Building operations-that is,the continual activities and processes required to manage and maintain buildings-are responsible for approximately 30% of global energy use and 26% of carbon dioxide(CO_(2))emissions.
Buildings are crucial for achieving carbon reduction and mitigating climate change.China's dual-carbon strategy includes ambitious goals for carbon peaking and carbon neutrality in the building sector.However,clea...Buildings are crucial for achieving carbon reduction and mitigating climate change.China's dual-carbon strategy includes ambitious goals for carbon peaking and carbon neutrality in the building sector.However,clear technical pathways and roadmaps for achieving these objectives remain lacking.In this study,we examined the trajectory and characteristics of energy consumption and emissions in China's building sector and conducted future scenario analyses informed by global comparative studies.Ecological development pathways were proposed as target scenarios to achieve carbon neutrality in the building sector.Detailed pathways to achieve carbon neutrality were delineated,covering various tasks and timelines.These included managing building stocks,improving energy efficiency and sufficiency,promoting electrification,implementing photovoltaic-energy storage-direct current-flexibility(PEDF)buildings,decarbonizing heating systems,and developing new energy systems for rural areas.In addition,we discussed and recommended policy measures to enhance building service provisions within the framework of the ecological development concept and promote key technologies within the context of a low-carbon energy system transition.The findings of this study provide high-level recommendations for policymakers in the building and energy sectors and offer insights into technological perspectives and development targets for future research and engineering practice.展开更多
Quality management in building curtain wall construction covers both the essence and scope,including material control and process control.It is crucial for safety,longevity,and energy efficiency.Although quality manag...Quality management in building curtain wall construction covers both the essence and scope,including material control and process control.It is crucial for safety,longevity,and energy efficiency.Although quality management models are diverse,they have their limitations.The paper also discusses key points such as quality issues,material and process compatibility,and node construction,along with various techniques and management methods to improve quality.It also highlights areas for further research and future directions.展开更多
This paper will report on the development of a prototype of actively controlled facade module,which is capable of adapting its solar transmittance to changeable solar gains.Hence this new facade offers additional feat...This paper will report on the development of a prototype of actively controlled facade module,which is capable of adapting its solar transmittance to changeable solar gains.Hence this new facade offers additional features with respect to the most popular currently used glass facades,which have fixed solar transmittance indeed.The novel technology is made possible by the creation of an additional 1.5-mm-thick sliding shielding liquid,which flows internally,in order to dynamically adapt the window’s solar transmittance.As compared with competitive technologies,this shielding system has low manufacturing costs,is durable,is completely reversible and always transparent,irrespective of its transmittance state.Specifically,the manufacture of a full-size window prototype and the engineering of the window was carried out;moreover,glass pane bending when subject to hydrostatic pressure was eventually assessed.All this information has been used to set up the industrial process needed for its manufacturing.展开更多
A novel Additive Manufacturing(AM)-driven concurrent design strategy based on the beam characterization model considering strength constraints is proposed.The lattice topology,radius size,Building Orientation(BO),and ...A novel Additive Manufacturing(AM)-driven concurrent design strategy based on the beam characterization model considering strength constraints is proposed.The lattice topology,radius size,Building Orientation(BO),and structural yield strength can be simultaneously adjusted by integrating the overall process-structure-performance relationship of the AM process into the optimization.Specifically,the transverse isotropic material model is adopted to describe the material properties induced by the layer-by-layer manner of additive manufacturing.To bolster lattice strength performance,the stress constraints and ratio constraints of lattice struts are employed.The Tsai-Wu yield criterion is implemented to characterize the lattice strut's strength,while the P-norm method streamlines the handling of multiple constraints,minimizing computational overhead.Moreover,the gradient-based optimization model is established,where both the individual struts diameters and BO can be designed,and the buckling-prone spatial struts are strategically eliminated to improve the lattice strength further.Furthermore,several typical structures are optimized to verify the effectiveness of the proposed method.The optimized results are quite encouraging since the heterogeneous lattice structures with optimized BO obtained by the strength-based concurrent method show a remarkably improved performance compared to traditional designs.展开更多
Substantially glazed facades are extensively used in contemporary high-rise buildings to achieve attractive architectural aesthetics.Inherent conflicts exist among architectural aesthetics,building energy consumption,...Substantially glazed facades are extensively used in contemporary high-rise buildings to achieve attractive architectural aesthetics.Inherent conflicts exist among architectural aesthetics,building energy consumption,and solar energy harvesting for glazed facades.In this study,we addressed these conflicts by introducing a new dynamic and vertical photovoltaic integrated building envelope(dvPVBE)that offers extraordinary flexibility with weather-responsive slat angles and blind positions,superior architectural aesthetics,and notable energy-saving potential.Three hierarchical control strategies were proposed for different scenarios of the dvPVBE:power generation priority(PGP),natural daylight priority(NDP),and energy-saving priority(ESP).Moreover,the PGP and ESP strategies were further analyzed in the simulation of a dvPVBE.An office room integrated with a dvPVBE was modeled using EnergyPlus.The influence of the dvPVBE in improving the building energy efficiency and corresponding optimal slat angles was investigated under the PGP and ESP control strategies.The results indicate that the application of dvPVBEs in Beijing can provide up to 131%of the annual energy demand of office rooms and significantly increase the annual net energy output by at least 226%compared with static photovoltaic(PV)blinds.The concept of this novel dvPVBE offers a viable approach by which the thermal load,daylight penetration,and energy generation can be effectively regulated.展开更多
