Pub Date : 2023-12-25DOI: 10.3390/buildings14010064
Hao Wu, Ge Wang, Mingliang Li, Yue Zhao, Jun Li, Dingding Han, Pengfei Li
To assess the medium-term performance of porous asphalt pavement during service and its influence on tire/pavement noise level, a seven-year continuous observation and data analysis study was conducted. Key performance indicators were measured and calculated by using automated pavement technology testing equipment. The noise levels were tested by using the on-board sound intensity (OBSI) method on three types of porous asphalt pavements (PUC-10, PAC-13, and PUC-10 + PAC-13) and one dense thin layer course (DTC) for comparison. The findings indicated that the Damage Rate (DR) and Surface Friction Coefficient (SFC) of porous asphalt pavements diminished greatly over time, while the International Roughness Index (IRI) and Rut Depth (RD) remained relatively stable. The two-layer porous asphalt pavement showed the largest noise reduction over the medium-term. Compared to DTC, the OBSI noise levels of these structures were lower by 2.09 dB, 1.53 dB, and 2.88 dB, respectively. The OBSI was found to be closely correlated with the SFC, IRI, test speed, lane, and pavement type. The RD had a notable effect on the OBSI in PUC-10 pavements. In PUC-10 + PAC-13 pavements, a significant linear relationship was observed between the OBSI and SFC. This is mainly because of the polishing of the coarse aggregates, which leads to micro-texture reduction, high frequency noise increase, and SFC decrease. This study makes a valuable contribution to understanding the laws of porous asphalt pavement performance changes and the relationship between tire/pavement noise and pavement characteristics.
{"title":"Investigation of Medium-Term Performance of Porous Asphalt and Its Impacts on Tire/Pavement Noise","authors":"Hao Wu, Ge Wang, Mingliang Li, Yue Zhao, Jun Li, Dingding Han, Pengfei Li","doi":"10.3390/buildings14010064","DOIUrl":"https://doi.org/10.3390/buildings14010064","url":null,"abstract":"To assess the medium-term performance of porous asphalt pavement during service and its influence on tire/pavement noise level, a seven-year continuous observation and data analysis study was conducted. Key performance indicators were measured and calculated by using automated pavement technology testing equipment. The noise levels were tested by using the on-board sound intensity (OBSI) method on three types of porous asphalt pavements (PUC-10, PAC-13, and PUC-10 + PAC-13) and one dense thin layer course (DTC) for comparison. The findings indicated that the Damage Rate (DR) and Surface Friction Coefficient (SFC) of porous asphalt pavements diminished greatly over time, while the International Roughness Index (IRI) and Rut Depth (RD) remained relatively stable. The two-layer porous asphalt pavement showed the largest noise reduction over the medium-term. Compared to DTC, the OBSI noise levels of these structures were lower by 2.09 dB, 1.53 dB, and 2.88 dB, respectively. The OBSI was found to be closely correlated with the SFC, IRI, test speed, lane, and pavement type. The RD had a notable effect on the OBSI in PUC-10 pavements. In PUC-10 + PAC-13 pavements, a significant linear relationship was observed between the OBSI and SFC. This is mainly because of the polishing of the coarse aggregates, which leads to micro-texture reduction, high frequency noise increase, and SFC decrease. This study makes a valuable contribution to understanding the laws of porous asphalt pavement performance changes and the relationship between tire/pavement noise and pavement characteristics.","PeriodicalId":48546,"journal":{"name":"Buildings","volume":"11 5","pages":""},"PeriodicalIF":3.8,"publicationDate":"2023-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139158044","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-25DOI: 10.3390/buildings14010063
M. R. Cabral, Pierre Blanchet
Material selection in buildings profoundly affects project success, encompassing durability, maintenance, customer satisfaction, production systems, lifecycle, usage, environment, and costs. Yet, there is a need for further research on indicators for choosing materials in prefabricated buildings. Therefore, this study’s main objective was to identify the indicators (criteria and sub-criteria) for selecting materials for prefabricated wooden construction and, subsequently, categorize these criteria and sub-criteria based on the perspective of industry professionals. To achieve this goal, three phases were carried out. First, a literature review was conducted to identify potential criteria for choosing structural and envelope materials in wooden prefabricated buildings. Second, a pilot survey was conducted in Canada and the United States to classify the priority order of the criteria obtained from the literature based on professionals’ opinions. Finally, Monte Carlo simulations were conducted with different iterations (1000, 10,000, and 100,000) using the data obtained from the previous phase to improve decision-making and classification processes. For the indicators to select materials, the literature review identified seven main criteria: performance properties, green materials, energy efficiency, circular economy, site conditions and material logistics, standards, and social impact. These criteria contained a total of 25 sub-criteria. The pilot survey data analysis demonstrated that the performance properties, site conditions and material logistics, and social impact criteria were consistently prioritized. The critical sub-criteria identified were fire resistance, watertightness, local availability, occupant health, and safety and protection. For the Monte Calo simulations, the predictions aligned with the pilot study, enhancing the robustness of the results.
