Developments in the Built Environment最新文献_第6页

Urban heat islands' effects on the thermo-energy performance of buildings according to their socio-economic factors 城市热岛根据社会经济因素对建筑物热能性能的影响

IF 6.2 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Developments in the Built Environment

Pub Date : 2024-11-04 DOI: 10.1016/j.dibe.2024.100566

Rafael E. López-Guerrero , Konstantin Verichev , Juan Pablo Cárdenas-Ramírez , Manuel Carpio

Urban areas experience the urban heat island (UHI) effect, which affects the thermal comfort and energy consumption of buildings. These consequences could vary depending on the socio-economic status of the neighbourhoods. Few studies have investigated how UHI affects socio-economically contrasting districts in thermal comfort and energy performance. Therefore, the primary goal of this research is to evaluate and compare the energy efficiency and thermal comfort conditions of residential buildings in the same city (Temuco, Chile) but located in socio-economically contrasting neighbourhoods. Urban weather files were first modelled in four urban zones using UWG software. Also, EnergyPlus building simulations were conducted to evaluate discomfort hours in adaptive comfort models and energy performance. The results showed annual average UHI intensities between 1.5 and 2.5 K. Urban–rural cooling energy load differences ranged between 12.47% and 38.92%, while heating energy load differences ranged between −20.47% and −81.95%. These distinctions depended on the urban zone, residence model analysed, or energy building standard applied. Similarly, urban-rural differences in thermal comfort times varied from 0.5% to 100%. Results illustrate that the risk of overheating could increase in socio-economically vulnerable areas. This issue could worsen if urban segregation continues to generate poor urban design in low-income districts.

城市热岛效应（UHI）会影响建筑物的热舒适度和能源消耗。这些后果可能因居民区的社会经济状况而异。很少有研究调查过 UHI 如何影响社会经济对比强烈的地区的热舒适度和能耗表现。因此，本研究的主要目标是评估和比较位于同一城市（智利特木科）但社会经济状况截然不同的居民区的住宅建筑的能源效率和热舒适度。首先使用 UWG 软件对四个城市区域的城市天气文件进行建模。此外，还进行了 EnergyPlus 建筑模拟，以评估适应性舒适度模型中的不适时间和能源性能。结果显示，年平均 UHI 强度在 1.5 至 2.5 K 之间，城乡制冷能源负荷差异在 12.47% 至 38.92% 之间，而采暖能源负荷差异在 -20.47% 至 -81.95% 之间。这些差异取决于城市区域、所分析的住宅模型或所采用的建筑节能标准。同样，热舒适时间的城乡差异从 0.5% 到 100% 不等。结果表明，社会经济脆弱地区的过热风险可能会增加。如果城市隔离继续在低收入地区造成不良的城市设计，这一问题可能会恶化。

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引用次数: 0

Effects of superabsorbent polymer and natural zeolite on shrinkage, mechanical properties, and porosity in ultra-high performance concretes 超吸收聚合物和天然沸石对超高性能混凝土收缩率、机械性能和孔隙率的影响

IF 6.2 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Developments in the Built Environment

Pub Date : 2024-11-02 DOI: 10.1016/j.dibe.2024.100568

Yuxiang Tan , Bo Li , Yung-Tsang Chen , Yifeng Ling , Weizhuo Shi

The low water-to-binder ratio of ultra-high performance concrete (UHPC) often causes shrinkage and cracking due to early-age self-desiccation. This leads to significant initial dimensional instability, which may compromise structural integrity. As a promising solution, internal curing agents such as superabsorbent polymers (SAP) and natural zeolite have the potential to mitigate shrinkage and achieve self-stressing properties. This research aims to provide a comprehensive comparison between SAP and zeolite's effects within a consistent UHPC formulation. Six UHPC mixtures (including the reference mixture) were designed: three with SAP dosages of 0.2%, 0.4%, and 0.6% by cement mass, and two with zeolite replacing silica fume at 25% and 50% by mass. Various testing methods, including autogenous and drying shrinkage assessment, heat of hydration and thermogravimetric analysis, compressive strength evaluation, mercury intrusion porosimetry (MIP), nuclear magnetic resonance (NMR), were employed to assess the mixtures at different stages of curing. The result reveals that the incorporation of SAP and zeolite in the mixtures significantly reduces UHPC's early-age autogenous shrinkage. Moreover, SAP and zeolite additions impact mechanical properties, demonstrating that a balance between shrinkage control and compressive strength can be reached, through an optimization of the additions to achieve the desired performance. Microstructural analysis through MIP and NMR reveals increased overall porosity of the UHPC with SAP and zeolite, suggesting that low-field NMR can be a valuable tool for complementing conventional test methods. The outcome of this study provided valuable insights into optimizing the balance between durability and mechanical performance, paving the way for more sustainable and cost-effective applications of UHPC in modern construction practices.