To meet the challenge of mismatches between power supply and demand,modern buildings must schedule flexible energy loads in order to improve the efficiency of power grids.Furthermore,it is essential to understand the ...To meet the challenge of mismatches between power supply and demand,modern buildings must schedule flexible energy loads in order to improve the efficiency of power grids.Furthermore,it is essential to understand the effectiveness of flexibility management strategies under different climate conditions and extreme weather events.Using both typical and extreme weather data from cities in five major climate zones of China,this study investigates the energy flexibility potential of an office building under three short-term HVAC management strategies in the context of different climates.The results show that the peak load flexibility and overall energy performance of the three short-term strategies were affected by the surrounding climate conditions.The peak load reduction rate of the pre-cooling and zone temperature reset strategies declined linearly as outdoor temperature increased.Under extreme climate conditions,the daily peak-load time was found to be over two hours earlier than under typical conditions,and the intensive solar radiation found in the extreme conditions can weaken the correlation between peak load reduction and outdoor temperature,risking the ability of a building’s HVAC system to maintain a comfortable indoor environment.展开更多
The present study investigates the influence of embedment depth of isolated footing supporting moment-resisting frame buildings through scaled-down tests.These experiments utilize scaled models representing different ...The present study investigates the influence of embedment depth of isolated footing supporting moment-resisting frame buildings through scaled-down tests.These experiments utilize scaled models representing different building aspect ratios and footing embedment depths.All the model tests are subjected to scaled-down input ground motions of different intensities and magnitudes.These model tests are performed in laminar shear containers through shake table testing.The results obtained for different cases of soil-foundation-structure systems and fixed-base conditions are expressed in terms of natural frequency,peak spectral acceleration,frequency response,lateral deformation,inter-storey drifts,and rocking of the foundation.The analysis reveals that the natural frequency of the coupled system on isolated footings diminishes by 27.52%–58.21%relative to fixed-base conditions,highlighting the significance of accounting for soil-foundation-structure interaction effects.Moreover,a notable increase of 52.97%in the natural frequency of the coupled system is observed as the embedment depth of the footing increases from 0.75 to 6.Additionally,the study demonstrates that the inter-storey drift of the 5-storey building remains well within acceptable limits under dense soil conditions.Consequently,within the parameter range explored in this research,the study concludes that soil-foundation-structure interaction effects are insignificant for low-rise buildings(H≤15 m)supported on isolated footings during seismic events.展开更多
Vacuum glazing is highly regarded for its ability to transmit light while providing heat preservation,sound insulation,lightweight characteristics,and resistance to condensation.Scholars have made significant strides ...Vacuum glazing is highly regarded for its ability to transmit light while providing heat preservation,sound insulation,lightweight characteristics,and resistance to condensation.Scholars have made significant strides in the study of vacuum glazing through their notable efforts.This study systematically reviewed vacuum glazing and its composite structures,including material selection,fabrication techniques,research methods,and performance evaluation.This review initially presented fundamental techniques for preparing vacuum glazing,with a focus on edge seal and support pillar arrangements,and introduced common composite structures such as hybrid and tinted vacuum glazing.Furthermore,this review summarized the analytical,numerical,and experimental methodologies used to assess the thermal performance of vacuum glazing.This study also outlined heat transfer coefficients associated with various vacuum glazing structures,investigated the influence of different parameters on their heat transfer coefficients,and evaluated their potential for energy conservation across diverse climatic regions.Finally,the research delineated future trends in the advancement of vacuum glazing to provide guidance for both theoretical studies and practical applications in industry.This research serves as a valuable resource for both theoretical exploration and practical integration of vacuum glazing,facilitating its improvement and optimization to advance sustainable low-carbon building practices.展开更多
Pressure has been introduced into power systems owing to the intermittent and uncertain nature of renewable energy.As a result,energy resource aggregators are emerging in the electricity market to realize sustainable ...Pressure has been introduced into power systems owing to the intermittent and uncertain nature of renewable energy.As a result,energy resource aggregators are emerging in the electricity market to realize sustainable and economic advantages through distributed generation,energy storage,and demand response resources.However,resource aggregators face the challenge of dealing with the uncertainty of renewable energy generation and setting appropriate incentives to exploit substantial energy flexibility in the building sector.In this study,a risk-aware optimal dispatch strategy that integrates probabilistic renewable energy prediction and bi-level building flexibility engagements is proposed.A natural gradient boosting algorithm(NGBoost),which requires no prior knowledge of uncertain variables,was adopted to develop a probabilistic photovoltaic(PV)forecasting model.The lack of suitable flexibility incentives is addressed by a novel interactive flexibility engagement scheme that can take into account building users'willingness and optimize the building flexibility provision.The chance-constrained programming method was applied to manage the supply-demand balance of the resource aggregator and ensure risk-aware decision-making in power dispatch.The case study results show the strong economic and environmental performance of the proposed strategy.The proposed strategy leads to a win-win situation in which profit increases through a load reduction of 13% and a carbon emission reduction of 3% is achieved for different stakeholders,which also shows a trade-off between the economic benefits and the risk of supply shortage.展开更多
In an environment where demand for housing is growing and the supply from public authorities is virtually non-existent,several mechanisms for housing production are emerging in the formal,semi-informal and informal co...In an environment where demand for housing is growing and the supply from public authorities is virtually non-existent,several mechanisms for housing production are emerging in the formal,semi-informal and informal construction sectors.The project owner wonders how much it costs to construct a building to an acceptable standard.Cost forecasting in general faces a number of difficulties,including a lack of available information during the preliminary phase of the project.As such,estimation becomes a crucial task involving great responsibility,which can lead to either more convincing results or chaotic situations.This study proposes a quick and effective method for estimating the cost of a single-storey F4 residential building.The modelling is done using multiple linear regression based on a statistical approach applied to twenty(20)projects that have already been completed.The project data are collected from design offices in the city of Brazzaville.The method expresses the cost of an F4 construction by certain project tasks,representing five(5)variables,three(3)of which are related to structural work and two(2)to finishing work,which are easy to determine.This approach,known as MECSO(Cost Estimation Model by Sub-structure),gives good results in all statistical tests carried out with reasonable confidence intervals.This method is very practical for engineering professionals working on the evaluation and control of construction costs.展开更多
