Pub Date : 2024-05-02DOI: 10.3389/fbuil.2024.1395448
Cesar Garcia, Alexis Iván Andrade Valle, Angel Alberto Silva Conde, Nestor Ulloa, Alireza Bahrami, K. Onyelowe, A. Ebid, Shadi Hanandeh
The mechanical characteristics of concrete are crucial factors in structural design standards especially in concrete technology. Employing reliable prediction models for concrete’s mechanical properties can reduce the number of necessary laboratory trials, checks and experiments to obtain valuable representative design data, thus saving both time and resources. Metakaolin (MK) is commonly utilized as a supplementary replacement for Portland cement in sustainable concrete production due to its technical and environmental benefits towards net-zero goals of the United Nations Sustainable Development Goals (UNSDGs). In this research work, 204 data entries from concrete mixes produced with the addition of metakaolin (MK) were collected and analyzed using eight (8) ensemble machine learning tools and one (1) symbolic regression technique. The application of multiple machine learning protocols such as the ensemble group and the symbolic regression techniques have not been presented in any previous research work on the modeling of splitting tensile strength of MK mixed concrete. The data was partitioned and applied according to standard conditions. Lastly, some selected performance evaluation indices were used to test the models’ accuracy in predicting the splitting strength (Fsp) of the studied MK-mixed concrete. At the end, results show that the k-nearest neighbor (KNN) outperformed the other techniques in the ensemble group with the following indices; SSE of 4% and 1%, MAE of 0.1 and 0.2 MPa, MSE of 0, RMSE of 0.1 and 0.2 MPa, Error of 0.04% and 0.04%, Accuracy of 0.96 and 0.96 and R2 of 0.98 and 0.98 for the training and validation models, respectively. This is followed closely by the support vector machine (SVM) with the following indices; SSE of 7% and 3%, MAE of 0.2 and 0.2 MPa, MSE of 0.0 and 0.1 MPa, RMSE of 0.2 and 0.3 MPa, Error of 0.05% and 0.06%, Accuracy of 0.95 and 0.94, and R2 of 0.96 and 0.95, for the training and validation models, respectively. The third model in the superiority rank is the CN2 with the following performance indices; SSE of 15% and 4%, MAE of 0.2 and 0.2 MPa, MSE of 0.1 and 0.1 MPa, RMSE of 0.3 and 0.3 MPa, Error of 0.08% and 0.07%, Accuracy of 0.92 and 0.93 and R2 of 0.92 and 0.93, for the training and validation models, respectively. These models outperformed the models utilized on the MK-mixed concrete found in the literature, therefore are the better decisive modes for the prediction of the splitting strength (Fsp) of the studied MK-mixed concrete with 204 mix data entries. Conversely, the NB and SGD produced unacceptable model performances, however, this is true for the modeled database collected for the MK-mixed Fsp. The RSM model also produced superior performance with an accuracy of over 95% and adequate precision of more than 27. Overall, the KNN, SVM, CN2 and RSM have shown to possess the potential to predict the MK-mixed Fsp for structural concrete designs and production.
