Typical Floor Research Articles

An approach to energy efficient lighting design for economic residential flats

The lighting design in a residential building now-a-days is not only limited to general lighting but also it is focused to provide quality lighting with the help of wide range of available luminaire with different orientations as well as colours with efficient use of energy, that opens up accurate characteristics of specific areas in any room of the building. The affordable housings in many states are some of the examples of residential building where most of the flats in a typical floor are using conventional lighting systems which are not energy efficient and light level is low compared to standards. This paper is mainly focused to provide a budget friendly as well as energy efficient lighting design with the help of new and energy efficient lamps using DIALux Software, which can be proposed to renovate the existing conventional lighting systems. In this paper effort has been made to reduce the power consumption in all rooms and lux levels has been achieved as per standard values along with good amount of energy saving with the use of newer technologies.

Data-driven occupant-centric rules of automated shade adjustments: Luxembourg case study

This study presents key findings of observed datasets in a nearly zero-energy office building for over 66 working days from June to mid-September in 2019, Luxembourg. Measurements of indoor and outdoor environmental parameters as well as user-shade override adjustments were extracted from the KNX-based building management system (BMS) in 47 office rooms located in three typical floor levels. Relative frequency and “rate of change” of blind use were analysed in terms of window orientation, occupancy level, and the time of the day. Logistic regression and data mining techniques were used to identify potentially useful and understandable occupant behaviour patterns and reveal the main triggers behind blind adjustments. The well-designed automation system together with the inner glare protection formed the base of very low user-shade interactions. A mean of 0.184 manual blind adjustments per day per office. Eight regression sub-models were developed and all were incapable of predicting user-shade lowering and raising events. Alternatively, two user profiles were mined based on 20 rules gained from clustering analysis: user (ß) was representing the passive user, and user (μ) the medium user. Overall, we conclude that the automated shading system in this building is satisfactory, user-friendly, and a robust control system.

Study on Fire Resistance of Floor Structures in High-speed Train

According to the standard EN 45545, fire resistant tests of floor structures in high-speed train were carried out. Two typical floor structures which were placed in the passenger train were tested. Integrity and insulation are main performance criteria to evaluate fire resistance of floor structures. The furnace temperature is in accordance with the requirements in the standard ISO 834. The surface temperature and deflection were recorded with time. Glass wool and aluminium corrugated sandwich structure in two structures were burned through. The experiments were terminated at 30 minutes and 31 minutes respectively for the two structures. A large amount of smoke and the sound of cracking of the exposed surface of the test piece were produced, although the unexposed surface of test pieces did not reach the failure condition.

Defining work-zones for resource allocation in Hong Kong public housing project construction using heuristic rules and operations simulation

In Hong Kong, 6-day construction cycle always being used for constructing one typical floor of concrete building superstructure in a week. Work-zones are defined in the working platform for better allocation of limited resources. Once the work-zones are defined, the resources (labour, plant, materials) will be allocated to a specific zone to deliver the works on a particular day of the 6-day construction cycle. In practice, the definition of work-zone is dependent on the experience of project manager. Yet, there is no past research studied the evaluation of work-zone definition schemes. As such, in this research study, three heuristic rules are proposed for choosing better scheme of work-zone. The heuristic rules are based on (i) lengths of work-zone dividing line, (ii) fluctuations of daily duration, and (iii) utilisation rates of resource. To illustrate the steps of evaluating the scheme, an illustrative example is given. To illustrate the method application of the rules, a practical case study of constructing a 40-storey housing is given. The proposed rules were verified based on sensitivity analysis and expert validation. Conclusions are drawn by expressing the contributions and limitations of the proposed rules, followed by suggesting future research works.