Ventilation is an effective solution for improving indoor air quality and reducing airborne transmission.Buildings need sufficient ventilation to maintain a low infection risk but also need to avoid an excessive venti...Ventilation is an effective solution for improving indoor air quality and reducing airborne transmission.Buildings need sufficient ventilation to maintain a low infection risk but also need to avoid an excessive ventilation rate,which may lead to high energy consumption.The Wells-Riley(WR)model is widely used to predict infection risk and control the ventilation rate.However,few studies compared the non-steady-state(NSS)and steady-state(SS)WR models that are used for ventilation control.To fill in this research gap,this study investigates the effects of the mechanical ventilation control strategies based on NSS/SS WR models on the required ventilation rates to prevent airborne transmission and related energy consumption.The modified NSS/SS WR models were proposed by considering many parameters that were ignored before,such as the initial quantum concentration.Based on the NSS/SS WR models,two new ventilation control strategies were proposed.A real building in Canada is used as the case study.The results indicate that under a high initial quantum concentration(e.g.,0.3 q/m^(3))and no protective measures,SS WR control underestimates the required ventilation rate.The ventilation energy consumption of NSS control is up to 2.5 times as high as that of the SS control.展开更多
Accurate basic data are necessary to support performance-based design for achieving carbon peak and carbon neutral targets in the building sector.Meteorological parameters are the prerequisites of building thermal eng...Accurate basic data are necessary to support performance-based design for achieving carbon peak and carbon neutral targets in the building sector.Meteorological parameters are the prerequisites of building thermal engineering design,heating ventilation and air conditioning design,and energy consumption simulations.Focusing on the key issues such as low spatial coverage and the lack of daily or higher time resolution data,daily and hourly models of the surface meteorological data and solar radiation were established and evaluated.Surface meteorological data and solar radiation data were generated for 1019 cities and towns in China from 1988 to 2017.The data were carefully compared,and the accuracy was proved to be high.All the meteorological parameters can be assessed in the building sector via a sharing platform.Then,country-level meteorological parameters were developed for energy-efficient building assessment in China,based on actual meteorological data in the present study.This set of meteorological parameters may facilitate engineering applications as well as allowing the updating and expansion of relevant building energy efficiency standards.The study was supported by the National Science and Technology Major Project of China during the 13th Five-Year Plan Period,named Fundamental parameters on building energy efficiency in China,comprising of 15 top-ranking universities and institutions in China.展开更多
Building buffer zone space is not only one of essential approaches for better mental quality of interior building space, but also an important factor that may influence interior thermal comfort and energy consumption....Building buffer zone space is not only one of essential approaches for better mental quality of interior building space, but also an important factor that may influence interior thermal comfort and energy consumption. This study aims to analyze regulative advantages of buffer zone to the surrounding functional spaces. Based on a fieldwork test in a typical office building in cold climate zone in Beijing,China,the monitor data show interior physical performance in the Winter. The research selects two types of different buffer zones in the same building. One is a south-faced greenhouse which has large dimension with plenty of vegetation,and the other is a simple atrium in the middle of five floor building with mount of skylights. The factors and their influence to surrounding functional spaces and the whole building are found out from the comparisons of collected data by floor to floor monitor test on both buffer zones at the same time. The comparisons of two types of buffer zones conclude that the greenhouse is more effective to air quality regulation but not so clearly wellperformed to thermal buffering as expected due to the dominate active central heating in the Winter. This fieldwork test results for building performance can be helpful for both architects and engineers in the early phase of sustainable design.展开更多
Multi-dimensional heat transfers modeling is crucial for building simulations of insulated buildings,which are widely used and have multi-dimensional heat transfers characteristics.For this work,state-model-reduction ...Multi-dimensional heat transfers modeling is crucial for building simulations of insulated buildings,which are widely used and have multi-dimensional heat transfers characteristics.For this work,state-model-reduction techniques were used to develop a reduced low-order model of multi-dimensional heat transfers.With hot box experiment of hollow block wall,heat flow relative errors between experiment and low-order model predication were less than 8% and the largest errors were less than 3%.Also,frequency responses of five typical walls,each with different thermal masses or insulation modes,the low-order model and the complete model showed that the low-order model results agree very well in the lower excitation frequency band with deviations appearing only at high frequency.Furthermore,low-order model was used on intersection thermal bridge of a floor slab and exterior wall.Results show that errors between the two models are very small.This low-order model could be coupled with most existing simulation software for different thermal mass envelope analyses to make up for differences between the multi-dimensional and one-dimensional models,simultaneously simplifying simulation calculations.展开更多
This paper presents a study to optimize the heating energy costs in a residential building with varying electricity price signals based on an Economic Model Predictive Controller (EMPC). The investigated heating syste...This paper presents a study to optimize the heating energy costs in a residential building with varying electricity price signals based on an Economic Model Predictive Controller (EMPC). The investigated heating system consists of an air source heat pump (ASHP) incorporated with a hot water tank as active Thermal Energy Storage (TES), where two optimization problems are integrated together to optimize both the ASHP electricity consumption and the building heating consumption utilizing a heat dynamic model of the building. The results show that the proposed EMPC can save the energy cost by load shifting compared with some reference cases.展开更多
