffs to conduct maintenance work there, particularly at a hot outdoor environment. The traditional pure buoyancy driven natural ventilated could fulfil the overall heat exhausting requirement, however, creating hot environment at several positions due to the vortex airflow structure. As only part of the building need to be cooled, a localized cooling system with assisting mechanical fans is used. Buoyancy driven natural ventilated flows primarily occupying this turbine hall have been investigated by a computational fluid dynamics (CFD) model and an on-site measurement. The ventilation airflow is solved by 3D steady state Reynolds Averaged Navier-Stokes (RANS) equations in conjunction with the SST k-ω turbulence model. The numerical codes and procedures were validated by comparing with on-site measurements. The concept of mean age of air is used to evaluate the natural ventilated efficacy. Following that, the potential of using mechanical vents and slabs to cool equipment work area at this buoyancy driven natural ventilated hall is analysed. The simulation results show that the mechanical vents could decrease air temperature and increase air exchange efficiency at work area effectively on condition that the local airflow pattern is well organized, which is strongly related to the ejection direction and velocity. Present research could benefit future development of the ventilation design in the power plant buildings.
•Snow loads may cause catastrophic damages at prefabricated industrial buildings.•Brittle damages may occur at the thinned ends of the purlin.•Different prefabricated RC purlin tests have been ...conducted.•The proposed Z type reinforcement enhanced shear capacity of the purlin.•The results were compared with TS-9967 standards and field tests.•The numerical analysis was performed using ABAQUS to determine optimum Z type reinforcement.
In prefabricated industrial buildings, damages and collapses may occur under snow loads. If the necessary precautions are not taken, the damage can spread to the whole structure which leads to total collapse. Therefore, it is very crucial for manufacturers to comprehend the nature of the damage and to take necessary precautions to prevent this damage. In this present study, the damages occurred at dapped-end region of prefabricated purlins due to snow load accumulated at the roof and the reasons for these damages were investigated in detail. Pursuant to this goal, comprehensive experimental and numerical studies have been undertaken. 10 specimens with 5 different configurations were tested under four point loading. A novel reinforcement detail and the usage of practical methods used by the manufacturers are selected as main parameters. In all purlins, damages occurred at the dapped-end in shear formation. The experimentally obtained results were compared with field tests and TS9967 design code. It was observed that the specimen with “Z” type of the proposed novel reinforcement exhibited approximately 30% higher load capacity than that of other specimens. Moreover, the numerical analyses were performed in order to determine optimum “Z” type reinforcement for dapped-end purlin beams using finite element methods.
Abstract The masonry structure is one of the main types of modern industrial buildings in China because of its local materials and simple economy. However, these buildings often suffer damage and ...cracks due to uneven settlement of the foundation and disrepair, which affects the safe and normal use of the structure. It is urgent to maintain and strengthen the structure to restore the safety of the structure. This paper takes Baoji Shenxin Yarn Factory - Kiln Factory as the actual engineering background, and use the finite element software ABAQUS based on Winkler’s theory to establish a finite element calculation model that can more conveniently respond to the effects of different foundation settlements. Through the simulation analysis, the influence law of the local settlement of the kiln foundation on the overall structural force state was obtained, which can provide an important reference basis for the maintenance and reinforcement of the structure.
Abstract
The relevance of the work is due to the increasing possibility of impact on the critical building structures of industrial buildings of short-term dynamic loads in abnormal emergencies. ...These situations lead to significant damage of the constructions of buildings. There is a high possibility of human victims and significant damage of expensive technological equipment when the structures collapse. Therefore, in order to ensure further functioning of the structure, it is necessary to design building structures as well as the object on the whole with the properties of survivability under non-stationary impact. Such properties should be analyzed when constructing scenarios of origination and development of emergency situations as well as analyzing risks. In the course of the research the strain gauge methods were used to measure deflections, accelerations and loads on the samples. The work proposes a method for assessing the degree of survivability of a critical building structure under short-term dynamic loading based on the analysis of the energy parameter. Using the example of a specific test of a bending reinforced concrete element for short-term dynamic load the values of the specified coefficient were obtained.
In the past few years, the private sectors and industries have focused their attention on sustainable development goals to achieve the better and more sustainable future for all. To accomplish a ...sustainable community, one requires to better recognize the fundamental indicators and selects the most suitable sustainable policies in diverse regions of the community. Considering the huge impact of construction industry on sustainable development, very less research efforts have been made to obtain worldwide sustainable elucidations for this type of industry. As a large sector of construction industry, industrial buildings consume enormous amounts of energy and financial assets, and play a key character in job creation and life quality improvement in the community. In order to assess the sustainable industrial buildings by means of multiple indicators, the present study introduces a hybrid multi-criteria decision-making methodology which integrates the fairly aggregation operator, the MEthod based on the Removal Effects of Criteria (MEREC), the stepwise weight assessment ratio analysis (SWARA) and the additive ratio assessment (ARAS) methods with intuitionistic fuzzy set (IFS). In this respect, firstly new intuitionistic fuzzy weighted fairly aggregation operators are proposed and then employed to aggregate the decision information in the proposed hybrid method. This operator overcomes the limitations of basic intuitionistic fuzzy aggregation operators. To find the criteria weights, an integrated model is presented based on the MEREC for objective weights and the SWARA for subjective weights of indicators under IFS context. To rank the sustainable industrial buildings, an integrated ARAS method is employed from uncertain perspective. Further, a case study concerning sustainable industrial buildings evaluation is presented to illustrate the superiority and practicality of the developed methodology. The advantages of the developed approach are highlighted in terms of stability and reliability by comparison with some of the existing methods.