Post-pandemic residential environment in Amman

PurposeThe fundamental lifestyle changes, economic concerns, property price increase and construction cost can explain the transformation of traditional housing layouts to massive indoor planes by prioritizing indoor over outdoor spaces. That is, overlooking the effect of outdoor spaces, on life quality, to compensate for indoor spaces expansion. As a result, this study highlighted outdoor spaces and their impact on psychological wellbeing, especially through the enforcement of quarantine conditions and social distance.Design/methodology/approachTo achieve that, a spatial analysis for (70) apartments, in Amman, was undertaken to understand outdoor space in terms of spatial configuration, size, adjacent spaces and usage. An assessment for outdoor space based on both users' and professionals' perspectives to discuss the current situation condition in terms of physical layout, activities, area, spaces' treatment and associated incentives. (125) responses were collected from the head of household living in an apartment through using a structured questionnaire. In addition, feedback in terms of dynamics home components, home buyers' market trends and local regulations were collected from (22) professionals.FindingsStudy results have shown that apartments' buildings in Amman are deficient, quantitatively and qualitatively, in both apartments with outdoor spaces in general and units on typical floors without outdoor space in specific. While, quantitative deficiency is associated with the poor layout in terms of area, functionality and variety. Qualitative is related to the absence of nature inspiration that incorporates five senses. As a result, this underlines the need for formulation design guidelines and strategies considering psychological wellbeing to improve outdoor spaces as a hub for activities.Originality/valueHighlight the value of introducing post-pandemic multi-family housing that could lead to changes in building codes and design strategies to enhance psychological wellbeing of residents.

Simple harpacticoid composition observed at deep hydrothermal vent sites on sea knoll calderas in the North-west Pacific

AbstractDirivultid copepods (Siphonostomatoida), one of the most successful meiobenthic organisms found at deep-sea hydrothermal vents, have been the focus of most previous ecological studies among meiofauna in these habitats. The ecology of Harpacticoida, a major benthic copepod group in typical deep-sea floor, however, is not well understood in terms of variations in community structure and controlling factors at venting sites. The spatial heterogeneities in benthic harpacticoid composition and their association with environmental parameters were investigated at hydrothermal vent chimney structures in the calderas of three neighbouring sea knolls (Bayonnaise Knoll, Myojin Knoll and Myojin-sho Caldera) in the western North Pacific. While a previous study had reported the distribution of dirivultids was strongly associated with spatial differences in stable carbon isotopic signatures (δ13C) of organic matter in the detritus on active chimneys in the field, multivariate analyses detected no significant corelation between the parameter and harpacticoid composition in this study. Instead, high associations of the harpacticoid composition with differences in water depth and total organic carbon (TOC) concentration were detected. Ectinosomatidae dominated at vent sites with lower TOC values in the shallowest Bayonnaise Knoll, while they were less prevalent at deeper vent fields in the other knolls, where Miraciidae was the most abundant family. This study indicated the availability of vent chemoautotrophic carbon is not a primary factor controlling the composition of harpacticoids even in the habitats on the hydrothermal vents, but instead by the food amount, regardless of its resources (including marine snow from the sea surface), in the study area.

Stability analysis of the milling process of the thin floor structures

Existing studies on analyzing the chatter problem in the milling process of the thin floors only included the dynamic responses of the cutter and the thin floors, however, the static lateral bending defections of the cutter also have actual effect on the stability of the process. This article develops a dynamic model to study the stability of the thin floor milling process by comprehensively considering the multi-flexibilities from both the static bending defections and the dynamic responses. The instantaneous dynamic chip thickness, which is required in the dynamic model, is analytically derived in the three-dimensional space by fully considering the following two factors. One is the bending effect induced by the static and dynamic deflections of the cutter in the X- and Y-directions, and the other is the tensing-compressing effect originated from the dynamic defections of the cutter and the workpiece in the Z-direction. At the same time, based on the substructure and sensitivity analysis theories, the in-situ dynamic parameters of the in-process floor, i.e. the natural frequency and the modal shape, are theoretically formulated by well combining the change of the cutter position with the removal of material. Based on the above derivations, the dynamic cutting forces together with the dynamic governing equation of the milling system are mathematically formulated, and then, the stability of the thin floor milling process is analyzed through solving the critical stability boundary. Finally, a series of milling tests are conducted on a typical thin floor structure to experimentally validate the accuracy and reliability of the proposed model.