Building defect is an issue in existing buildings that needs urgent tackling to prevent further problems. This study assessed the defects in concrete elements in residential buildings of 30 years and above in the Onit...Building defect is an issue in existing buildings that needs urgent tackling to prevent further problems. This study assessed the defects in concrete elements in residential buildings of 30 years and above in the Onitsha metropolis of Anambra State, Nigeria. Data collection instruments in the study include structured questionnaire, interviews, visual inspection/observations, archival records, recordings, photographs;and non-destructive testing of the concrete elements in an existing building in the study area. The population of this study constituted of the construction registered professionals and the existing buildings in study area. The sample for the study was based on the calculated sample size using Taro Yamani Formula. A total of 158 registered professionals were sampled from the population of 260. The questionnaires were purposively distributed to the registered professionals up to the required sample sizes of 158 and 129 questionnaires were properly filled and returned. The study used the SPSS and Microsoft Excel to analyze the data. The results were analyzed in percentages and figures using descriptive statistics and presented in the form of pie charts and tables. The finding of the study revealed that the causes and effects of structural defects on the concrete elements in existing buildings in the study area according to the rating are;exposed/corrosion of the embedded metals, faulty workmanship, overload and impacts, chemical attack, freeze-thaw deterioration, fire/heat, restraint to volume change. The visual observation revealed that the structural elements are characterized by heavy defects such as deep vertical, horizontal and diagonal cracks, exposed/ corrosion of the embedded metals, spalling of the concrete slabs. The existence of defects in the concrete members led to the low compressive strength of the concrete elements and the structural instability of the existing buildings as revealed by the non-destructive test. The non-destructive test result revealed that most of the tested concrete elements have low compressive strength value and such were remarked poor as they did not satisfy the assumed value. Essentially, the study concluded by recommending that regular monitoring, inspections and non-destructive testing of concrete elements should be conducted on existing aged and defected buildings to detect the structural stability of the buildings;and it is imperative to evacuate occupants from heavy structurally deteriorated and defected buildings since most of them have lost their residual design life span and ability to sustain imposed loads.展开更多
The proliferation of multi-family residential building in Anambra State of Nigeria due to increasing demand without recourse to performance has broughtconcerns about the adequacy and sustainability of this housing typ...The proliferation of multi-family residential building in Anambra State of Nigeria due to increasing demand without recourse to performance has broughtconcerns about the adequacy and sustainability of this housing type.This study therefore,assessed the adequacy and sustainability performance of multi-family residential buildings in urban areas of Anambra State.The study sampled the opinions of 384 households living in multi-family residential buildings through a questionnaire survey.We conducted data analysis based on 214 responses that were useful for analysis.The study found that internal and building component variables and supporting neigh-borhood variables were adequate,but the surrounding environment variables were inadequate based on Mean Score Index.However,based on Sustainability Performance Index,the occupant sperceived social sustainability performance of the buildings as satisfactory,while environmental and economic sustainability performance were perceived as fairly satisfactory.The Pearson correlation coefficient result further established that adequacy of internal and building component variables was significantly and positively related to the residents'perceived social sustainability performance.Adequacy of the surrounding environmental variables was also found to be positively and significantly related to the residents'perceived environmental sustainability performance,whereas adequacy of supporting neighborhood facilities was found to be negatively and significantly related to the residents’perceived economic sustainability performance.This sug-gested that investors and owners of multi-family residential buildings should direct more efforts towards improving the surrounding environment to supplements other facilities and increase the economic benefit of the renters or occupiers with increasing economic sustainability performance in terms of value for money.展开更多
Riyadh city is the fastest growing city in Saudi Arabia. The rapid urban growth that happened recently in Riyadh was not based on the traditional urban planning principles, which have been established and applied for ...Riyadh city is the fastest growing city in Saudi Arabia. The rapid urban growth that happened recently in Riyadh was not based on the traditional urban planning principles, which have been established and applied for the city development process. The imported building regulations have created a new urban structures and street patterns. The contemporary urban form in Riyadh city is based mainly on traffic and economic consideration with the neglect of environmental dimensions. This research aims to examine the impacts of building regulations on the thermal performance of residential buildings in Riyadh city, with the ultimate goal of establishing planning guidelines that consider the environmental conditions of the city. The methodology adopted for achieving the aim of this study consists of two phases. First, the literature related to building regulations development in Riyadh, as of 2018, was reviewed. Second, buildings energy simulation was conducted to examine the thermal performance of the typical current status of residential building blocks in Riyadh city, and then several changes to building regulations were made to investigate their impacts on the thermal performance of buildings. The results showed that the impacts of Riyadh building regulations on the thermal performance of residential buildings differ across the evaluated cases. The ratio of building height to street width, urban block street orientation, and building orientation are the main factors affecting thermal performance of buildings within urban block. The study also concludes that adjusting the ratio of building height to the distance between buildings could have a significant impact in reducing cooling loads. This study will help policy makers, planners and designers to investigate the shortcoming in the current building regulations.展开更多
Decarbonization in operational residential buildings worldwide has become critical in achieving the carbon neutral target due to the growing household energy demand.To accelerate the pace of global carbon neutrality,t...Decarbonization in operational residential buildings worldwide has become critical in achieving the carbon neutral target due to the growing household energy demand.To accelerate the pace of global carbon neutrality,this study explores the operational carbon change in global residential buildings through the generalized Divisia index method and decoupling analysis,considering the decarbonization levels of residential buildings at different scales.The results show that(1)most of the samples showed a decrease in the total emissions from 2000 to 2019.Except for China and the United States(US),the carbon emissions in global residential building operations decreased by 7.95 million tons of carbon dioxide(MtCO_(2))per year over the study period.Emissions per gross domestic product(GDP)was the most positive driver causing the decarbonization of residential buildings,while GDP was the most negative driver.(2)Carbon intensity was essential to achieving a strong decoupling of economic development and carbon emissions.The US almost consistently presented strong decoupling,while China showed weak decoupling over the last two decades.(3)The pace of decarbonization in global residential building operations is gradually slowing down.From 2000 to 2019,decarbonization from residential buildings across 30 countries was 2094.3 MtCO_(2),with a decarbonization efficiency of 3.4%.Overall,this study addresses gaps in evaluating global decarbonization from operational residential buildings and provides a reference for evaluating building decarbonization by other emitters.展开更多
文摘Building operations-that is,the continual activities and processes required to manage and maintain buildings-are responsible for approximately 30% of global energy use and 26% of carbon dioxide(CO_(2))emissions.