{"title":"Prioritizing Indicators for Material Selection in Prefabricated Wooden Construction","authors":"M. R. Cabral, Pierre Blanchet","doi":"10.3390/buildings14010063","DOIUrl":"https://doi.org/10.3390/buildings14010063","url":null,"abstract":"Material selection in buildings profoundly affects project success, encompassing durability, maintenance, customer satisfaction, production systems, lifecycle, usage, environment, and costs. Yet, there is a need for further research on indicators for choosing materials in prefabricated buildings. Therefore, this study’s main objective was to identify the indicators (criteria and sub-criteria) for selecting materials for prefabricated wooden construction and, subsequently, categorize these criteria and sub-criteria based on the perspective of industry professionals. To achieve this goal, three phases were carried out. First, a literature review was conducted to identify potential criteria for choosing structural and envelope materials in wooden prefabricated buildings. Second, a pilot survey was conducted in Canada and the United States to classify the priority order of the criteria obtained from the literature based on professionals’ opinions. Finally, Monte Carlo simulations were conducted with different iterations (1000, 10,000, and 100,000) using the data obtained from the previous phase to improve decision-making and classification processes. For the indicators to select materials, the literature review identified seven main criteria: performance properties, green materials, energy efficiency, circular economy, site conditions and material logistics, standards, and social impact. These criteria contained a total of 25 sub-criteria. The pilot survey data analysis demonstrated that the performance properties, site conditions and material logistics, and social impact criteria were consistently prioritized. The critical sub-criteria identified were fire resistance, watertightness, local availability, occupant health, and safety and protection. For the Monte Calo simulations, the predictions aligned with the pilot study, enhancing the robustness of the results.","PeriodicalId":48546,"journal":{"name":"Buildings","volume":"10 6","pages":""},"PeriodicalIF":3.8,"publicationDate":"2023-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139158630","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-25DOI: 10.3390/buildings14010066
Dongkyu Lee, Jinhwa Jeong, Young Tae Chae
An effective control of air handling unit (AHU) systems is crucial not only for managing the energy consumption of buildings but ensuring indoor thermal comfort for occupants. Although the initial control schema of AHU is appropriate at installation and testing, it is frequently necessary to adjust the control variables due to the changing thermal response of the building envelope and space usage. This paper presents a novel optimization process for the control parameters of old AHU systems in existing commercial buildings without system downtime and massive operational data. First, calibrating the building and system simulator with limited system operation data and unknown building parameters can provide identical responses to the system operation with the Hooke–Jeeves algorithm during the cooling season. The deep deterministic policy gradient algorithm is employed to determine the optimal control parameters for the valve opening position of the cooling coil within less than three hours of training based on the calibrated simulator. By using actual implementations with the developed optimal control variables for an old AHU in a real building, the proposed auto-tuned PID control in the simulator and with machine learning improves thermal environments with a steady room temperature (23.5 ± 0.5 °C) by 97% in occupied periods. It is also proved that this can reduce cooling energy consumption by up to 13.71% on a daily average. The successful AHU controller can improve not only the stability of AHU systems but the efficiency of a building’s energy use and indoor thermal comfort.