Optimal design of sandwich floor panels made of high-strength composite materials considering stiffness constraints

The article considers the challenge of designing sandwich floor panels made of high-strength composites considering stiffness constraints. A dimensionless criterion is proposed for assessing the stiffness of floor panels. A new constraint equation determines an interrelation between geometrical parameters of composite constructions and a given criterion. A demo example and the results of designing a typical floor panel using a high-strength composite material are presented. The mass of a square meter of the structure is considered as an objective function, and the thickness of the skin and the height of the honeycomb core of a sandwich construction are considered as design variables. In order to find the optimal ratio of design variables, a graphical interpretation of the design problem is used considering strength and stiffness constraints in the design space. It is noted that the presence of restrictions on a given value of the permissible relative deflection leads to an increase in the required height of the honeycomb filler with an insignificant consumption of additional mass of the sandwich construction.

Effect of sustainable materials on embodied energy, carbon footprint and cost for a proposed conventional apartment

The construction industry accounts for an incredible 36% of worldwide energy usage, and 40% of CO2 emissions. Therefore, it is required to reduce the impact of construction on the environment. In this study, a few green materials have been selected along with few green techniques and are applied to the apartment and a comparison is provided. An ongoing project consisting of 18 typical floors and basement is selected for the study. Estimation of quantities are done according to the drawings and major materials such as blocks, internal paints, flooring and concrete are replaced with proposed sustainable materials. Embodied energy and carbon footprint analysis is performed for the building components such as blocks, tiles, paints, concrete and plastering. Alternate materials like compressed stabilized earth blocks, clay plaster, wallpaper, terrazzo tiles and blended cement concrete are chosen as replacements for the conventional materials. A comparison is provided with conventional materials with respect to the chosen sustainable materials. The results show 73% reduction in embodied energy and 52% reduction in carbon footprint of the structure. Also, reduction in cost by 30%. Hence, reducing the impact on the environment and making the structure sustainable.

A two-and-half dimensional finite element/boundary element model for predicting the vibro-acoustic behaviour of panels with poro-elastic media

Solid panels with additional poro-elastic materials are widely used in engineering, mainly for sound insulation. In many cases, the panels are constructed in such a way that they can be idealised to be infinitely long and uniform in one direction, forming a so-called two-and-a-half dimensional (2.5D) structure. Although the 2.5D finite element and boundary element methods (FEM-BEM) are particularly suitable for predicting the vibro-acoustic behaviour of such structures, up to now the presence of poro-elastic media have not been adequately considered. In this paper a 2.5D FE-BE vibro-acoustic model is presented which accounts for solids, fluids and poro-elastic media. The poro-elastic media are modelled using the 2.5D FE approach based on the mixed displacement-pressure formulation of Biot's theory. The solids are also modelled using the 2.5D FE method but based on the linear theory of elasticity. The internal fluids are modelled using the 2.5D FE method as well. For a flat panel, the external fluid on both sides of the panel can be modelled using the 2.5D BE method based on the Rayleigh integral. The coupling between the various sub-models is derived in detail. The accuracy of the model is demonstrated by applying it to simple multi-layered structures for which solutions can be produced using other well-established methods. It is demonstrated that the elasticity of the solid frame of a porous medium has a great influence on the vibro-acoustics of a structure containing the porous material. The method is then applied to investigate the sound transmission loss (STL) of a typical railway vehicle floor structure. Results show that STL can be greatly improved by proper arrangement of porous material layers between the interior wooden floor and the outer extrusion; however, the load bearing supporting beams may significantly reduce the benefit of the porous material layers.