超高性能混凝土（UHPC）的水粘结比很低，常常会因早期龄期自干燥而导致收缩和开裂。这会导致初始尺寸严重不稳定，从而损害结构的完整性。作为一种有前途的解决方案，超吸收聚合物（SAP）和天然沸石等内部固化剂有可能缓解收缩并实现自应力特性。本研究旨在全面比较 SAP 和沸石在一致的 UHPC 配方中的效果。研究人员设计了六种 UHPC 混合物（包括参考混合物）：三种混合物的 SAP 用量分别为水泥质量的 0.2%、0.4% 和 0.6%，两种混合物的沸石取代硅灰的比例分别为 25% 和 50%。采用了各种测试方法，包括自生收缩和干燥收缩评估、水化热和热重分析、抗压强度评估、汞侵入孔隙比拟法（MIP）、核磁共振（NMR），以评估处于不同固化阶段的混合物。结果表明，在混合物中加入 SAP 和沸石可显著降低 UHPC 早期的自生收缩。此外，SAP 和沸石的添加对机械性能也有影响，这表明可以通过优化添加量来实现收缩控制和抗压强度之间的平衡，从而达到所需的性能。通过 MIP 和 NMR 进行的微观结构分析表明，添加了 SAP 和沸石的 UHPC 整体孔隙率增加，这表明低场 NMR 可以成为补充传统测试方法的重要工具。这项研究的成果为优化耐久性和机械性能之间的平衡提供了宝贵的见解，为在现代建筑实践中以更具可持续性和成本效益的方式应用 UHPC 铺平了道路。

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引用次数: 0

Explainable machine learning model for load-deformation correlation in long-span suspension bridges using XGBoost-SHAP 利用 XGBoost-SHAP 建立大跨度悬索桥荷载-变形相关性的可解释机器学习模型

IF 6.2 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Developments in the Built Environment

Pub Date : 2024-11-02 DOI: 10.1016/j.dibe.2024.100569

Mingyang Chen , Jingzhou Xin , Qizhi Tang , Tianyu Hu , Yin Zhou , Jianting Zhou

The deformation of long-span suspension bridges in multiple loads is an important indictor to reflect their operation state. However, the correlation between multiple loads and structural deformation is difficult to quantify. Therefore, this study proposes an explainable machine learning model for the load-deformation correlation in long-span suspension bridges using eXtreme Gradient Boosting (XGBoost) and SHapley Additive exPlanations (SHAP). Firstly, the structural health monitoring system for a suspension bridge was used to construct the dataset for the training and testing of XGBoost model. Herein, temperature, wind and vehicle loads were used as the input variables, while midspan deflections and expansion joint displacements were treated as outputs. Subsequently, the hyperparameters of XGBoost model were optimized using grid search and 5-fold cross-validation to ensure its prediction performance. Then, the prediction results were compared with other four machine learning methods (i.e., linear regression, artificial neural networks, gradient boosted decision trees and CatBoost). Finally, the correlation between different loads and displacement responses were explained by the SHAP method to identify the contribution of the loads on deformation. The results show that the XGBoost model has the highest prediction accuracy. Compared to vehicle and wind loads, temperature significantly affects the deformation of long-span suspension bridges during daily operation. The effects of temperature and wind on bridge deformation are independent, and there is no significant interaction between these two factors.

大跨度悬索桥在多重荷载作用下的变形是反映其运行状态的重要指标。然而，多重荷载与结构变形之间的相关性难以量化。因此，本研究利用 eXtreme Gradient Boosting（XGBoost）和 SHapley Additive exPlanations（SHAP）为大跨度悬索桥的荷载-变形相关性提出了一种可解释的机器学习模型。首先，利用悬索桥结构健康监测系统构建数据集，用于 XGBoost 模型的训练和测试。其中，温度、风荷载和车辆荷载被用作输入变量，而中跨挠度和伸缩缝位移被视为输出变量。随后，利用网格搜索和 5 倍交叉验证对 XGBoost 模型的超参数进行了优化，以确保其预测性能。然后，将预测结果与其他四种机器学习方法（即线性回归、人工神经网络、梯度提升决策树和 CatBoost）进行比较。最后，用 SHAP 方法解释了不同荷载和位移响应之间的相关性，以确定荷载对变形的贡献。结果表明，XGBoost 模型的预测精度最高。与车辆荷载和风荷载相比，温度对大跨度悬索桥在日常运营中的变形影响更大。温度和风对桥梁变形的影响是独立的，这两个因素之间没有明显的交互作用。

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引用次数: 0

Extending Information Delivery Specifications for digital building permit requirements 扩展数字建筑许可要求的信息交付规范

IF 6.2 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Developments in the Built Environment

Pub Date : 2024-10-29 DOI: 10.1016/j.dibe.2024.100560

Simon Fischer , Harald Urban , Christian Schranz , Patrick Loibl , Léon van Berlo

This paper examines the potential for extending the Information Delivery Specification (IDS) schema to facilitate its integration into the building permit process. IDS is an open specification for defining and verifying information requirements for digital building models. Building authorities have already begun utilising IDS to define information requirements for automated code compliance checks. However, this requires the filtering of elements beyond the current scope of IDS. Such filtering functionality also has the potential to facilitate simple code compliance checks. This paper presents concepts for extending IDS to define information requirements for escape route analysis and code compliance checks for Austrian fire resistance regulations. The main extension was the filtering of elements depending on characteristics of related elements. Nesting existing functionalities enabled the schema to remain simple. A prototype implementation demonstrated that minor extensions to the IDS schema can significantly enhance its functionality, paving the way for broader applications of IDS.