{"title":"Application of Deep Reinforcement Learning for Proportional–Integral–Derivative Controller Tuning on Air Handling Unit System in Existing Commercial Building","authors":"Dongkyu Lee, Jinhwa Jeong, Young Tae Chae","doi":"10.3390/buildings14010066","DOIUrl":"https://doi.org/10.3390/buildings14010066","url":null,"abstract":"An effective control of air handling unit (AHU) systems is crucial not only for managing the energy consumption of buildings but ensuring indoor thermal comfort for occupants. Although the initial control schema of AHU is appropriate at installation and testing, it is frequently necessary to adjust the control variables due to the changing thermal response of the building envelope and space usage. This paper presents a novel optimization process for the control parameters of old AHU systems in existing commercial buildings without system downtime and massive operational data. First, calibrating the building and system simulator with limited system operation data and unknown building parameters can provide identical responses to the system operation with the Hooke–Jeeves algorithm during the cooling season. The deep deterministic policy gradient algorithm is employed to determine the optimal control parameters for the valve opening position of the cooling coil within less than three hours of training based on the calibrated simulator. By using actual implementations with the developed optimal control variables for an old AHU in a real building, the proposed auto-tuned PID control in the simulator and with machine learning improves thermal environments with a steady room temperature (23.5 ± 0.5 °C) by 97% in occupied periods. It is also proved that this can reduce cooling energy consumption by up to 13.71% on a daily average. The successful AHU controller can improve not only the stability of AHU systems but the efficiency of a building’s energy use and indoor thermal comfort.","PeriodicalId":48546,"journal":{"name":"Buildings","volume":"14 4","pages":""},"PeriodicalIF":3.8,"publicationDate":"2023-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139157659","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-25DOI: 10.3390/buildings14010062
Dmitry Manasreh, Munir D. Nazzal, A. Abbas
Given the crucial importance of pavement marking retroreflectivity in ensuring visibility for road safety, this research investigates the correlation between pavement marking reflectivity and LiDAR data. Empirical data were collected from eight road sections using both a handheld retroreflectometer and a mobile LiDAR. The approach proposed focuses on extracting important features from pavement marking regions of the LiDAR point cloud. A comprehensive feature extraction and feature selection process was employed. In addition, a well-rounded selection of learning algorithms was evaluated. A rigorous hold-out evaluation was incorporated, ensuring that the reported performance metrics were robustly generalizable. The best performing model was able to achieve an R2 of 0.824 on unseen data. The findings of this study illuminate the potential for leveraging relatively inexpensive mobile LiDAR sensors in combination with machine learning techniques in conducting efficient pavement marking assessments, not only to detect completely degraded markings, but to accurately estimate retroreflective properties.