Projected Rotational Velocities and Fundamental Properties of Low-mass Pre-main-sequence Stars in the Taurus–Auriga Star-forming Region

Abstract The projected stellar rotational velocity ( ) is critical for our understanding of processes related to the evolution of angular momentum in pre-main-sequence stars. We present measurements of high-resolution infrared and optical spectroscopy for 70 pre-main-sequence stars in the Taurus–Auriga star-forming region, in addition to effective temperatures measured from line-depth ratios, as well as stellar rotation periods determined from optical photometry. From the literature, we identified the stars in our sample that show evidence of residing in circumstellar disks or multiple systems. The comparison of infrared measurements calculated using two techniques shows a residual scatter of ∼1.8 km s−1, defining a typical error floor for the of pre-main-sequence stars from infrared spectra. A comparison of the distributions of stars with and without companions shows that binaries/multiples typically have a higher measured , which may be caused by contamination by companion lines, shorter disk lifetimes in binary systems, or tidal interactions in hierarchical triples. A comparison of optical and infrared values shows no significant difference regardless of whether the star has a disk or not, indicating that CO contamination from the disk does not impact measurements above the typical ∼1.8 km s−1 error floor of our measurements. Finally, we observe a lack of a correlation between the , presence of a disk, and H-R diagram position, which indicates a complex interplay between stellar rotation and evolution of pre-main-sequence stars.

Simulation of the Optimal Refrigerated Floor Design for Ice Rinks

A good design of the ice rink floor could save a great deal of capital and operational costs for hockey arenas. This ice rink floor design focuses on a cost-effective tube arrangement and an optimal concrete coverage over the tubes that could provide sufficient heat transfer rate between the coolant and the freezing ice. This paper reports a theoretical model to simulate the heat transfer characteristic of a different tube diameter, spacing distance, and thickness of the concrete coverage of the tubes of an ice rink. In addition, calcium chloride and ethylene glycol with water solutions are compared to figure out the pros and cons of these two secondary coolants. This model prediction is compared to the typical ice floor arrangement in order to determine the best floor construction scenario.

An analytical method to estimate temperature distribution of typical radiant floor cooling systems with internal heat radiation

Radiant floor cooling systems are increasingly used in practice. The temperature distribution on the floor surface and inside the floor structure, especially the minimum and average temperature of floor surface, determines the thermal performance of radiant floor systems. A good temperature distribution of the floor structure is very important to prevent occupant discomfort and avoid possible condensation in summer cooling. In this study, based on the heat transfer model of the single-layer homogeneous floor structure when there is no internal heat radiation in the room, this paper proposes a heat transfer model of single-layer floor radiant cooling systems when the room has internal heat radiation. Using separation variable methods, an analytical solution was developed to estimate temperature distribution of typical radiant floor cooling systems with internal heat radiation, which can be used to calculate the minimum temperature and the average temperature of typical composite floor structure. The analytical solution was validated by experiments. The values of the measured experiments are in a good agreement with the calculations. The absolute error between the calculated and the measured floor surface temperatures was within 0.45°C. The maximum relative error was within 2.31%. Prove that this model can be accepted. The proposed method can be utilized to calculate the cooling capacity of a typical multi-layer composite floor and will be developed in the future study for design of a typical radiant floor cooling system.

TDC-based horizontal leakage area estimation in multiunit residential buildings: Three correction factors

Infiltration and interzonal airflow driven by wind and stack interactions in a multi-unit residential building (MURB) are crucial factors affecting indoor air and environmental qualities. To analyze the weather-driven airflow in MURBs, it is essential to define accurately the horizontal leakage areas for serial airflow paths on typical and basement floors in the multizone airflow modeling. Considering the challenges in measuring numerous leakage areas, a horizontal leakage estimation method based on the thermal draft coefficient (TDC) is proposed, in which the leakage areas are calculated by the stack-driven pressure differences relatively easy to measure. Moreover, three correction coefficients are theoretically suggested to minimize the TDC uncertainties from (1) different household envelope areas, (2) horizontal temperature distributions on each floor, and (3) multiple shafts in real MURBs. Two validation studies were conducted in a real MURB. First, the TDC-based models were validated by CONTAMW, and the effectiveness of the three correction factors was shown in the simulation-based case. The envelope area ratio correction factor was most effective for leakage areas in dwelling units. The shaft ratio correction factor was necessary for elevator doors on typical floors and all leakage areas on basement floors. The air density correction factor could improve all leakage areas under the horizontal temperature distributions on each floor. Then, based on field measurements, the proposed method was applied to leakage estimation in the building. Compared with the existing method, the field-measurement-based validation case demonstrated a significant improvement in the leakage estimation under measurement uncertainties.