{"title":"Predicting the impact of adding metakaolin on the splitting strength of concrete using ensemble ML classification and symbolic regression techniques –a comparative study","authors":"Cesar Garcia, Alexis Iván Andrade Valle, Angel Alberto Silva Conde, Nestor Ulloa, Alireza Bahrami, K. Onyelowe, A. Ebid, Shadi Hanandeh","doi":"10.3389/fbuil.2024.1395448","DOIUrl":"https://doi.org/10.3389/fbuil.2024.1395448","url":null,"abstract":"The mechanical characteristics of concrete are crucial factors in structural design standards especially in concrete technology. Employing reliable prediction models for concrete’s mechanical properties can reduce the number of necessary laboratory trials, checks and experiments to obtain valuable representative design data, thus saving both time and resources. Metakaolin (MK) is commonly utilized as a supplementary replacement for Portland cement in sustainable concrete production due to its technical and environmental benefits towards net-zero goals of the United Nations Sustainable Development Goals (UNSDGs). In this research work, 204 data entries from concrete mixes produced with the addition of metakaolin (MK) were collected and analyzed using eight (8) ensemble machine learning tools and one (1) symbolic regression technique. The application of multiple machine learning protocols such as the ensemble group and the symbolic regression techniques have not been presented in any previous research work on the modeling of splitting tensile strength of MK mixed concrete. The data was partitioned and applied according to standard conditions. Lastly, some selected performance evaluation indices were used to test the models’ accuracy in predicting the splitting strength (Fsp) of the studied MK-mixed concrete. At the end, results show that the k-nearest neighbor (KNN) outperformed the other techniques in the ensemble group with the following indices; SSE of 4% and 1%, MAE of 0.1 and 0.2 MPa, MSE of 0, RMSE of 0.1 and 0.2 MPa, Error of 0.04% and 0.04%, Accuracy of 0.96 and 0.96 and R2 of 0.98 and 0.98 for the training and validation models, respectively. This is followed closely by the support vector machine (SVM) with the following indices; SSE of 7% and 3%, MAE of 0.2 and 0.2 MPa, MSE of 0.0 and 0.1 MPa, RMSE of 0.2 and 0.3 MPa, Error of 0.05% and 0.06%, Accuracy of 0.95 and 0.94, and R2 of 0.96 and 0.95, for the training and validation models, respectively. The third model in the superiority rank is the CN2 with the following performance indices; SSE of 15% and 4%, MAE of 0.2 and 0.2 MPa, MSE of 0.1 and 0.1 MPa, RMSE of 0.3 and 0.3 MPa, Error of 0.08% and 0.07%, Accuracy of 0.92 and 0.93 and R2 of 0.92 and 0.93, for the training and validation models, respectively. These models outperformed the models utilized on the MK-mixed concrete found in the literature, therefore are the better decisive modes for the prediction of the splitting strength (Fsp) of the studied MK-mixed concrete with 204 mix data entries. Conversely, the NB and SGD produced unacceptable model performances, however, this is true for the modeled database collected for the MK-mixed Fsp. The RSM model also produced superior performance with an accuracy of over 95% and adequate precision of more than 27. Overall, the KNN, SVM, CN2 and RSM have shown to possess the potential to predict the MK-mixed Fsp for structural concrete designs and production.","PeriodicalId":505606,"journal":{"name":"Frontiers in Built Environment","volume":"12 16","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141018712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-01DOI: 10.3389/fbuil.2024.1280978
Pablo Agüero-Barrantes, Alexandra Hain
To address the shortcomings of traditional prestressed concrete girders, a new hybrid beam element, the Hybrid Deck Bulb Tee (HDBT) is proposed. The HDBT utilizes staged fabrication. First, the bottom flange is cast with Ultra-high Performance Concrete (UHPC) and prestressed prior to casting the web and top flange with High-Performance Concrete (HPC). The purpose of this study is to analytically evaluate the structural performance of HDBT beams for bridge structures. Multiple HDBT bridges were designed following the state-of-the-art criteria in regard to UHPC bridge design. The performance was evaluated using the following criteria: 1) the deflections under live load and dead load, 2) design checks for temporary stresses before losses, 3) stresses at serviceability limit states after losses, and 4) demand-to-capacity ratios under the American Association of State Highway and Transportation Officials (AASHTO) Strength I load combination. To obtain more refined results for the serviceability limit state, the bridges were modeled using a commercial finite element software. The model captured the time dependent material properties such as strength gain, creep, and shrinkage, as well as the stages of fabrication. The analysis demonstrates that the innovative design and fabrication processes of HDBTs are capable of resolving the current limitations of prestressed concrete elements.