基金supported by the National Natural Science Foundation of China(52478095 and 72261147760)the Chinese Academy of Engineering Project"Low-Carbon Transition Strategy and Pathways for Urban and Rural Energy Supply Systems in China"(2023-XBZD-07)the China Postdoctoral Science Foundation(GZC20240874)。
文摘Buildings are crucial for achieving carbon reduction and mitigating climate change.China's dual-carbon strategy includes ambitious goals for carbon peaking and carbon neutrality in the building sector.However,clear technical pathways and roadmaps for achieving these objectives remain lacking.In this study,we examined the trajectory and characteristics of energy consumption and emissions in China's building sector and conducted future scenario analyses informed by global comparative studies.Ecological development pathways were proposed as target scenarios to achieve carbon neutrality in the building sector.Detailed pathways to achieve carbon neutrality were delineated,covering various tasks and timelines.These included managing building stocks,improving energy efficiency and sufficiency,promoting electrification,implementing photovoltaic-energy storage-direct current-flexibility(PEDF)buildings,decarbonizing heating systems,and developing new energy systems for rural areas.In addition,we discussed and recommended policy measures to enhance building service provisions within the framework of the ecological development concept and promote key technologies within the context of a low-carbon energy system transition.The findings of this study provide high-level recommendations for policymakers in the building and energy sectors and offer insights into technological perspectives and development targets for future research and engineering practice.
文摘Quality management in building curtain wall construction covers both the essence and scope,including material control and process control.It is crucial for safety,longevity,and energy efficiency.Although quality management models are diverse,they have their limitations.The paper also discusses key points such as quality issues,material and process compatibility,and node construction,along with various techniques and management methods to improve quality.It also highlights areas for further research and future directions.
文摘This paper will report on the development of a prototype of actively controlled facade module,which is capable of adapting its solar transmittance to changeable solar gains.Hence this new facade offers additional features with respect to the most popular currently used glass facades,which have fixed solar transmittance indeed.The novel technology is made possible by the creation of an additional 1.5-mm-thick sliding shielding liquid,which flows internally,in order to dynamically adapt the window’s solar transmittance.As compared with competitive technologies,this shielding system has low manufacturing costs,is durable,is completely reversible and always transparent,irrespective of its transmittance state.Specifically,the manufacture of a full-size window prototype and the engineering of the window was carried out;moreover,glass pane bending when subject to hydrostatic pressure was eventually assessed.All this information has been used to set up the industrial process needed for its manufacturing.
基金co-supported by National Key R&D Program of China(No.2022YFB4602003)Key Project of National Natural Science Foundation of China(No.12032018)+2 种基金Guangdong Basic and Applied Basic Research Foundation(No.2022A1515110489)National Natural Science Foundation of China-China Academy of General Technology Joint Fund for Basic Research(No.52375380)National Key Research and Development Program of China(No.2022YFB3402200)。
文摘A novel Additive Manufacturing(AM)-driven concurrent design strategy based on the beam characterization model considering strength constraints is proposed.The lattice topology,radius size,Building Orientation(BO),and structural yield strength can be simultaneously adjusted by integrating the overall process-structure-performance relationship of the AM process into the optimization.Specifically,the transverse isotropic material model is adopted to describe the material properties induced by the layer-by-layer manner of additive manufacturing.To bolster lattice strength performance,the stress constraints and ratio constraints of lattice struts are employed.The Tsai-Wu yield criterion is implemented to characterize the lattice strut's strength,while the P-norm method streamlines the handling of multiple constraints,minimizing computational overhead.Moreover,the gradient-based optimization model is established,where both the individual struts diameters and BO can be designed,and the buckling-prone spatial struts are strategically eliminated to improve the lattice strength further.Furthermore,several typical structures are optimized to verify the effectiveness of the proposed method.The optimized results are quite encouraging since the heterogeneous lattice structures with optimized BO obtained by the strength-based concurrent method show a remarkably improved performance compared to traditional designs.
基金supported by the National Natural Science Foundation of China(52078269 and 52325801).
文摘Substantially glazed facades are extensively used in contemporary high-rise buildings to achieve attractive architectural aesthetics.Inherent conflicts exist among architectural aesthetics,building energy consumption,and solar energy harvesting for glazed facades.In this study,we addressed these conflicts by introducing a new dynamic and vertical photovoltaic integrated building envelope(dvPVBE)that offers extraordinary flexibility with weather-responsive slat angles and blind positions,superior architectural aesthetics,and notable energy-saving potential.Three hierarchical control strategies were proposed for different scenarios of the dvPVBE:power generation priority(PGP),natural daylight priority(NDP),and energy-saving priority(ESP).Moreover,the PGP and ESP strategies were further analyzed in the simulation of a dvPVBE.An office room integrated with a dvPVBE was modeled using EnergyPlus.The influence of the dvPVBE in improving the building energy efficiency and corresponding optimal slat angles was investigated under the PGP and ESP control strategies.The results indicate that the application of dvPVBEs in Beijing can provide up to 131%of the annual energy demand of office rooms and significantly increase the annual net energy output by at least 226%compared with static photovoltaic(PV)blinds.The concept of this novel dvPVBE offers a viable approach by which the thermal load,daylight penetration,and energy generation can be effectively regulated.