Toward complete area coverage of a reconfigurable tiling robot by following obstacle shape

Complete area coverage is a crucial factor for a floor cleaning robot. Self-reconfigurable tiling robots have been introduced over robots with a fixed shape for floor cleaning since they improve the area coverage by the flexibility of shape-shifting in cluttered environments. The existing coverage methods of reconfigurable tiling robots follow the tiling theory to cope with the area coverage problem. However, these methods merely consider a limited set of predefined shapes for the reconfiguration of a robot. The consideration of a limited set of predefined shapes for the reconfiguration impedes the ability of coverage to a certain extent in typical floor environments. Therefore, this paper proposes a novel method to improve area coverage of a tiling robot by reconfiguring according to the shape of obstacles. To this end, the required hinge angles for reconfiguring per the shape of an obstacle are determined by a genetic algorithm. The proposed method considers an optimized shape for reconfiguration in lieu of a limited set of predefined shapes. The coverage improvement of the proposed concept has been compared against the existing coverage methods of tiling robots to validate the performance. According to the experimental results, the proposed method surpasses the existing coverage methods of tiling robots from the perspective of area coverage, and the improvement is significant and noteworthy.

Improving the manufacturability of floor slabs by pre-installing elements that partially replace reinforced concrete and formwork

The article discusses well-known and perspective constructive and technological systems for the installation of monolithic and precast-monolithic floor slabs of civil and industrial buildings. It shows examples and expediency of using all kinds of inserts made of plastic and other light materials and products for replacing a part of heavy monolithic reinforced concrete. An original resource-saving method for the installation of precast-monolithic floor slabs with a simultaneous increase in the degree of their construction readiness is proposed. This effect is achieved by reducing their own weight and the use of permanent formwork. Reduction in own weight of the precast-monolithic floor slab is ensured by the use of volumetric lightweight trapezoidal or rectangular inserts, preferably made of expanded polystyrene, during its installation. The use of permanent formwork will eliminate the need for the subsequent performance of labor-intensive finishing and insulation works. To confirm the effectiveness of using the proposed method of precast-monolithic floor slab installation, the operation of two floor slabs was modeled in the LIRA SAPR computing complex - the proposed reinforced concrete innovative slab and a solid reinforced concrete slab. Having analyzed the calculated forces, deformations and the corresponding consumption of reinforcement and concrete, comparative indicators were obtained for the proposed innovative slab and for a typical solid floor slab. As a result, significant savings in material and cost have been proven.

Building Life Cycle Assessment to Evaluate Environment Sustainability of Residential Buildings in Sri Lanka

The built environment consumes significant amounts of natural resources and energy while being responsible for emitting huge quantities of carbon dioxide into the atmosphere and thereby to become as one of the main contributors for climate change. Therefore, identifying the nvironmental hotspots from the built environment has become important considering the entire life cycle of the building i.e. cradle-to-gate. Hence the importance of using Building Life Cycle Assessment (LCA) as a tool for evaluating environmental impacts related to the building sector is globally recognized. This paper presents an LCA for a case study of a typical single floor residential building located in Colombo, Sri Lanka. The system boundary of this study is considered as cradle-to-gate. The LCA model is developed using SimaPro 8.5.0. software tool. The results obtained from this LCA study highlighted that building walls as the most significant building component in terms of negative environmental impacts. Hence, more attention needs to be given to external and internal wall components to reduce negative environmental impacts. For further studies, it is recommended to measure the potential to reduce environmental impacts with the use of alternative construction materials and alternative construction practices for building walls in Sri Lanka.