{"title":"Numerical evaluation of Hybrid Deck Bulb Tee (HDBT) as a solution to improve durability of single-span bridges","authors":"Pablo Agüero-Barrantes, Alexandra Hain","doi":"10.3389/fbuil.2024.1280978","DOIUrl":"https://doi.org/10.3389/fbuil.2024.1280978","url":null,"abstract":"To address the shortcomings of traditional prestressed concrete girders, a new hybrid beam element, the Hybrid Deck Bulb Tee (HDBT) is proposed. The HDBT utilizes staged fabrication. First, the bottom flange is cast with Ultra-high Performance Concrete (UHPC) and prestressed prior to casting the web and top flange with High-Performance Concrete (HPC). The purpose of this study is to analytically evaluate the structural performance of HDBT beams for bridge structures. Multiple HDBT bridges were designed following the state-of-the-art criteria in regard to UHPC bridge design. The performance was evaluated using the following criteria: 1) the deflections under live load and dead load, 2) design checks for temporary stresses before losses, 3) stresses at serviceability limit states after losses, and 4) demand-to-capacity ratios under the American Association of State Highway and Transportation Officials (AASHTO) Strength I load combination. To obtain more refined results for the serviceability limit state, the bridges were modeled using a commercial finite element software. The model captured the time dependent material properties such as strength gain, creep, and shrinkage, as well as the stages of fabrication. The analysis demonstrates that the innovative design and fabrication processes of HDBTs are capable of resolving the current limitations of prestressed concrete elements.","PeriodicalId":505606,"journal":{"name":"Frontiers in Built Environment","volume":"21 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141023027","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-01DOI: 10.3389/fbuil.2024.1385680
G. La Verde, Gaetano Gagliardo, Fabrizio Ambrosino, Mariagabriella Pugliese
Introduction: Risk assessment of exposure to indoor pollutants plays an increasingly important role in human protection, and one of the main sources of indoor pollutants is building materials (BMs). In addition, production processes, including those related to BMs, are also involved in economic transition: the use of by-products from other industrial sectors as raw materials for the production processes in compliance with environmental sustainability is evaluated.Methods: In this work, we evaluate not only the radiation protection of BMs but also the possibility of adopting the circular economy principles. The two main objectives of this study were 1) radiometric characterization and calculation of Index I of pozzolan from Altavilla Irpina (Avellino) in Italy, used as a natural igneous additive for concrete, using gamma spectroscopy, and 2) comparison of different methodologies for calculating the annual effective dose of BMs (CEN/TR 17113:2017, RESRAD-BUILD software, and a previously developed experimental method). The same approach was extended to the possibility of reusing fly ash—a naturally occurring radioactive material (NORM) by-product of coal combustion in thermal power plants—for the production of concrete.Results and Discussion: The study aligns with the principles linked to the circular economy to extend the life cycle of materials by reducing the need for natural resources, suggesting a possible positive compromise between radioprotection and preservation of environmental heritage.
{"title":"Implementation of dose calculation methods for NORM by-products in building materials in the circular economy framework","authors":"G. La Verde, Gaetano Gagliardo, Fabrizio Ambrosino, Mariagabriella Pugliese","doi":"10.3389/fbuil.2024.1385680","DOIUrl":"https://doi.org/10.3389/fbuil.2024.1385680","url":null,"abstract":"Introduction: Risk assessment of exposure to indoor pollutants plays an increasingly important role in human protection, and one of the main sources of indoor pollutants is building materials (BMs). In addition, production processes, including those related to BMs, are also involved in economic transition: the use of by-products from other industrial sectors as raw materials for the production processes in compliance with environmental sustainability is evaluated.Methods: In this work, we evaluate not only the radiation protection of BMs but also the possibility of adopting the circular economy principles. The two main objectives of this study were 1) radiometric characterization and calculation of Index I of pozzolan from Altavilla Irpina (Avellino) in Italy, used as a natural igneous additive for concrete, using gamma spectroscopy, and 2) comparison of different methodologies for calculating the annual effective dose of BMs (CEN/TR 17113:2017, RESRAD-BUILD software, and a previously developed experimental method). The same approach was extended to the possibility of reusing fly ash—a naturally occurring radioactive material (NORM) by-product of coal combustion in thermal power plants—for the production of concrete.Results and Discussion: The study aligns with the principles linked to the circular economy to extend the life cycle of materials by reducing the need for natural resources, suggesting a possible positive compromise between radioprotection and preservation of environmental heritage.","PeriodicalId":505606,"journal":{"name":"Frontiers in Built Environment","volume":"74 11","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141035260","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-28DOI: 10.3389/fbuil.2024.1324954
Muhammad Khan, Komal Bilal, Gohar Alam
This study aimed to determine the effect of technology on the upgradation of slums in Islamabad, along with the moderating role of upstream influences between them. With this concern, the researcher used a quantitative research design, and to accumulate the data, a closed-ended survey questionnaire was chosen. The sample size considered in this research was 293 participants belonging to the urban planning sector of Islamabad. To evaluate the data and hypothesized model, structural equation modeling (SEM) was used. It was also revealed that upward influences moderated the association between technology and slum upgradation significantly, particularly regarding governance, religion, and gender roles. However, this research is limited to Islamabad only; therefore, the implications of this study cannot be generalized. Consequently, it has been recommended that upward influences based on crime and mafia, along with governance, should be controlled to upgrade Islamabad-based slums.