基金National Key R&D Program of China of the 13th Five-Year Plan(No.2018YFD1100704)。
文摘To meet the challenge of mismatches between power supply and demand,modern buildings must schedule flexible energy loads in order to improve the efficiency of power grids.Furthermore,it is essential to understand the effectiveness of flexibility management strategies under different climate conditions and extreme weather events.Using both typical and extreme weather data from cities in five major climate zones of China,this study investigates the energy flexibility potential of an office building under three short-term HVAC management strategies in the context of different climates.The results show that the peak load flexibility and overall energy performance of the three short-term strategies were affected by the surrounding climate conditions.The peak load reduction rate of the pre-cooling and zone temperature reset strategies declined linearly as outdoor temperature increased.Under extreme climate conditions,the daily peak-load time was found to be over two hours earlier than under typical conditions,and the intensive solar radiation found in the extreme conditions can weaken the correlation between peak load reduction and outdoor temperature,risking the ability of a building’s HVAC system to maintain a comfortable indoor environment.
基金fellowship received from the Department of Science and Technology(DST)under a unique scheme,“Innovation in Science Pursuit for Inspired Research(INSPIRE),”under the file number 20190000871,during the present work。
文摘The present study investigates the influence of embedment depth of isolated footing supporting moment-resisting frame buildings through scaled-down tests.These experiments utilize scaled models representing different building aspect ratios and footing embedment depths.All the model tests are subjected to scaled-down input ground motions of different intensities and magnitudes.These model tests are performed in laminar shear containers through shake table testing.The results obtained for different cases of soil-foundation-structure systems and fixed-base conditions are expressed in terms of natural frequency,peak spectral acceleration,frequency response,lateral deformation,inter-storey drifts,and rocking of the foundation.The analysis reveals that the natural frequency of the coupled system on isolated footings diminishes by 27.52%–58.21%relative to fixed-base conditions,highlighting the significance of accounting for soil-foundation-structure interaction effects.Moreover,a notable increase of 52.97%in the natural frequency of the coupled system is observed as the embedment depth of the footing increases from 0.75 to 6.Additionally,the study demonstrates that the inter-storey drift of the 5-storey building remains well within acceptable limits under dense soil conditions.Consequently,within the parameter range explored in this research,the study concludes that soil-foundation-structure interaction effects are insignificant for low-rise buildings(H≤15 m)supported on isolated footings during seismic events.
基金supported by the National Key R&D Program of China(2023YFC3806202)the National Natural Science Foundation of China(52308093)+3 种基金the Natural Science Foundation of Hunan Province(2023JJ40154)the Science and Technology Innovation Leading Talent Program of Hunan Province(2023RC1042)the Natural Science Foundation of Changsha(kq2208032)the China Postdoctoral Science Foundation(2023M741132 and 2024T170263)。
文摘Vacuum glazing is highly regarded for its ability to transmit light while providing heat preservation,sound insulation,lightweight characteristics,and resistance to condensation.Scholars have made significant strides in the study of vacuum glazing through their notable efforts.This study systematically reviewed vacuum glazing and its composite structures,including material selection,fabrication techniques,research methods,and performance evaluation.This review initially presented fundamental techniques for preparing vacuum glazing,with a focus on edge seal and support pillar arrangements,and introduced common composite structures such as hybrid and tinted vacuum glazing.Furthermore,this review summarized the analytical,numerical,and experimental methodologies used to assess the thermal performance of vacuum glazing.This study also outlined heat transfer coefficients associated with various vacuum glazing structures,investigated the influence of different parameters on their heat transfer coefficients,and evaluated their potential for energy conservation across diverse climatic regions.Finally,the research delineated future trends in the advancement of vacuum glazing to provide guidance for both theoretical studies and practical applications in industry.This research serves as a valuable resource for both theoretical exploration and practical integration of vacuum glazing,facilitating its improvement and optimization to advance sustainable low-carbon building practices.
基金financially supported by the Collaborative Research Fund(C5018-20GF)of the Research Grant Council(RGC)of Hong Kong Special Administrative Regionthe Shenzhen Science and Technology Innovation Commission Grant(KCXST20221021111203007)。
文摘Pressure has been introduced into power systems owing to the intermittent and uncertain nature of renewable energy.As a result,energy resource aggregators are emerging in the electricity market to realize sustainable and economic advantages through distributed generation,energy storage,and demand response resources.However,resource aggregators face the challenge of dealing with the uncertainty of renewable energy generation and setting appropriate incentives to exploit substantial energy flexibility in the building sector.In this study,a risk-aware optimal dispatch strategy that integrates probabilistic renewable energy prediction and bi-level building flexibility engagements is proposed.A natural gradient boosting algorithm(NGBoost),which requires no prior knowledge of uncertain variables,was adopted to develop a probabilistic photovoltaic(PV)forecasting model.The lack of suitable flexibility incentives is addressed by a novel interactive flexibility engagement scheme that can take into account building users'willingness and optimize the building flexibility provision.The chance-constrained programming method was applied to manage the supply-demand balance of the resource aggregator and ensure risk-aware decision-making in power dispatch.The case study results show the strong economic and environmental performance of the proposed strategy.The proposed strategy leads to a win-win situation in which profit increases through a load reduction of 13% and a carbon emission reduction of 3% is achieved for different stakeholders,which also shows a trade-off between the economic benefits and the risk of supply shortage.