Simulation Study on Fire Visibility of Typical Floor Planes of Modern Super High-Rise Office Buildings in China

With the development of office forms, the space form of super high-rise office buildings changed from the unitary efficient office space to a complex space that integrated office, communication, and experience, which also diversified the design of typical floors in the office zone. However, from the perspective of fire prevention, the placement of shared space changed the form of the plane in typical floors in the office zone, affecting the smoke spreading of fire and paths of personnel evacuation. Hence, the subject on the planar relationship among high-rise office buildings based on fire prevention analysis, which optimizes space design, is worthy of discussion. After collecting many cases of super high-rise office buildings in China, this study categorized them into six typical planes and adopted the software PyroSim for comparative simulation of the smoke spreading of fire. By comparing the visibility of different zones in fires, this study analyzed the effects of the area of the office zone, the location of the atrium, and the form of the plane on the fire visibility on the typical floor and put forth the key factors that influence fire visibility, thus optimizing the plane design of the typical floor of super high-rise buildings. The findings show that in the six fire scenes, the area of the office zone is between 1136m2 and 1736m2. The peak of duration for visibility decline at 1.5 m appeared in Scene 3. Its office zone is 1536m2, and the duration of visibility decline is greater than 1000 s. In other fire scenes, the duration of visibility decline is less than 300 s. By comparing the plane arrangement features of the fire scenes, the paper concludes that in a given fire scene, establishing an atrium in the office zone, expanding the length of the adjacent edge between the atrium and the office zone, and building an evacuation corridor between the atrium and the core tube can greatly extend the effective evacuation time. This can serve as reference for the plane design of super high-rise office buildings.

Learning from urban form to predict building heights.

Understanding cities as complex systems, sustainable urban planning depends on reliable high-resolution data, for example of the building stock to upscale region-wide retrofit policies. For some cities and regions, these data exist in detailed 3D models based on real-world measurements. However, they are still expensive to build and maintain, a significant challenge, especially for small and medium-sized cities that are home to the majority of the European population. New methods are needed to estimate relevant building stock characteristics reliably and cost-effectively. Here, we present a machine learning based method for predicting building heights, which is based only on open-access geospatial data on urban form, such as building footprints and street networks. The method allows to predict building heights for regions where no dedicated 3D models exist currently. We train our model using building data from four European countries (France, Italy, the Netherlands, and Germany) and find that the morphology of the urban fabric surrounding a given building is highly predictive of the height of the building. A test on the German state of Brandenburg shows that our model predicts building heights with an average error well below the typical floor height (about 2.5 m), without having access to training data from Germany. Furthermore, we show that even a small amount of local height data obtained by citizens substantially improves the prediction accuracy. Our results illustrate the possibility of predicting missing data on urban infrastructure; they also underline the value of open government data and volunteered geographic information for scientific applications, such as contextual but scalable strategies to mitigate climate change.

Sensitivity analysis of influence factors on multi-zone indoor airflow CFD simulation

Computational fluid dynamics (CFD) is a powerful tool for performing indoor airflow analysis. The simulation results are usually validated with measurement results for accuracy in reflecting reality. When conducting CFD for simulating air flow in a multiple-zone indoor environment with different boundary conditions in different regions, the validation of the CFD model becomes sophisticated. To improve the accuracy of the simulation, boundary conditions need to be adjusted based on how significant the influence factors are affecting the multi-zone CFD model, which few studies have been conducted on. The objective of this study is to investigate the impact of influence factors on temperature and carbon dioxide concentration distribution of a validated CFD model of a typical office floor using ANSYS Fluent. This study provides insights on how to fine-tune a complex model to reflect the actual air flow and how the air quality and human comfort in different zones on the same floor could be affected by influence factors. The influence factors investigated are: (1) size of door gaps, (2) solar radiation and (3) number and orientation of occupants. The velocity variations caused by different door gap sizes were studied for improving multi-zone simulation accuracy by adjusting door gap sizes. To study the significant impact of solar heat on multi-zone environment, the sensitivity of different regions of the office floor to solar heat amount and distribution was analyzed by conducting solar analysis under different weather conditions. Impact of occupants on temperature and carbon dioxide concentration distributions in multi-zone environment were investigated by considering different numbers and facing directions of occupants in different regions of the office floor. In addition, this study demonstrates how to modify the influence factors efficiently using building information modeling (BIM).