{"title":"Impact of technology on upgrading slums and the moderating role of upstream influences: a contemporary approach to urban planning","authors":"Muhammad Khan, Komal Bilal, Gohar Alam","doi":"10.3389/fbuil.2024.1324954","DOIUrl":"https://doi.org/10.3389/fbuil.2024.1324954","url":null,"abstract":"This study aimed to determine the effect of technology on the upgradation of slums in Islamabad, along with the moderating role of upstream influences between them. With this concern, the researcher used a quantitative research design, and to accumulate the data, a closed-ended survey questionnaire was chosen. The sample size considered in this research was 293 participants belonging to the urban planning sector of Islamabad. To evaluate the data and hypothesized model, structural equation modeling (SEM) was used. It was also revealed that upward influences moderated the association between technology and slum upgradation significantly, particularly regarding governance, religion, and gender roles. However, this research is limited to Islamabad only; therefore, the implications of this study cannot be generalized. Consequently, it has been recommended that upward influences based on crime and mafia, along with governance, should be controlled to upgrade Islamabad-based slums.","PeriodicalId":505606,"journal":{"name":"Frontiers in Built Environment","volume":"19 12","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140371953","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-27DOI: 10.3389/fbuil.2024.1372288
A. Lešinskis, Uldis Strauts, Martins Metals, R. Millers, Viktors Afoņičevs
Society needs long-term sustainability and healthy building projects, and indoor air quality assurance engineering systems play a pivotal role in the energy performance of buildings. Therefore, when designing heating, ventilation, and air conditioning systems, it is crucial to make the most technically sound decisions in terms of energy consumption and assess their impact on the building’s energy performance. This article delves into the design of ventilation and air conditioning systems, presenting a method for evaluating their performance. The foundation of project development is an agreement on the design criteria, which are developed based on a preliminary analysis of the building concept. This agreement ensures cohesive collaboration among all stakeholders: the client, the architect, the system designer, the contractor, and ultimately the personnel responsible for commissioning, operating, and maintaining the systems post-construction. We suggest conducting a comprehensive analysis of the processes occurring within the space without initially linking them to room air exchange. From this analysis, we derive the angular coefficient for the direction of the air condition change on both a psychrometric chart and a Mollier diagram. The process line on the psychrometric chart provides insights into how the performance factor of the air distribution system will influence the desired supply air parameters. We can then evaluate how significantly the gap between the supply air and the exhaust air parameters expands if the room’s air exchange volume is reduced for budgetary reasons. The article showcases this design methodology using a simplified case study.