{"title":"Feature-Centric Approach for Learning-Based Prediction of Pavement Marking Retroreflectivity from Mobile LiDAR Data","authors":"Dmitry Manasreh, Munir D. Nazzal, A. Abbas","doi":"10.3390/buildings14010062","DOIUrl":"https://doi.org/10.3390/buildings14010062","url":null,"abstract":"Given the crucial importance of pavement marking retroreflectivity in ensuring visibility for road safety, this research investigates the correlation between pavement marking reflectivity and LiDAR data. Empirical data were collected from eight road sections using both a handheld retroreflectometer and a mobile LiDAR. The approach proposed focuses on extracting important features from pavement marking regions of the LiDAR point cloud. A comprehensive feature extraction and feature selection process was employed. In addition, a well-rounded selection of learning algorithms was evaluated. A rigorous hold-out evaluation was incorporated, ensuring that the reported performance metrics were robustly generalizable. The best performing model was able to achieve an R2 of 0.824 on unseen data. The findings of this study illuminate the potential for leveraging relatively inexpensive mobile LiDAR sensors in combination with machine learning techniques in conducting efficient pavement marking assessments, not only to detect completely degraded markings, but to accurately estimate retroreflective properties.","PeriodicalId":48546,"journal":{"name":"Buildings","volume":"38 3 1","pages":""},"PeriodicalIF":3.8,"publicationDate":"2023-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139158994","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-25DOI: 10.3390/buildings14010067
Peiwen Shen, Yue Chen, Song Ma, Yong Yan
The concrete-filled steel tubular (CFST) arch bridge has achieved significant development in recent years due to its unique mechanical performance and technical advantages. However, due to the lagging theoretical research compared to engineering practice, many problems have been exposed in the existing bridges, resulting in adverse social impacts and enormous economic losses. With the increasing prominence of safety issues in CFST arch bridges, it is necessary to assess their safety condition in service. This paper establishes a safety assessment index system for CFST arch bridges using the fuzzy analytic hierarchy process (AHP) based on an exponential scale. The assessment method proposed includes the following main points: (1) Bridge safety assessment is closely related to the load-bearing capacity of components. This study proposes an assessment index that comprehensively considers both the defect conditions and the design load-bearing capacity of components for the safety assessment. (2) The exponential scale method is introduced to safety assessment for the first time, and the AHP based on an exponential scale is applied to calculate the component weights. (3) Considering the specific structural characteristics of CFST arch bridges, this study provides a detailed division of component types and calculates the component weights. By combining the component assessment indexes, a comprehensive safety assessment index system is established, and a safety assessment method for CFST arch bridges is proposed. (4) Taking the Jiantiao Bridge in Zhejiang Province as an engineering case, the load-bearing capacity of components is calculated using finite element software ANSYS 19.1. Based on the established safety assessment index system, the safety of the bridge is assessed by integrating the inspection results. (5) Software for the safety assessment of a CFST arch bridge is developed using Visual Basic, and the assessment results align well with the actual condition of the bridge.
{"title":"Safety Assessment Method of Concrete-Filled Steel Tubular Arch Bridge by Fuzzy Analytic Hierarchy Process","authors":"Peiwen Shen, Yue Chen, Song Ma, Yong Yan","doi":"10.3390/buildings14010067","DOIUrl":"https://doi.org/10.3390/buildings14010067","url":null,"abstract":"The concrete-filled steel tubular (CFST) arch bridge has achieved significant development in recent years due to its unique mechanical performance and technical advantages. However, due to the lagging theoretical research compared to engineering practice, many problems have been exposed in the existing bridges, resulting in adverse social impacts and enormous economic losses. With the increasing prominence of safety issues in CFST arch bridges, it is necessary to assess their safety condition in service. This paper establishes a safety assessment index system for CFST arch bridges using the fuzzy analytic hierarchy process (AHP) based on an exponential scale. The assessment method proposed includes the following main points: (1) Bridge safety assessment is closely related to the load-bearing capacity of components. This study proposes an assessment index that comprehensively considers both the defect conditions and the design load-bearing capacity of components for the safety assessment. (2) The exponential scale method is introduced to safety assessment for the first time, and the AHP based on an exponential scale is applied to calculate the component weights. (3) Considering the specific structural characteristics of CFST arch bridges, this study provides a detailed division of component types and calculates the component weights. By combining the component assessment indexes, a comprehensive safety assessment index system is established, and a safety assessment method for CFST arch bridges is proposed. (4) Taking the Jiantiao Bridge in Zhejiang Province as an engineering case, the load-bearing capacity of components is calculated using finite element software ANSYS 19.1. Based on the established safety assessment index system, the safety of the bridge is assessed by integrating the inspection results. (5) Software for the safety assessment of a CFST arch bridge is developed using Visual Basic, and the assessment results align well with the actual condition of the bridge.","PeriodicalId":48546,"journal":{"name":"Buildings","volume":"14 10","pages":""},"PeriodicalIF":3.8,"publicationDate":"2023-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139158787","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-25DOI: 10.3390/buildings14010065