文摘In an environment where demand for housing is growing and the supply from public authorities is virtually non-existent,several mechanisms for housing production are emerging in the formal,semi-informal and informal construction sectors.The project owner wonders how much it costs to construct a building to an acceptable standard.Cost forecasting in general faces a number of difficulties,including a lack of available information during the preliminary phase of the project.As such,estimation becomes a crucial task involving great responsibility,which can lead to either more convincing results or chaotic situations.This study proposes a quick and effective method for estimating the cost of a single-storey F4 residential building.The modelling is done using multiple linear regression based on a statistical approach applied to twenty(20)projects that have already been completed.The project data are collected from design offices in the city of Brazzaville.The method expresses the cost of an F4 construction by certain project tasks,representing five(5)variables,three(3)of which are related to structural work and two(2)to finishing work,which are easy to determine.This approach,known as MECSO(Cost Estimation Model by Sub-structure),gives good results in all statistical tests carried out with reasonable confidence intervals.This method is very practical for engineering professionals working on the evaluation and control of construction costs.
基金Project(RGPIN-2019-05824)supported by the Start-up Fund of Universitéde Sherbrooke and Discovery Grants of Natural Sciences and Engineering Research Council of Canada(NSERC)。
文摘Ventilation is an effective solution for improving indoor air quality and reducing airborne transmission.Buildings need sufficient ventilation to maintain a low infection risk but also need to avoid an excessive ventilation rate,which may lead to high energy consumption.The Wells-Riley(WR)model is widely used to predict infection risk and control the ventilation rate.However,few studies compared the non-steady-state(NSS)and steady-state(SS)WR models that are used for ventilation control.To fill in this research gap,this study investigates the effects of the mechanical ventilation control strategies based on NSS/SS WR models on the required ventilation rates to prevent airborne transmission and related energy consumption.The modified NSS/SS WR models were proposed by considering many parameters that were ignored before,such as the initial quantum concentration.Based on the NSS/SS WR models,two new ventilation control strategies were proposed.A real building in Canada is used as the case study.The results indicate that under a high initial quantum concentration(e.g.,0.3 q/m^(3))and no protective measures,SS WR control underestimates the required ventilation rate.The ventilation energy consumption of NSS control is up to 2.5 times as high as that of the SS control.
基金Project(2018YFC0704500)supported by the National Science and Technology Major Project of China during the 13th Five-Year Plan Period。
文摘Accurate basic data are necessary to support performance-based design for achieving carbon peak and carbon neutral targets in the building sector.Meteorological parameters are the prerequisites of building thermal engineering design,heating ventilation and air conditioning design,and energy consumption simulations.Focusing on the key issues such as low spatial coverage and the lack of daily or higher time resolution data,daily and hourly models of the surface meteorological data and solar radiation were established and evaluated.Surface meteorological data and solar radiation data were generated for 1019 cities and towns in China from 1988 to 2017.The data were carefully compared,and the accuracy was proved to be high.All the meteorological parameters can be assessed in the building sector via a sharing platform.Then,country-level meteorological parameters were developed for energy-efficient building assessment in China,based on actual meteorological data in the present study.This set of meteorological parameters may facilitate engineering applications as well as allowing the updating and expansion of relevant building energy efficiency standards.The study was supported by the National Science and Technology Major Project of China during the 13th Five-Year Plan Period,named Fundamental parameters on building energy efficiency in China,comprising of 15 top-ranking universities and institutions in China.
基金Sponsored by the Key Project of National Natural Science Foundation of China(Grant No.51138004)the National Science and Technology Support Program(Grant No.2012BAJ10B02)
文摘Building buffer zone space is not only one of essential approaches for better mental quality of interior building space, but also an important factor that may influence interior thermal comfort and energy consumption. This study aims to analyze regulative advantages of buffer zone to the surrounding functional spaces. Based on a fieldwork test in a typical office building in cold climate zone in Beijing,China,the monitor data show interior physical performance in the Winter. The research selects two types of different buffer zones in the same building. One is a south-faced greenhouse which has large dimension with plenty of vegetation,and the other is a simple atrium in the middle of five floor building with mount of skylights. The factors and their influence to surrounding functional spaces and the whole building are found out from the comparisons of collected data by floor to floor monitor test on both buffer zones at the same time. The comparisons of two types of buffer zones conclude that the greenhouse is more effective to air quality regulation but not so clearly wellperformed to thermal buffering as expected due to the dominate active central heating in the Winter. This fieldwork test results for building performance can be helpful for both architects and engineers in the early phase of sustainable design.
基金Project(51178023)supported by the National Natural Science Foundation of China
文摘Multi-dimensional heat transfers modeling is crucial for building simulations of insulated buildings,which are widely used and have multi-dimensional heat transfers characteristics.For this work,state-model-reduction techniques were used to develop a reduced low-order model of multi-dimensional heat transfers.With hot box experiment of hollow block wall,heat flow relative errors between experiment and low-order model predication were less than 8% and the largest errors were less than 3%.Also,frequency responses of five typical walls,each with different thermal masses or insulation modes,the low-order model and the complete model showed that the low-order model results agree very well in the lower excitation frequency band with deviations appearing only at high frequency.Furthermore,low-order model was used on intersection thermal bridge of a floor slab and exterior wall.Results show that errors between the two models are very small.This low-order model could be coupled with most existing simulation software for different thermal mass envelope analyses to make up for differences between the multi-dimensional and one-dimensional models,simultaneously simplifying simulation calculations.
文摘This paper presents a study to optimize the heating energy costs in a residential building with varying electricity price signals based on an Economic Model Predictive Controller (EMPC). The investigated heating system consists of an air source heat pump (ASHP) incorporated with a hot water tank as active Thermal Energy Storage (TES), where two optimization problems are integrated together to optimize both the ASHP electricity consumption and the building heating consumption utilizing a heat dynamic model of the building. The results show that the proposed EMPC can save the energy cost by load shifting compared with some reference cases.