{"title":"Ventilation and air conditioning design approach based on ASHRAE psychrometric chart and Mollier diagram","authors":"A. Lešinskis, Uldis Strauts, Martins Metals, R. Millers, Viktors Afoņičevs","doi":"10.3389/fbuil.2024.1372288","DOIUrl":"https://doi.org/10.3389/fbuil.2024.1372288","url":null,"abstract":"Society needs long-term sustainability and healthy building projects, and indoor air quality assurance engineering systems play a pivotal role in the energy performance of buildings. Therefore, when designing heating, ventilation, and air conditioning systems, it is crucial to make the most technically sound decisions in terms of energy consumption and assess their impact on the building’s energy performance. This article delves into the design of ventilation and air conditioning systems, presenting a method for evaluating their performance. The foundation of project development is an agreement on the design criteria, which are developed based on a preliminary analysis of the building concept. This agreement ensures cohesive collaboration among all stakeholders: the client, the architect, the system designer, the contractor, and ultimately the personnel responsible for commissioning, operating, and maintaining the systems post-construction. We suggest conducting a comprehensive analysis of the processes occurring within the space without initially linking them to room air exchange. From this analysis, we derive the angular coefficient for the direction of the air condition change on both a psychrometric chart and a Mollier diagram. The process line on the psychrometric chart provides insights into how the performance factor of the air distribution system will influence the desired supply air parameters. We can then evaluate how significantly the gap between the supply air and the exhaust air parameters expands if the room’s air exchange volume is reduced for budgetary reasons. The article showcases this design methodology using a simplified case study.","PeriodicalId":505606,"journal":{"name":"Frontiers in Built Environment","volume":"30 21","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140373719","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-25DOI: 10.3389/fbuil.2024.1389576
Hai-zuo Zhou, Fujian Ma, Xiaoxuan Yu, Gang Zheng
The fragility curve expresses the probability that an asset exceeds some serviceability state for a given level of environmental perturbation or other loadings. It is an important component in the quantitative risk analysis and resilience evaluation of infrastructure exposed to natural hazards. Incidences of over-settlement of embankments are increasingly reported due to more intense and longer-duration rainfall events. This paper develops fragility curves for the rainfall-induced embankment settlement. For this purpose, an embankment incorporating enhanced seepage and displacement analysis within unsaturated soil conditions is modelled based on a reported case history. A Monte Carlo simulation is used for rainfall infiltration and embankment deformation analysis under various rainfall scenarios. Probability values are obtained to achieve three levels of damage states in terms of road embankment settlement. The parametric analysis produces the exceedance probability curves for various rainfall intensities, saturated permeabilities and embankment slope angles. This work offers an efficient tool for assessing fragility to rainfall-induced excessive settlement of embankments.
{"title":"Fragility assessment for the rainfall-induced embankments on silty soils","authors":"Hai-zuo Zhou, Fujian Ma, Xiaoxuan Yu, Gang Zheng","doi":"10.3389/fbuil.2024.1389576","DOIUrl":"https://doi.org/10.3389/fbuil.2024.1389576","url":null,"abstract":"The fragility curve expresses the probability that an asset exceeds some serviceability state for a given level of environmental perturbation or other loadings. It is an important component in the quantitative risk analysis and resilience evaluation of infrastructure exposed to natural hazards. Incidences of over-settlement of embankments are increasingly reported due to more intense and longer-duration rainfall events. This paper develops fragility curves for the rainfall-induced embankment settlement. For this purpose, an embankment incorporating enhanced seepage and displacement analysis within unsaturated soil conditions is modelled based on a reported case history. A Monte Carlo simulation is used for rainfall infiltration and embankment deformation analysis under various rainfall scenarios. Probability values are obtained to achieve three levels of damage states in terms of road embankment settlement. The parametric analysis produces the exceedance probability curves for various rainfall intensities, saturated permeabilities and embankment slope angles. This work offers an efficient tool for assessing fragility to rainfall-induced excessive settlement of embankments.","PeriodicalId":505606,"journal":{"name":"Frontiers in Built Environment","volume":" 18","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140381827","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-02-29DOI: 10.3389/fbuil.2024.1363370
Ali Alhussain, José P. Duarte, Nathan C. Brown
With the growing global need for housing and infrastructure, 3D concrete printing (3DCP) has emerged as an innovative construction method offering several potential benefits including design flexibility, speed, and sustainability. However, enhancing the reliability of 3DCP involves managing a variety of parameters that influence various aspects of the 3D printed structure. Process parameters like nozzle velocity, nozzle diameter, nozzle height, and material flow velocity have a major impact on the structural stability and filament shape. This project aimed to develop fast and accurate data-driven models for predicting and classifying filament shape based on process parameters. A print experiment systematically varied process parameters across 144 samples. The resulting filament geometry (width, height, contact width) was measured and classified by quality. Models were trained on this data to predict filament width, contact width, filament height, and classify filaments. These models can be utilized with any buildable material - a material with a high enough yield stress to bear the weight of upper layers without significant deformation. This condition does not restrict this study’s scope as it is a prerequisite for all 3DCP applications. The models’ robustness and generalizability were confirmed through validation on literature data across various printable materials and setups. These data-driven models can aid in optimizing parameters, generating variable width filaments, and printing non-planar layers. By linking print inputs to filament outputs, this comprehensive modeling approach advances 3DCP research for more reliable and versatile concrete printing.