Laixiu Cheng, Junfeng Cheng
Metal roof systems were widely utilized in various important buildings; however, cases of wind damage were often observed. In this paper, wind uplift tests of standing seam aluminum magnesium manganese and continuous welded stainless-steel roof systems were conducted, and the wind resistance bearing capacity and mechanical properties of key joints in the two roof systems were compared and analyzed. Strain gauges and displacement sensors were arranged at different structural layers and key nodes of the roof system to compare and analyze the stress and displacement changes. The results showed that the wind resistance capacity of the continuous welded stainless-steel roof system was more than 25% higher than that of the standing seam aluminum magnesium manganese roof system. The stress and displacement of the roof system gradually increased with the increase in wind load. Obvious differences in stress at different positions of the two roof systems were identified. The stress at the roof panel of the roof system was greater than that of other structural layers, and the maximum displacement of the roof panel in the elastic stage could reach more than 97.5 mm. The fitting coefficient between the test and the finite element was 0.976, and the ultimate bearing capacity of Specimen B was 479.64 MPa. The research results of this paper can provide some data support and reference for engineering design and applications.
金属屋顶系统被广泛应用于各种重要建筑中，但经常出现风灾。本文对立缝铝镁锰屋面系统和连续焊接不锈钢屋面系统进行了抗风翘起试验，对比分析了两种屋面系统的抗风承载力和关键连接处的力学性能。在屋面系统的不同结构层和关键节点上布置了应变仪和位移传感器，以比较和分析应力和位移的变化。结果表明，连续焊接不锈钢屋面系统的抗风能力比立缝铝镁锰屋面系统高出 25% 以上。随着风荷载的增加，屋面系统的应力和位移逐渐增大。两种屋面系统不同位置的应力存在明显差异。屋面系统屋面板处的应力大于其他结构层，屋面板在弹性阶段的最大位移可达 97.5 mm 以上。试验与有限元的拟合系数为 0.976，试样 B 的极限承载力为 479.64 MPa。本文的研究成果可为工程设计和应用提供一定的数据支持和参考。
{"title":"Experimental Study on Static Wind Uplift Resistance of Roofing Systems","authors":"Laixiu Cheng, Junfeng Cheng","doi":"10.3390/buildings14010065","DOIUrl":"https://doi.org/10.3390/buildings14010065","url":null,"abstract":"Metal roof systems were widely utilized in various important buildings; however, cases of wind damage were often observed. In this paper, wind uplift tests of standing seam aluminum magnesium manganese and continuous welded stainless-steel roof systems were conducted, and the wind resistance bearing capacity and mechanical properties of key joints in the two roof systems were compared and analyzed. Strain gauges and displacement sensors were arranged at different structural layers and key nodes of the roof system to compare and analyze the stress and displacement changes. The results showed that the wind resistance capacity of the continuous welded stainless-steel roof system was more than 25% higher than that of the standing seam aluminum magnesium manganese roof system. The stress and displacement of the roof system gradually increased with the increase in wind load. Obvious differences in stress at different positions of the two roof systems were identified. The stress at the roof panel of the roof system was greater than that of other structural layers, and the maximum displacement of the roof panel in the elastic stage could reach more than 97.5 mm. The fitting coefficient between the test and the finite element was 0.976, and the ultimate bearing capacity of Specimen B was 479.64 MPa. The research results of this paper can provide some data support and reference for engineering design and applications.","PeriodicalId":48546,"journal":{"name":"Buildings","volume":"5 4","pages":""},"PeriodicalIF":3.8,"publicationDate":"2023-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139157889","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-24DOI: 10.3390/buildings14010057
S. Khusru, David P. Thambiratnam, Mohamed Elchalakani, S. Fawzia
Rubberised concrete, utilised as infill material within single- or double-skin confinements, has emerged as a sustainable solution, offering improved ductility in structures. Past studies have indicated promising results regarding the axial response of hybrid columns comprising filament wound exterior tubes, rubberised concrete infill, and steel interior tubes. This paper investigates the response of such hybrid columns under eccentric compression using validated numerical techniques. An extensive parametric study is conducted to explore the effects of load eccentricity, rubber percentage, concrete strength, and steel tube strength. Results show that despite credible increases in rubber percentage and load eccentricity, the columns have reasonably good performance. The findings facilitate the prediction of the eccentric behaviour of these hybrid columns across varying rubber percentages, confirming its viability for practical applications under realistic eccentric load conditions. The results further affirm the suitability of this hybrid column in scenarios that necessitate higher ductility.
