Floor Height Research Articles

Indoor environmental evaluation of traditional Chinese medicine clinic – taking the treatment space as an example

ABSTRACT Currently, there are no targeted standards and norms for Chinese medicine clinic diagnosis and treatment space. This study conducted field research in nine Chinese medicine clinics located in Hangzhou. The field research included the measurement of physical environment data in addition to the patients' subjective evaluation of the factors of the physical environment and design within the clinics, followed by statistical data analysis. The results show that the order of importance of physical environment factors in the diagnosis and treatment space was as follows: air quality > sound pressure level > humidity > temperature and the order of importance of the design factors were as follows: access route > supporting facilities > overall style > spatial scale > barrier-free design > cultural atmosphere and the order of importance of the spatial scale factors were as follows: area > the number of beds > window-to-wall ratio > floor height. The study presents the reference values of the physical environment parameters and spatial scale of the Chinese medicine clinics and the importance ranking of each factor.

Novel rod-sprung-mass model to investigate characteristics of building structural vibration induced by railways

Railway-induced vibrations in building structures require predictions to assess the serviceability. Fundamental properties such as the predominant modes of railway-induced vibrations are critical in structural design and mitigation approaches. However, the existing numerical models are customised to specific buildings. This renders these models unsuitable for broader mechanistic investigations. To address this, this study proposes a rod-sprung-mass (RSM) model to investigate the dynamic behaviour of structures under vertical ground excitations induced by railways. The columns were modelled as axial vibration rods, with each floor suspended on the rod as a sprung mass. The model was validated using a three-story steel frame structure and a five-story concrete structure. Subsequently, the dynamic characteristics of the structures and railway-induced responses were discussed. The structural vertical modes are attributed to the interaction between the columns and slabs, and the structural natural frequencies are outside the frequency range of the individual components. Parametric studies revealed that lower-order structural modes are generally predominant. Under such circumstances, the floor response tends to first decrease and subsequently increase with the floor height. As a result, low-rise buildings exhibit the maximum amplitude on the top floor, whereas the maximum amplitude is on the ground floor for high-rise buildings. Meanwhile, when structural high-order modes become predominant owing to a high-frequency input, the responses of the middle floors intensify, and the peak responses can be altered to the middle floors. This study emphasises the necessity of considering vertical global modes, whereas existing studies have focused mainly on mode shapes on particular floors. The RSM model is an efficient tool for structural design and vibration control.

An effective and efficient approach for smoke control in underground parking garages

Underground parking garages are enclosed spaces not directly exposed to the exterior. A smoke control system is typically required to facilitate occupants’ safe evacuation/relocation and assist in firefighting/rescue. Currently, there is a lack of guidelines for designing such systems in primary codes/standards. Only a limited number of local authorities have developed amendments to address this issue. These amendments either rely on outdated approaches, such as air change method, or simply repurpose carbon monoxide ventilation systems for smoke control without conducting additional engineering analysis and providing justification. The intent of this study is to examine the adopted approaches and explore an effective and efficient approach for garage smoke control. According to the study’s findings, it is discovered that garage floor height significantly impacts the performance of smoke control system. Additionally, structural components (beams) also influence the performance of smoke control system. Moreover, this study derives a linear equation to ascertain available safe egress time (ASET) when utilizing the carbon monoxide ventilation system or typical air change methods. Taking cost into consideration, the study concludes that for effective and cost-efficient smoke control in large underground garages, employing a carbon monoxide ventilation system is preferable to the traditional or equivalent air change method.

Analysis of seismic damage and seismic capacity of the structure of the ultrahigh pagoda

AbstractThe Chongwen Pagoda is the tallest masonry pagoda in China, with numerous openings inside the pagoda body. It is prone to damage during earthquakes, and the patterns of damage are complex. In order to scientifically analyze the dynamic performance, earthquake damage patterns, and mechanisms of the pagoda structure, on‐site dynamic testing was conducted to obtain the dynamic characteristics of the structure. A numerical model was established using Abaqus finite element software to calculate the dynamic characteristics of the structure. The results were compared with the testing results and showed a close agreement. El‐Centro earthquake wave, Taft earthquake wave, and Lanzhou artificial earthquake wave were selected as earthquake inputs based on site conditions, simulating frequent earthquakes, fortification earthquakes, and rare earthquakes with a magnitude of 9. The dynamic response of the pagoda structure was calculated, and the relationship between acceleration amplification factor, interstorey displacement, and interstorey displacement angle with floor height was analyzed. The seismic damage to the structure and the distribution of primary tensile stresses were studied, revealing the seismic damage mechanisms and the distribution characteristics of vulnerable areas in the Chongwen Pagoda. The research results provide references for the seismic assessment of this ancient pagoda.