文摘Building defect is an issue in existing buildings that needs urgent tackling to prevent further problems. This study assessed the defects in concrete elements in residential buildings of 30 years and above in the Onitsha metropolis of Anambra State, Nigeria. Data collection instruments in the study include structured questionnaire, interviews, visual inspection/observations, archival records, recordings, photographs;and non-destructive testing of the concrete elements in an existing building in the study area. The population of this study constituted of the construction registered professionals and the existing buildings in study area. The sample for the study was based on the calculated sample size using Taro Yamani Formula. A total of 158 registered professionals were sampled from the population of 260. The questionnaires were purposively distributed to the registered professionals up to the required sample sizes of 158 and 129 questionnaires were properly filled and returned. The study used the SPSS and Microsoft Excel to analyze the data. The results were analyzed in percentages and figures using descriptive statistics and presented in the form of pie charts and tables. The finding of the study revealed that the causes and effects of structural defects on the concrete elements in existing buildings in the study area according to the rating are;exposed/corrosion of the embedded metals, faulty workmanship, overload and impacts, chemical attack, freeze-thaw deterioration, fire/heat, restraint to volume change. The visual observation revealed that the structural elements are characterized by heavy defects such as deep vertical, horizontal and diagonal cracks, exposed/ corrosion of the embedded metals, spalling of the concrete slabs. The existence of defects in the concrete members led to the low compressive strength of the concrete elements and the structural instability of the existing buildings as revealed by the non-destructive test. The non-destructive test result revealed that most of the tested concrete elements have low compressive strength value and such were remarked poor as they did not satisfy the assumed value. Essentially, the study concluded by recommending that regular monitoring, inspections and non-destructive testing of concrete elements should be conducted on existing aged and defected buildings to detect the structural stability of the buildings;and it is imperative to evacuate occupants from heavy structurally deteriorated and defected buildings since most of them have lost their residual design life span and ability to sustain imposed loads.
文摘The proliferation of multi-family residential building in Anambra State of Nigeria due to increasing demand without recourse to performance has broughtconcerns about the adequacy and sustainability of this housing type.This study therefore,assessed the adequacy and sustainability performance of multi-family residential buildings in urban areas of Anambra State.The study sampled the opinions of 384 households living in multi-family residential buildings through a questionnaire survey.We conducted data analysis based on 214 responses that were useful for analysis.The study found that internal and building component variables and supporting neigh-borhood variables were adequate,but the surrounding environment variables were inadequate based on Mean Score Index.However,based on Sustainability Performance Index,the occupant sperceived social sustainability performance of the buildings as satisfactory,while environmental and economic sustainability performance were perceived as fairly satisfactory.The Pearson correlation coefficient result further established that adequacy of internal and building component variables was significantly and positively related to the residents'perceived social sustainability performance.Adequacy of the surrounding environmental variables was also found to be positively and significantly related to the residents'perceived environmental sustainability performance,whereas adequacy of supporting neighborhood facilities was found to be negatively and significantly related to the residents’perceived economic sustainability performance.This sug-gested that investors and owners of multi-family residential buildings should direct more efforts towards improving the surrounding environment to supplements other facilities and increase the economic benefit of the renters or occupiers with increasing economic sustainability performance in terms of value for money.
文摘Riyadh city is the fastest growing city in Saudi Arabia. The rapid urban growth that happened recently in Riyadh was not based on the traditional urban planning principles, which have been established and applied for the city development process. The imported building regulations have created a new urban structures and street patterns. The contemporary urban form in Riyadh city is based mainly on traffic and economic consideration with the neglect of environmental dimensions. This research aims to examine the impacts of building regulations on the thermal performance of residential buildings in Riyadh city, with the ultimate goal of establishing planning guidelines that consider the environmental conditions of the city. The methodology adopted for achieving the aim of this study consists of two phases. First, the literature related to building regulations development in Riyadh, as of 2018, was reviewed. Second, buildings energy simulation was conducted to examine the thermal performance of the typical current status of residential building blocks in Riyadh city, and then several changes to building regulations were made to investigate their impacts on the thermal performance of buildings. The results showed that the impacts of Riyadh building regulations on the thermal performance of residential buildings differ across the evaluated cases. The ratio of building height to street width, urban block street orientation, and building orientation are the main factors affecting thermal performance of buildings within urban block. The study also concludes that adjusting the ratio of building height to the distance between buildings could have a significant impact in reducing cooling loads. This study will help policy makers, planners and designers to investigate the shortcoming in the current building regulations.
基金This manuscript has been authored by an author at Lawrence Berkeley National Laboratory under Contract No.DE-AC02-05CH11231 with the U.S.Department of Energy
文摘Decarbonization in operational residential buildings worldwide has become critical in achieving the carbon neutral target due to the growing household energy demand.To accelerate the pace of global carbon neutrality,this study explores the operational carbon change in global residential buildings through the generalized Divisia index method and decoupling analysis,considering the decarbonization levels of residential buildings at different scales.The results show that(1)most of the samples showed a decrease in the total emissions from 2000 to 2019.Except for China and the United States(US),the carbon emissions in global residential building operations decreased by 7.95 million tons of carbon dioxide(MtCO_(2))per year over the study period.Emissions per gross domestic product(GDP)was the most positive driver causing the decarbonization of residential buildings,while GDP was the most negative driver.(2)Carbon intensity was essential to achieving a strong decoupling of economic development and carbon emissions.The US almost consistently presented strong decoupling,while China showed weak decoupling over the last two decades.(3)The pace of decarbonization in global residential building operations is gradually slowing down.From 2000 to 2019,decarbonization from residential buildings across 30 countries was 2094.3 MtCO_(2),with a decarbonization efficiency of 3.4%.Overall,this study addresses gaps in evaluating global decarbonization from operational residential buildings and provides a reference for evaluating building decarbonization by other emitters.