{"title":"Behaviour of Slender Hybrid Rubberised Concrete Double Skin Tubular Columns under Eccentric Loading","authors":"S. Khusru, David P. Thambiratnam, Mohamed Elchalakani, S. Fawzia","doi":"10.3390/buildings14010057","DOIUrl":"https://doi.org/10.3390/buildings14010057","url":null,"abstract":"Rubberised concrete, utilised as infill material within single- or double-skin confinements, has emerged as a sustainable solution, offering improved ductility in structures. Past studies have indicated promising results regarding the axial response of hybrid columns comprising filament wound exterior tubes, rubberised concrete infill, and steel interior tubes. This paper investigates the response of such hybrid columns under eccentric compression using validated numerical techniques. An extensive parametric study is conducted to explore the effects of load eccentricity, rubber percentage, concrete strength, and steel tube strength. Results show that despite credible increases in rubber percentage and load eccentricity, the columns have reasonably good performance. The findings facilitate the prediction of the eccentric behaviour of these hybrid columns across varying rubber percentages, confirming its viability for practical applications under realistic eccentric load conditions. The results further affirm the suitability of this hybrid column in scenarios that necessitate higher ductility.","PeriodicalId":48546,"journal":{"name":"Buildings","volume":"1983 9","pages":""},"PeriodicalIF":3.8,"publicationDate":"2023-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139160356","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-24DOI: 10.3390/buildings14010056
Yi Shen, Shuangchi Sun, Wei Sun, Long Zhou, Zhongkai Huang
This study aims to investigate the factors and consequences of gas deflagration accidents in metro shield tunnels based on on-site investigation and numerical analysis. We built a numerical model and detection process for an underground shield tunnel subjected to an internal explosion from an actual accident. The tunnel geometry under consideration is the same as that used for the metro line. Concerning the limitations of research on the failure and recovery mechanism of shield segmental linings under the action of internal explosion load, an explosion accident of a shield segmental lining under construction caused by the shield tunneling machine destroying natural gas pipelines was discussed, in which the structure failure characteristics during the explosion and the structure repair method after the explosion were investigated. An interval repair scheme was proposed, which provides experience for the treatment of similar engineering accidents. To investigate the gas explosion within the tunnel during the accident, the finite element software Ansys LS-DYNA with the arbitrary Lagrangian–Eulerian (ALE) technique was employed to simulate the explosion scenario. Dynamic analyses were carried out to reproduce the blast scenario. The stress distribution within the segmental lining as well as the lining’s deformation were calculated. The potential applications of the treatment and planning of comparable engineering mishaps were discussed in the study.