Experimental and Numerical Investigation of Airflow Organization in Modular Data Centres Utilizing Floor Grid Air Supply

Under the background of “dual carbon” development goals, the rapid expansion of internet data centers driven by advancements in 5G technology has led to increased energy consumption and elevated heat densities within the server rooms in these facilities. In this study, the modular data center is taken as the research object for the purpose of figuring out a way to improve the thermal environment of the computer room, reduce power consumption, and ensure the safe and stable running of servers. To this end, this study established an airflow organization model for the modular data center and verified this model through experimental methods. Computational Fluid Dynamics (CFD) simulations were employed to investigate the effects of raised floor height, floor opening rate, and cold/hot air channel closure on airflow organization. Furthermore, the efficiency of airflow organization was evaluated using entransy loss metrics. The results show that optimal airflow conditions are achieved when the height of the raised floor is 600–800 mm, the opening rate is 40%, and the combined opening is 40%. Additionally, the closure of either the cold channel or both the cold and hot channels significantly improves airflow performance. Specifically, cold channel closure is recommended for new data centers with underfloor air supply systems, while combined cold and hot channel closure is suitable for data centers with high power density and extended air supply distances.

Three-dimensional volumetric assessment and stability of simultaneously placed implant following sinus floor augmentation with deproteinized human demineralized tooth matrix or deproteinized bovine bone mineral: a randomized controlled clinical trial.

This study aimed to analyze and compare three-dimensional volumetric bone changes and stability of simultaneously placed dental implants following sinus augmentation using deproteinized human demineralized tooth matrix (dpDTM) and deproteinized bovine bone mineral (DBBM). Twenty-four patients who required lateral maxillary sinus floor augmentation with simultaneous dental implant placement were randomly assigned to receive either dpDTM (n = 12) or DBBM (n = 12). Cone-beam computed tomography and resonance frequency analysis of implant stability were conducted immediately after surgery and 6 months postoperatively. Changes in the graft sinus floor and graft height volumes in the sagittal and coronal views, along with the implant stability quotient (ISQ), were analyzed and compared. Volumetric graft alteration was comparable between dpDTM (120.33 ± 77.48 mm3) and DBBM (108.51 ± 65.15 mm3) (p = 0.690). Reduction in the average graft height was also comparable: dpDTM group ranged from - 0.59 to - 0.93mm and the DBBM group ranged from - 0.55 to - 0.82mm (p > 0.05) at most examined levels. However, greater reduction in the mesial-graft height occurred in the dpDTM group (- 1.08 ± 0.70mm vs. -0.58 ± 0.39mm, p = 0.04). The ISQ values increased similarly in both groups to reach 70 at 6 months. dpDTM demonstrated comparable stability in graft volume and height during the healing process compared to DBBM and could serve as a viable alternative to DBBM for sinus floor augmentation with simultaneous implant placement.

Relationship between Learning Environment Design and Musculoskeletal Disorders in Learners

Introduction: Students spend most of their day at school sitting in their classroom furniture which is not quite the right size for students. This can be uncomfortable and even lead to back pain, leg cramps, and other problems. Method: Students’ body size for good posture while sitting, include popliteal to floor height, elbow to seat height, thigh thickness, sitting height, buttock to popliteal length, buttock to knee length, elbow to elbow breadth, the width of bitrochanter, subscapular height, and sitting shoulder height, and one standing is stature. Similarly, dimensions of chair-with-table, like seat height, the upper edge of the backrest, seat width, seat depth, table length, table width, table height, backrest height, and footrest currently used in the classroom were taken. The study compared students' anthropometry data with the furniture dimension data to obtain a match or mismatch between them with the help of standard mismatch equations. Results: The study reported that the mean body measurements of males are larger than females except for the width of bitrochanter. Seat width, seat depth, backrest height, and the upper edge of the backrest showed high mismatch percentages in students when patronising chairs. Table length reported high mismatch percentages among students. Conclusion: Using the users’ body sizes for furniture design will reduce musculoskeletal disorders and improve users’ sitting position. The recommended dimensions in furniture design will ergonomically fit students’ anthropometric measurements.