{"title":"Developing a data-driven filament shape prediction model for 3D concrete printing","authors":"Ali Alhussain, José P. Duarte, Nathan C. Brown","doi":"10.3389/fbuil.2024.1363370","DOIUrl":"https://doi.org/10.3389/fbuil.2024.1363370","url":null,"abstract":"With the growing global need for housing and infrastructure, 3D concrete printing (3DCP) has emerged as an innovative construction method offering several potential benefits including design flexibility, speed, and sustainability. However, enhancing the reliability of 3DCP involves managing a variety of parameters that influence various aspects of the 3D printed structure. Process parameters like nozzle velocity, nozzle diameter, nozzle height, and material flow velocity have a major impact on the structural stability and filament shape. This project aimed to develop fast and accurate data-driven models for predicting and classifying filament shape based on process parameters. A print experiment systematically varied process parameters across 144 samples. The resulting filament geometry (width, height, contact width) was measured and classified by quality. Models were trained on this data to predict filament width, contact width, filament height, and classify filaments. These models can be utilized with any buildable material - a material with a high enough yield stress to bear the weight of upper layers without significant deformation. This condition does not restrict this study’s scope as it is a prerequisite for all 3DCP applications. The models’ robustness and generalizability were confirmed through validation on literature data across various printable materials and setups. These data-driven models can aid in optimizing parameters, generating variable width filaments, and printing non-planar layers. By linking print inputs to filament outputs, this comprehensive modeling approach advances 3DCP research for more reliable and versatile concrete printing.","PeriodicalId":505606,"journal":{"name":"Frontiers in Built Environment","volume":"18 46","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140409506","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-02-29DOI: 10.3389/fbuil.2024.1301049
Qahtan Al-Shami, Jiankun Huang, M. Amran, Saleh Mugahed, Ayed Eid Alluqmani, Mohammed Al-Haaj, Yaser Gamil, Hakim S. Abdelgader
This paper aims to elucidate the clear visibility of attenuating seismic waves (SWs) with forest trees as natural metamaterials known as forest metamaterials (FMs) arranged in a periodic pattern around the protected area. In analyzing the changeability of the FM models, five distinct cases of “metawall” configurations were considered. Numerical simulations were conducted to study the characteristics of bandgaps (BGs) and vibration modes for each model. The finite element method (FEM) was used to illustrate the generation of BGs in low frequency ranges. The commercial finite element code COMSOL Multiphysics 5.4a was adopted to carry out the numerical analysis, utilizing the sound cone method and the strain energy method. Wide BGs were generated for the Bragg scattering BGs and local resonance BGs owing to the gradual variations in tree height and the addition of a vertical load in the form of mass to simulate the tree foliage. The results were promising and confirmed the applicability of FEM based on the parametric design language ANSYS 17.2 software to apply the boundary conditions of the proposed models at frequencies below 100 Hz. The effects of the mechanical properties of the six layers of soil and the geometric parameters of FMs were studied intensively. Unit cell layouts and an engineered configuration for arranging FMs based on periodic theory to achieve significant results in controlling ground vibrations, which are valuable for protecting a large number of structures or an entire city, are recommended. Prior to construction, protecting a region and exerting control over FM characteristics are advantageous. The results exhibited the effect of the ‘trees’ upper portion (e.g., leaves, crown, and lateral bulky branches) and the gradual change in tree height on the width and position of BGs, which refers to the attenuation mechanism. Low frequency ranges of less than 100 Hz were particularly well suited for attenuating SWs with FMs. However, an engineering method for a safe city construction should be proposed on the basis of the arrangement of urban trees to allow for the shielding of SWs in specific frequency ranges.