{"title":"Understanding the Factors and Consequences of Gas Deflagration Accident in Metro Shield Tunnel: Site Investigation and Numerical Analysis","authors":"Yi Shen, Shuangchi Sun, Wei Sun, Long Zhou, Zhongkai Huang","doi":"10.3390/buildings14010056","DOIUrl":"https://doi.org/10.3390/buildings14010056","url":null,"abstract":"This study aims to investigate the factors and consequences of gas deflagration accidents in metro shield tunnels based on on-site investigation and numerical analysis. We built a numerical model and detection process for an underground shield tunnel subjected to an internal explosion from an actual accident. The tunnel geometry under consideration is the same as that used for the metro line. Concerning the limitations of research on the failure and recovery mechanism of shield segmental linings under the action of internal explosion load, an explosion accident of a shield segmental lining under construction caused by the shield tunneling machine destroying natural gas pipelines was discussed, in which the structure failure characteristics during the explosion and the structure repair method after the explosion were investigated. An interval repair scheme was proposed, which provides experience for the treatment of similar engineering accidents. To investigate the gas explosion within the tunnel during the accident, the finite element software Ansys LS-DYNA with the arbitrary Lagrangian–Eulerian (ALE) technique was employed to simulate the explosion scenario. Dynamic analyses were carried out to reproduce the blast scenario. The stress distribution within the segmental lining as well as the lining’s deformation were calculated. The potential applications of the treatment and planning of comparable engineering mishaps were discussed in the study.","PeriodicalId":48546,"journal":{"name":"Buildings","volume":"506 1","pages":""},"PeriodicalIF":3.8,"publicationDate":"2023-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139160799","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-24DOI: 10.3390/buildings14010055
Yachao Tang, Hongnan Li
An innovative type of precast braced concrete shear (PBCS) wall has been tested and verified to have comparable shear resistances relative to conventional cast-in-place reinforced concrete (RC) shear walls. The triangular or rectangular embedded expanded polystyrene (EPS) boards in PBCS wall panels can not only considerably reduce concrete use but also reduce the structural weight. To understand the functions of EPS boards in more depth, this paper investigates the effects of the thickness ratio of different shapes of EPS on the hysteretic behaviors of PBCS walls with various shear span ratios (SSRs). The finite element (FE) models of PBCS walls based on the multi-layer shell element are developed and verified to be sufficiently accurate in comparison with the experimental results. The analysis results indicate that the bearing capacity, lateral stiffness and ductility of PBCS walls show a downward trend with the increase in the thickness ratio of EPS boards. The rectangular EPS board has a more pronounced effect on weight reduction as well as concrete use reduction compared to the triangular EPS board under the same thickness ratio. The formulations regarding the bearing capacity are developed and show good agreement with the numerical results. The thickness ratio limit for PBCS walls to satisfy the ductility requirement is addressed. This investigation not only provides insight into the cyclic behavior of PBCS walls with varied thickness ratios but also demonstrates the potential applicability of PBCS walls in precast concrete (PC) structures for both thermal insulation and earthquake resistance purposes.
{"title":"Effects of Embedded Expanded Polystyrene Boards on the Hysteretic Behavior of Innovative Precast Braced Concrete Shear Walls","authors":"Yachao Tang, Hongnan Li","doi":"10.3390/buildings14010055","DOIUrl":"https://doi.org/10.3390/buildings14010055","url":null,"abstract":"An innovative type of precast braced concrete shear (PBCS) wall has been tested and verified to have comparable shear resistances relative to conventional cast-in-place reinforced concrete (RC) shear walls. The triangular or rectangular embedded expanded polystyrene (EPS) boards in PBCS wall panels can not only considerably reduce concrete use but also reduce the structural weight. To understand the functions of EPS boards in more depth, this paper investigates the effects of the thickness ratio of different shapes of EPS on the hysteretic behaviors of PBCS walls with various shear span ratios (SSRs). The finite element (FE) models of PBCS walls based on the multi-layer shell element are developed and verified to be sufficiently accurate in comparison with the experimental results. The analysis results indicate that the bearing capacity, lateral stiffness and ductility of PBCS walls show a downward trend with the increase in the thickness ratio of EPS boards. The rectangular EPS board has a more pronounced effect on weight reduction as well as concrete use reduction compared to the triangular EPS board under the same thickness ratio. The formulations regarding the bearing capacity are developed and show good agreement with the numerical