Experimental study of the out-of-plane mechanical properties of tall foam ceramic (FC) partition wall

Foamed ceramic (FC) partition wall is a non-structural component which has a broad application prospect. At present, most of the relevant specifications and studies on partition walls are limited to ordinary floor heights. In practical engineering applications, the partition wall exceeding the specification height limit often appears in scenes such as hotel halls and airport terminal. It would pose a life safety threat to the building in the event of out-of-plane damage of this type of partition wall under wind loads. Therefore, this paper aims to study the out-of-plane mechanical properties of tall FC partition walls under static loading. Experimental studies were conducted on the influence of different connection forms, as well as different construction column spacings on the out-of-plane mechanical performance of tall FC partition walls. It can be found that different connection forms had almost no effect on the cracking load. The cracking load decreased gradually with the increasing of the structural column spacings. The specimens with more rigid connection had better crack resistance ability during the service phase. With the increasing of the spacing of structural columns, the restraining effect of the steel skeleton on the FC wall panel, its out-of-plane bearing capacity and stiffness all decreased; The configuration of the steel skeleton reduced the brittleness of FC material; The weak part of tall FC partition wall was in the bonding area between FC wall panel and square steel tube, which should be paid attention to in practical engineering.

The construction of temporary and permanent housing after the Semeru eruption as a new strategy for post-disaster reconstruction

Mount Semeru in East Java erupted on December 4, 2021, which resulted in dozens of residents in Lumajang Regency dying and thousands of residents fleeing. The government is programming the rehabilitation of infrastructure and facilities, including reconstructing temporary and permanent housing for refugees. The research location is in the refugee relocation area in Sumbermujur Village, Candipuro District. In post-disaster reconstruction programs, permanent housings are built after temporary housings have been occupied for several months. However, in Lumajang Regency, the government accelerated the construction of permanent housing so that the developer completed the permanent housing earlier than the temporary housing. Two types of residential units were built simultaneously on a plot of site by different developers, so problems arose in combining the different housing types. After conducting literature studies and general observations, the researcher selected five cases for further observation. The criteria and technical specifications for temporary units are stated in Lumajang Regent Regulation Number 1 of 2022. The construction of permanent units uses RISHA technology. The two types of housing are planned to be directly connected in integration. This paper aims to explain the implementation of the construction of temporary and permanent housing and identify problems in combining the two types of housing in one plot. Researchers found four categories of issues, namely: differences in floor height at the connection between two building units, door and window openings that do not function because they meet the wall, two areas of the roof that are not connected properly, and there are gaps in the connection between units.

Passive Design Strategy in Vernacular House of Samin, Indonesia

Vernacular architecture embodies passive design principles and strategies to create comfortable dwellings. This study investigates the impact of passive design strategies on temperature comfort in Samin vernacular houses. Visual observation is employed to assess the suitability of house elements based on passive design criteria. At the same time, field measurements are conducted to evaluate comfortable temperature conditions using data loggers over one month. The research focuses on the Original Samin house and the New Samin house situated in Klopoduwur Village, Blora Regency, Central Java, Indonesia. The visual observation reveals that the roof volume, slope, and thin walls with low conductivity in both Samin houses align with passive design principles. The New Samin house also incorporates other passive design strategies, including an east-west building orientation with the long side perpendicular to the wind direction, an open-plan room layout, and varying floor heights. The temperature comfort performance in both houses falls within the neutral temperature range during 16 hours. The New Samin house exhibits the largest daytime air temperature decrease at 5.5°C, while the Original Samin house experiences the largest nighttime decrease at 0.7°C. The evolution of passive designs in Samin vernacular houses encompasses considerations such as building proportion and width, terrace width, positioning and size of window openings, vegetation, and shading elements.