{"title":"Efficient numerical simulations on the forest barrier for seismic wave attenuation: engineering safe constructions","authors":"Qahtan Al-Shami, Jiankun Huang, M. Amran, Saleh Mugahed, Ayed Eid Alluqmani, Mohammed Al-Haaj, Yaser Gamil, Hakim S. Abdelgader","doi":"10.3389/fbuil.2024.1301049","DOIUrl":"https://doi.org/10.3389/fbuil.2024.1301049","url":null,"abstract":"This paper aims to elucidate the clear visibility of attenuating seismic waves (SWs) with forest trees as natural metamaterials known as forest metamaterials (FMs) arranged in a periodic pattern around the protected area. In analyzing the changeability of the FM models, five distinct cases of “metawall” configurations were considered. Numerical simulations were conducted to study the characteristics of bandgaps (BGs) and vibration modes for each model. The finite element method (FEM) was used to illustrate the generation of BGs in low frequency ranges. The commercial finite element code COMSOL Multiphysics 5.4a was adopted to carry out the numerical analysis, utilizing the sound cone method and the strain energy method. Wide BGs were generated for the Bragg scattering BGs and local resonance BGs owing to the gradual variations in tree height and the addition of a vertical load in the form of mass to simulate the tree foliage. The results were promising and confirmed the applicability of FEM based on the parametric design language ANSYS 17.2 software to apply the boundary conditions of the proposed models at frequencies below 100 Hz. The effects of the mechanical properties of the six layers of soil and the geometric parameters of FMs were studied intensively. Unit cell layouts and an engineered configuration for arranging FMs based on periodic theory to achieve significant results in controlling ground vibrations, which are valuable for protecting a large number of structures or an entire city, are recommended. Prior to construction, protecting a region and exerting control over FM characteristics are advantageous. The results exhibited the effect of the ‘trees’ upper portion (e.g., leaves, crown, and lateral bulky branches) and the gradual change in tree height on the width and position of BGs, which refers to the attenuation mechanism. Low frequency ranges of less than 100 Hz were particularly well suited for attenuating SWs with FMs. However, an engineering method for a safe city construction should be proposed on the basis of the arrangement of urban trees to allow for the shielding of SWs in specific frequency ranges.","PeriodicalId":505606,"journal":{"name":"Frontiers in Built Environment","volume":"20 14","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140413045","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-02-26DOI: 10.3389/fbuil.2024.1309621
Nathan Hays, Lidia Badarnah, Anuj Jain
The built environment faces significant challenges in managing energy demands amidst rising temperatures and increasing concerns linked to climate change. Meeting carbon emissions targets and resource management goals necessitates urgent innovation in more energy-efficient cooling solutions. Nature offers a large database of adaptive and efficient thermal solutions that can be harnessed through biomimetic methods in building design and systems. Emerging biomimetic and computational approaches hold promise in facilitating practical application efforts. This paper investigates the translation of morphological features from elephant skin to building facades, optimizing their inherent cooling capabilities through computational design using evolutionary algorithms. Through this exploration, we propose a set of generalized evolutionary principles, offering a foundational framework for the development of textured facade tiles with the aim of mitigating heat gain from solar radiation. This study provides an in-depth analysis of how assembly, texture depth, and orientation impact thermal performance, enabling the design of more effective passive cooling systems through an understanding of the relationship between morphological variations in textured surfaces and environmental performance. Future research may involve studying natural convection dynamics, optimizing capillary networks, evaluating materials for water adhesion and cleaning, assessing impacts on biological growth, and exploring biodiversity integration within textured facade panels.