results. The thickness ratio limit for PBCS walls to satisfy the ductility requirement is addressed. This investigation not only provides insight into the cyclic behavior of PBCS walls with varied thickness ratios but also demonstrates the potential applicability of PBCS walls in precast concrete (PC) structures for both thermal insulation and earthquake resistance purposes.","PeriodicalId":48546,"journal":{"name":"Buildings","volume":"2012 18","pages":""},"PeriodicalIF":3.8,"publicationDate":"2023-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139160284","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Swivel bridge construction (SBC) technology has significant advantages in building bridges that span existing railway lines (ERLs), but it also entails complex risks from ‘skylight’ windows and railway boundaries. A notable challenge is the relationships and interdependencies among these risks, which collectively increase safety hazards through mutual influence. Prior research has typically focused on mitigating the risks inherent in particular tasks or operations, with less emphasis on the risks from interdependencies. A novel framework was developed to explore this research gap by integrating fuzzy logic, interpretive structural modeling (ISM) and the cross-impact matrix multiplication applied to classification (MICMAC) approach (Fuzzy-ISM-MICMAC) to investigate the relationships and interdependencies among the risks of SBC spanning ERLs and the critical points of risk control. Furthermore, the data collected from a literature review, a case analysis and expert interviews resulted in 28 risk factors. Then, the application of ISM distilled complex risk relationships into a clear, multilevel hierarchy, accurately illustrating the complex interrelationships among risk factors. Combined with MICMAC analysis, the research findings indicate that preliminary works such as the selection of construction technology, scheme design, construction rehearsal and the provision of safety facilities are essential for preventing risks in SBC spanning ERLs. We applied these findings to the double T-structure swivel construction of the Xiaojizhuang Bridge, where its practicality and efficiency were thoroughly tested and validated. This research’s critical contribution is identifying, clarifying and visualizing the interrelationships of the complex risk factors of SBC spanning ERLs and providing specific solutions for safety management in similar bridge construction projects. The research results and risk control recommendations offer valuable insights for managing other swivel bridge construction risks.
{"title":"Application of Fuzzy-ISM-MICMAC in the Risk Analysis Affecting Swivel Bridge Construction Spanning Existing Railway Lines: A Case Study","authors":"Chunyan Peng, Jiquan Wang, Huihua Chen, Runxi Tang","doi":"10.3390/buildings14010052","DOIUrl":"https://doi.org/10.3390/buildings14010052","url":null,"abstract":"Swivel bridge construction (SBC) technology has significant advantages in building bridges that span existing railway lines (ERLs), but it also entails complex risks from ‘skylight’ windows and railway boundaries. A notable challenge is the relationships and interdependencies among these risks, which collectively increase safety hazards through mutual influence. Prior research has typically focused on mitigating the risks inherent in particular tasks or operations, with less emphasis on the risks from interdependencies. A novel framework was developed to explore this research gap by integrating fuzzy logic, interpretive structural modeling (ISM) and the cross-impact matrix multiplication applied to classification (MICMAC) approach (Fuzzy-ISM-MICMAC) to investigate the relationships and interdependencies among the risks of SBC spanning ERLs and the critical points of risk control. Furthermore, the data collected from a literature review, a case analysis and expert interviews resulted in 28 risk factors. Then, the application of ISM distilled complex risk relationships into a clear, multilevel hierarchy, accurately illustrating the complex interrelationships among risk factors. Combined with MICMAC analysis, the research findings indicate that preliminary works such as the selection of construction technology, scheme design, construction rehearsal and the provision of safety facilities are essential for preventing risks in SBC spanning ERLs. We applied these findings to the double T-structure swivel construction of the Xiaojizhuang Bridge, where its practicality and efficiency were thoroughly tested and validated. This research’s critical contribution is identifying, clarifying and visualizing the interrelationships of the complex risk factors of SBC spanning ERLs and providing specific solutions for safety management in similar bridge construction projects. The research results and risk control recommendations offer valuable insights for managing other swivel bridge construction risks.","PeriodicalId":48546,"journal":{"name":"Buildings","volume":"566 2","pages":""},"PeriodicalIF":3.8,"publicationDate":"2023-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139160645","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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