Seismic response of irregular RC buildings designed for gravity and seismic loads

Irregular reinforced concrete framed buildings are peculiar and their seismic response is difficult to predict using simplified approaches. The irregularity in structural configuration is characterized by cross-sectional area reduction of the columns along the height, in-elevation and in-plan irregular distribution of the masses, complex floor geometry or floor geometry variation along the height. This study analyses the seismic response of several four-storey buildings with different types of irregularities, namely in-elevation floor height and floor geometry variation. Additionally, responses of both seismically designed and gravity load designed structures are compared for each geometry considered. A numerical model accounting for non-linear flexural and shear response of the structure is developed, aimed at conducting non-linear incremental dynamic analyses. The results are discussed in terms of inter-storey drift, floor acceleration profiles, fragility functions and floor response spectra. A significant influence of the irregularity on floor accelerations and displacements was observed, as well as on the spectral acceleration at collapse, mainly caused by mass and stiffness variation along the height. On the other hand, no significant influence was detected on failure modes.

Residential building and sub-building level flood damage analysis using simple and complex models

AbstractFlood damage assessment is critical for optimal risk management investments. Damage models evaluate physical damage or monetary loss from direct building exposure to flood hazard processes. Traditional models represent a simple relationship whereby physical damage increases with water depth. More complex models offer an improved understanding of vulnerability, analysing interactions between multiple hazard and exposure variables that drive damage. Our study investigates whether increasing model complexity and explanatory damage variables improves prediction precision and reliability at residential building and sub-building (component) levels. We evaluate simple and complex empirical univariable and multivariable models for flood damage prediction. The Random Forest algorithm learned on multiple hazard and exposure explanatory variables outperformed linear and non-linear univariable regression approaches. Random Forest model predictive precision was highest when learning was limited to water depth and several important explanatory damage variables (flow velocity, area and floor height). Component damage models demonstrated high predictive precision for internal finishes and services. Precision reduced for structure and external finishes as damage samples for model learning were limited. High performing but complex multivariable models require further spatio-temporal transfer investigation to determine opportunities for accurate and reliable object-specific flood damage prediction in data scarce locations.

Seismic performance analysis and control method of composite coupled shear wall with steel plate-fiber reinforced concrete coupling beams

This paper based on the study of steel plate-fiber reinforced concrete coupling beam components, designs a basic model of composite coupled shear walls with steel plate-fiber reinforced concrete coupling beams. The seismic performance of this model was numerically simulated using the ABAQUS finite element software, analyzing the stress distribution of various parts and the development pattern of plastic hinges in the structure. It also examines how factors such as axial compression ratio, coupling beam cross-sectional dimensions, single-sided wall limb aspect ratio, and total floor height affect the seismic performance of this type of coupled shear wall, providing a reasonable range for axial compression ratios and coupling ratios for composite coupled shear walls with steel plate-fiber reinforced concrete coupling beams. Based on the obtained reasonable axial compression ratio and coupling ratio, and using the analytical solution of the continuum method, a method for controlling the seismic performance of coupled shear wall structures was proposed. Results show that the composite coupled shear walls with steel plate-fiber reinforced concrete coupling beams exhibit high load-bearing capacity and lateral stiffness under inverted triangular horizontal loads, with good displacement ductility and strong energy dissipation capability, making it an excellent seismic performance coupled shear wall system. As the axial compression ratio increases, the displacement corresponding to the yield point and peak point of the structure gradually decreases, and the displacement ductility coefficient shows a trend of first increasing and then decreasing; it is recommended that when designing steel plate-fiber reinforced concrete coupling beam-coupled shear walls, the axial compression ratio should not exceed 0.3. Numerical analysis of coupling ratio-related parameters indicates that in high-intensity seismic design areas, the range of coupling ratios should be between 45% and 60%.

Modeling building carbon emissions by using MARS algorithm: A case of Istanbul

Controlling carbon emissions is critical to mitigating the negative environmental impacts of carbon emissions, such as global warming and climate change. Identifying the factors that affect building emissions is important because they contribute significantly to global emissions. The study aimed to determine the building characteristics that affect building emissions for residential buildings in Istanbul using the MARS algorithm. The MARS algorithm was also used to estimate building emissions based on the energy performance certificate data for each building. The study revealed that building characteristics have specific thresholds that affect building emissions differently depending on whether they are above or below these thresholds. The feature selection analysis revealed that the thermal insulation properties, specifically the wall_u value, roof_u value, and window_u value, had the greatest impact on building emissions. Other factors identified were building age, heating power, and floor height. These factors alone explain about 77 % of the building emissions. The analysis identified the interactions between building characteristics that affect building emissions. This enables common, appropriate solutions to be developed in terms of building characteristics to reduce building emissions.