•Addresses literature gap of low-energy factories in warm-climate emerging nations.•Confirms efficacy of active & passive measures in application to industrial buildings.•Embodied energy (71%) ...significantly exceeds operation energy (17%).•Energy reduction from rooftop PV & recycling exceeds life cycle energy demand.
A life cycle assessment (LCA) is conducted on a low-energy industrial building under construction in Thailand. The building has a gross floor area of 14,938 m2 and a 20-year lifetime. As energy-saving initiatives need to expand beyond the established domain of low-energy residential and commercial buildings, this study demonstrates the successful application of active and passive energy-saving measures to a large, energy-efficient industrial building—the first to be surveyed by an LCA. LED lighting, minimal air conditioning, and passive ventilation architecture reduce operation phase burdens. As a result, the manufacturing phase yields largest impacts in primary energy demand (71%), global warming potential (60%), and four other environmental impact categories. This is largely attributable to steel and concrete production and a higher embodied energy quantity per material. Additionally, four scenarios—a base case, recycling case, photovoltaic system scenario, and combined recycling/photovoltaic scenario—are simulated to evaluate strategies for further energy reduction. Analysis indicates that significant life cycle energy savings can be achieved through recycling (29%) and a rooftop PV system (64%). The combination of both enhancements compensates for all manufactured material embodied energies and results in a building with zero or sub-zero total life cycle energy demand. Buildings that are already low-energy can further reduce environmental impacts through inclusion of the aforementioned approaches in design and implementation.
•We present failure modes observed in RC precast structures during field reports after the 2012 Emilia Earthquake.•We identify and discuss the most frequent causes of collapse.•We present previously ...undocumented collapses.
The present paper presents a complete and commented collection of cases of damage and collapse in reinforced concrete (RC) precast industrial buildings, observed by the authors during a series of field surveys after the 2012 Emilia earthquake in Northern Italy. They were selected among a total of about 2000 industrial RC precast buildings, whose structural characteristics and damage have been collected in a large database by the authors.
The main causes of the collapses were vulnerabilities related to the structural characteristics of Italian precast buildings not designed with seismic criteria. In particular, these structures were typically built as an assembly of monolithic elements (roof elements, main and secondary beams, columns) in statically determinate configurations. The most common failure causes identified were: the absence of mechanical connectors between precast monolithic elements, the interaction of structural elements with non-structural walls, the insufficient column bending capacity, the rotation of pocket foundations, the inadequacy of connections of external precast cladding walls to bearing elements (columns and beams), the overturning of racks in buildings used as warehouses or in automated storage facilities.
The present paper shows the results of a literature survey aimed at exploring how the indoor environment in buildings affects human comfort. The survey was made to gather data that can be useful when ...new concepts of controlling the indoor environment are developed. The following indoor environmental conditions influencing comfort in the built environment were surveyed: thermal, visual and acoustic, as well as air quality. The literature was surveyed to determine which of these conditions were ranked by building users as being the most important determinants of comfort. The survey also examined the extent to which other factors unrelated to the indoor environment, such as individual characteristics of building occupants, building-related factors and outdoor climate including seasonal changes, influence whether the indoor environment is evaluated as comfortable or not. The results suggest that when developing systems for controlling the indoor environment, the type of building and outdoor climate, including season, should be taken into account. Providing occupants with the possibility to control the indoor environment improves thermal and visual comfort as well as satisfaction with the air quality. Thermal comfort is ranked by building occupants to be of greater importance compared with visual and acoustic comfort and good air quality. It also seems to influence to a higher degree the overall satisfaction with indoor environmental quality compared with the impact of other indoor environmental conditions.
Since the old industrial buildings bear many functions of industrial production and storage in the service stage, the dust generated by the regeneration construction is often accompanied by ...industrial pollutants, causing irreversible damage to the personal safety of construction workers. However, little consideration has been given to the uncertainty of dust emissions and the dynamics of construction personnel movement. Therefore, reducing the risk of dust hazards during the regeneration of old industrial buildings is imperative. This study draws on the trace intersecting theory to analyse the cause of the hazard risk associated with reconstruction dust and explore the impact of the spatiotemporal distribution characteristics of reconstruction dust and its coupling effect with construction on-site personnel activity trajectories and uses the risk matrix method to assess the dust hazard risk in the reconstruction of old industrial buildings. Finally, the renovation and reinforcement process of the first floor of a printing building in Xi’an was considered as an example for verification. The results indicate that the risk assessment model results were highly consistent with the actual situation and risk value for the entire area was 6.05, indicating a risk level of IV. Immediate measures should be implemented to reduce dust concentrations or the frequency of construction personnel activity, thereby minimising potential harm.
Ventilation is essential for the health and safety of workers in industrial buildings, as it can reduce the exposure to hazardous substances. This study used an experimental chamber with strong ...thermal buoyancy to measure the air velocity and pollutant concentration under two types of exhaust hoods: reinforced and traditional. The data-driven turbulence model with a new wall function was validated by comparing the simulated results with the measured data. Next, different ventilation strategies were evaluated in a small room. The reinforced exhaust ventilation had the best performance, but it also created vortices due to the impinging flow, which trapped pollutants. To solve this problem, an improved reinforced exhaust hood with multiple independent inlets was designed. Through adjustment of the velocities of these inlets, the vortices caused by wall impingement flow were minimized, resulting in a 77% decrease in pollutant concentration. For a large room, the study optimized the jet collision velocity when multiple reinforced exhaust hoods operated together. The reinforced exhaust ventilation system reduced the pollutant concentration in the breathing zone to 89% of the concentration under existing ventilation. Moreover, the improved reinforced exhaust hood provided a significant energy saving. In small and large industrial buildings, the hood reduced fan energy consumption by more than 80% and air conditioning energy consumption by more than 60%.
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