{"title":"Biomimetic design of building facades: an evolutionary-based computational approach inspired by elephant skin for cooling in hot and humid climates","authors":"Nathan Hays, Lidia Badarnah, Anuj Jain","doi":"10.3389/fbuil.2024.1309621","DOIUrl":"https://doi.org/10.3389/fbuil.2024.1309621","url":null,"abstract":"The built environment faces significant challenges in managing energy demands amidst rising temperatures and increasing concerns linked to climate change. Meeting carbon emissions targets and resource management goals necessitates urgent innovation in more energy-efficient cooling solutions. Nature offers a large database of adaptive and efficient thermal solutions that can be harnessed through biomimetic methods in building design and systems. Emerging biomimetic and computational approaches hold promise in facilitating practical application efforts. This paper investigates the translation of morphological features from elephant skin to building facades, optimizing their inherent cooling capabilities through computational design using evolutionary algorithms. Through this exploration, we propose a set of generalized evolutionary principles, offering a foundational framework for the development of textured facade tiles with the aim of mitigating heat gain from solar radiation. This study provides an in-depth analysis of how assembly, texture depth, and orientation impact thermal performance, enabling the design of more effective passive cooling systems through an understanding of the relationship between morphological variations in textured surfaces and environmental performance. Future research may involve studying natural convection dynamics, optimizing capillary networks, evaluating materials for water adhesion and cleaning, assessing impacts on biological growth, and exploring biodiversity integration within textured facade panels.","PeriodicalId":505606,"journal":{"name":"Frontiers in Built Environment","volume":"24 25","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140429945","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-02-22DOI: 10.3389/fbuil.2024.1273311
Babak Salarieh, A. Salman
The projected increase in sea surface temperature due to climate change is expected to substantially intensify future hurricanes. Wooden light-frame residential buildings are particularly vulnerable to hurricane damage, and their risk is expected to increase due to heightened exposure and intensifying hurricanes. Therefore, adaptation strategies need to be planned to reduce damage to such buildings while considering the impact of climate change on hurricanes. This study investigates the effectiveness of various climate change adaptation strategies for coastal wood-frame single-story residential buildings and demonstrates how these strategies can be planned. The study considers the four Representative Concentration Pathways (RCPs) proposed by the IPCC to investigate the impact of climate change on wind hazard and losses. Additionally, three locations in the coastal United States of varying sizes, exposure, and hurricane hazard levels are considered: Harris County, Texas; Mobile County, Alabama; and Miami-Dade County, Florida. The results show that the increase in wind speeds and losses will be non-linear with time. All considered adaptation strategies decreased losses, with some able to completely counter the increasing losses even under high emission scenarios. Investigating the effectiveness of adaptive measures can guide stakeholders in allocating funds and efforts for hurricane risk management and enhancing community resilience.
{"title":"Regional climate change adaptation planning: a case study on single-story wooden-frame residential buildings vulnerable to hurricane winds in selected US coastal locations","authors":"Babak Salarieh, A. Salman","doi":"10.3389/fbuil.2024.1273311","DOIUrl":"https://doi.org/10.3389/fbuil.2024.1273311","url":null,"abstract":"The projected increase in sea surface temperature due to climate change is expected to substantially intensify future hurricanes. Wooden light-frame residential buildings are particularly vulnerable to hurricane damage, and their risk is expected to increase due to heightened exposure and intensifying hurricanes. Therefore, adaptation strategies need to be planned to reduce damage to such buildings while considering the impact of climate change on hurricanes. This study investigates the effectiveness of various climate change adaptation strategies for coastal wood-frame single-story residential buildings and demonstrates how these strategies can be planned. The study considers the four Representative Concentration Pathways (RCPs) proposed by the IPCC to investigate the impact of climate change on wind hazard and losses. Additionally, three locations in the coastal United States of varying sizes, exposure, and hurricane hazard levels are considered: Harris County, Texas; Mobile County, Alabama; and Miami-Dade County, Florida. The results show that the increase in wind speeds and losses will be non-linear with time. All considered adaptation strategies decreased losses, with some able to completely counter the increasing losses even under high emission scenarios. Investigating the effectiveness of adaptive measures can guide stakeholders in allocating funds and efforts for hurricane risk management and enhancing community resilience.","PeriodicalId":505606,"journal":{"name":"Frontiers in Built Environment","volume":"8 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140441185","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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