Cost prediction of building projects using the novel hybrid RA-ANN model

PurposeAccurate and timely cost prediction is critical to the success of construction projects which is still facing challenges especially at the early stage. In the context of rapid development of machine learning technology and the massive cost data from historical projects, this paper aims to propose a novel cost prediction model based on historical data with improved performance when only limited information about the new project is available.Design/methodology/approachThe proposed approach combines regression analysis (RA) and artificial neural network (ANN) to build a novel hybrid cost prediction model with the former as front-end prediction and the latter as back-end correction. Firstly, the main factors influencing the cost of building projects are identified through literature research and subsequently screened by principal component analysis (PCA). Secondly the optimal RA model is determined through multi-model comparison and used for front-end prediction. Finally, ANN is applied to construct the error correction model. The hybrid RA-ANN model was trained and tested with cost data from 128 completed construction projects in China.FindingsThe results show that the hybrid cost prediction model has the advantages of both RA and ANN whose prediction accuracy is higher than that of RA and ANN only with the information such as total floor area, height and number of floors.Originality/value(1) The most critical influencing factors of the buildings’ cost are found out by means of PCA on the historical data. (2) A novel hybrid RA-ANN model is proposed which proved to have the advantages of both RA and ANN with higher accuracy. (3) The comparison among different models has been carried out which is helpful to future model selection.

Seismic and Wind Resillence Study of a 15 Story High-Rise Building with Floating Columns in Seismic Zones II & V

The use of floating columns in the construction of high-rise buildings, specifically in the context of G+15 structures in metropolitan cities, as per Indian standards. The structural design of a building is crucial for its durability, strength, stability, and lifespan. Floating columns play a significant role in transferring loads from the floors to the beams, affecting the overall stability of the building.Several factors impact the structural design, including bending moments, shear forces, torsion, and deflection. Due to the growing population in metropolitan areas, there is a need for high-rise buildings that can accommodate both commercial and residential spaces on a single platform. Commercial and residential floors have different load requirements. Therefore, floating columns are specifically used for residential floors to address these varying load demands. The structural analysis considers seismic and wind forces as per Indian standards (IS 1893-2016 for seismic analysis and IS 875-2015 for wind analysis) for different seismic zones (Zone- Ⅱ, Ⅲ, Ⅳ, and Ⅴ). The materials used in the construction include concrete with a grade of M40 and steel with a grade of Fe550. These material grades are commonly used in construction for their respective strength properties. The floor height for residential floors is 3 meters, while commercial floors have a height of 4 meters. This distinction in floor height is considered in the structural design. The design of high-rise buildings, especially in seismic-prone regions, requires a thorough understanding of structural engineering principles and adherence to local building codes and standards to ensure the safety and stability of the structure. The use of floating columns can be a part of a structural design strategy to address varying load requirements in different parts of the building.Safety is paramount in the design and construction of high-rise buildings, particularly in areas susceptible to seismic activity and strong winds.

Developing preliminary cost estimates for foundation systems of high-rise buildings

This study provided a unique Artificial intelligence (AI) model for the cost estimation of the foundation system for high-rise buildings. First, parametric data research was conducted, including 180 examples of foundation systems for high-rise building models related to criteria such as average column spacing, floor height, slap load, overall weight, base shear, and over. In addition, moment, gravity load, seismic load, design load, various columns (mid-edge-corner), soil profile, bearing capacity, GWT, excavation depth, and foundation systems are all factors to consider (shallow and deep footing). The research encompassed column spacing (5.0, 7.0, and 9.0 m) and the number of stories from 15 to 35, with an average cost decrease of 15%. The AI model utilizes extensive machine learning algorithms to analyze structural and geotechnical parameters. It provides a predictive tool that improves decision-making in the preliminary design. The methodology includes collecting data, training models utilizing innovative neural network techniques and validating them against current cost estimation models. The findings indicate that the AI model significantly improves the accuracy of cost estimations, with a precision rate of 95%, compared to traditional methods. Moreover, the model presents a potential cost savings of up to 15%. Construction designers and decision-makers may utilize the study’s findings to increase the accuracy of foundation system selection, lower costs and construction length, and improve overall project performance. Future work may involve applying this concept to infrastructure and substructure projects and collecting more data for benchmarking and empirical study.

ThermoBounce: Visualizing Chemical Kinetics via a Gravitational Potential Analogy

ThermoBounce is an interactive online visualization designed to help students understand how enthalpy, entropy, and temperature contribute to the reaction rate and equilibrium of a unimolecular chemical change between reactant and product states, for example, molecular isomerizations or phase transitions. At the start of the animation, reactant molecules are represented by spheres bouncing around in a reactant room, with an average kinetic energy proportional to the temperature. This room is connected to an adjacent product room by a window. When the user triggers the animation, spheres may convert to the product state by passing through the window into the product room, changing color as they do so. The difference between the floor heights of the reactant and product rooms represents the enthalpy change of the reaction, and the floor areas of the two rooms represent the entropies of the reactant and product states. The height of the bottom of the window above the floor of the reactant room represents the enthalpy of activation, and the width of the window represents the entropy of activation. Users can change the geometry of the rooms and window to adjust all these quantities and can modify the temperature before or during the reaction. They can then observe the resulting changes in the reaction rate and in the accumulation of product molecules, as shown on a reaction progress graph. The visualization and instructions for interacting with it are freely available on the Internet.

Investigation of the Causes of Soft-Storey and Weak-Storey Formations in Low- and Mid-Rise RC Buildings in Türkiye

This study investigates the causes of soft-storey and weak-storey formations in low- and mid-rise RC (Reinforced Concrete) buildings in Türkiye. In the first phase of the study, 96 model buildings were designated for the examination of soft-storey irregularity when the ground floors are used for commercial purposes and the upper floors for residential use. The ground floor heights that would cause soft-storey irregularity in each of the selected buildings were determined according to the formulas given in the Türkiye Building Earthquake Code (TBEC) and the American Society of Civil Engineers Standard (ASCE). It was found that the ground floor heights obtained according to ASCE are usable in practice, whereas those obtained according to the TBEC, particularly for buildings over three storeys, are excessively high for practical use. This indicates that, even if the buildings in Türkiye are designed with very high ground floor heights, they do not have soft-storey irregularities, according to the TBEC, but soft-storey formation may occur in these buildings due to the high ground floor height as a result of the effects of earthquakes. Instead of the soft-storey irregularity coefficient limit value (nki > 2) found in the TBEC, this study proposes a new limit value to prevent the design of buildings with very high ground floors. In the second phase of the study, for the purpose of examining weak-storey irregularity, 105 model buildings differing in their infill wall layout, number of spans, span length, and number of storeys were selected. The weak-storey irregularity coefficients of each of these models were determined according to the TBEC. The results of the study revealed that buildings with no infill walls in one direction or with infill walls in only one of the exterior axes in one direction have a high risk of having weak storeys.

Cost Overrun and Delays in Construction Management by Using Primavera

Abstract: Project management is the practice of organizing, planning, carrying out, overseeing, and wrapping up a team's work in order to accomplish particular objectives and satisfy particular success criteria within a given time frame. Each project is unique, and managing it is necessary to meet the project's need for increased productivity. Notwithstanding the centuries-long evolution of the construction industry and the decades-long quest for novel solutions by researchers, a variety of obstacles still need to be overcome in order to improve the speed, safety, affordability, and accuracy of the construction process. Utilizing a program called Prima Vera p6, which is a tool for project planning and progress tracking, the study focuses on an ongoing residential building construction project (G+5) . This project is a G+5 storey residential building with a rectangular shape RCC framed construction with a total size of 1391 Sq. Mtr. And the floor height is 3m. We used Primavera to calculate project quantities, schedule, and estimate the project. We created a Gantt chart and a network diagram for this project and completed it in a timely and cost-effective manner. It gathers all relevant data from the relevant agencies and closely monitors the work processes. Through our work on it, we have learned a great deal about the challenges that businesses encounter on a daily basis. Though every project is unique, as I've already shown, we may learn from our mistakes and prevent them in future endeavors. Using Primavera P6, a project management tool, a comparison of the original and actual time and cost is conducted in this study. The project monitoring process itself might not be completed effectively even with well-established planning and policies.