本文探讨了扩展信息交付规范（IDS）模式的可能性，以促进其与建筑许可流程的整合。IDS 是一种开放式规范，用于定义和验证数字建筑模型的信息要求。建筑管理机构已经开始利用 IDS 来定义自动规范合规性检查的信息要求。然而，这需要对超出 IDS 当前范围的元素进行过滤。这种过滤功能还有可能促进简单的规范符合性检查。本文介绍了扩展 IDS 的概念，以便为奥地利防火法规的逃生路线分析和法规符合性检查定义信息要求。主要的扩展功能是根据相关元素的特征对元素进行过滤。现有功能的嵌套使模式保持简单。原型实施表明，对 IDS 模式的微小扩展可以显著增强其功能，为 IDS 的更广泛应用铺平道路。

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引用次数: 0

Effect of shell composition on watertightness and mechanical performance of cement-based capsules used as self-healing additives of cement 外壳成分对用作水泥自愈合添加剂的水泥基胶囊的水密性和机械性能的影响

IF 6.2 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Developments in the Built Environment

Pub Date : 2024-10-28 DOI: 10.1016/j.dibe.2024.100565

I. Karatasios, S. Papaioannou, E. Tziviloglou, V. Kilikoglou

The aim of this work is the development of cementitious macro-capsules for self-healing cement and concrete materials. Emphasis is placed on shell properties, including size, thickness, strength, and volume to active component ratio. This enhancement is aimed at protecting the healing agent and ensuring adequate reactivity upon crack formation, surpassing survivability considerations. To this direction, core/shell particles have been produced following the pan-coating method, while different types and concentrations of setting acceleration solutions for the shell stabilization were studied. The formation of core-shell capsules encompasses the formation a spherical core through agglomeration, followed by simultaneous spraying of cement powder and a setting acceleration solution for the shell formation, under continuous rotation. The microstructural characteristics of the shell were studied through scanning electron microscopy (SEM), while the reactivity of the protected core (reactive agent) inside the hardened mortar mixtures was evaluated using thermogravimetric analysis (TGA). Moreover, the crushing load of the capsules under compression and their survivability during mixing process were examined and interpreted in relation to their diameter, circularity, and shell thickness.

The results revealed the ability of the encapsulation methodology proposed to tailor the shell properties and modify the capsule properties so as satisfy the requirements of different applications. The use of setting accelerators during shell formation proved essential for enhancing the density and the strength of the shell layer. As a consequence, this leads to macro-scale capsules with elevated survivability rate and core reactivity.

这项工作的目的是开发用于自愈合水泥和混凝土材料的水泥基大胶囊。重点是外壳性能，包括尺寸、厚度、强度和体积与活性成分的比率。这种改进旨在保护愈合剂，并确保在裂缝形成时有足够的反应能力，超越存活率的考虑。为此，我们采用泛涂层法生产了芯/壳颗粒，并研究了用于稳定壳的不同类型和浓度的凝固加速溶液。芯壳胶囊的形成包括通过聚结形成球形芯，然后在连续旋转的情况下同时喷涂水泥粉末和用于形成外壳的凝固加速溶液。通过扫描电子显微镜（SEM）研究了外壳的微观结构特征，同时使用热重分析（TGA）评估了硬化砂浆混合物中受保护核心（活性剂）的反应性。此外，还根据胶囊的直径、圆度和外壳厚度，研究和解释了胶囊在压缩过程中的压碎负荷及其在混合过程中的存活率。结果表明，所提出的封装方法能够调整外壳性能和改变胶囊性能，从而满足不同应用的要求。事实证明，在外壳形成过程中使用凝固促进剂对提高外壳层的密度和强度至关重要。因此，这导致了具有更高的存活率和核心反应活性的大尺度胶囊。

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引用次数: 0

Physicochemical properties of CO2-cured belite-rich cement with electric arc furnace reduction slag as a partial replacement 部分替代电弧炉还原渣的二氧化碳固化富褐铁矿水泥的物理化学特性

IF 6.2 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Developments in the Built Environment

Pub Date : 2024-10-24 DOI: 10.1016/j.dibe.2024.100564

Geon Noh , Gaurav Sharma , Hyeju Kim , Kunal Krishna Das , Jeong Gook Jang , Jung-Jun Park , Namkon Lee

This study investigates the physicochemical properties of CO₂-cured belite-rich cement with electric arc furnace (EAF) reduction slag as a partial replacement at varying weight percentages (0–20%). The results revealed that water-cured specimens (WRS) showed significant increases in the numbers of gel and medium capillary pores, while carbonation-cured specimens (CRS) demonstrated increases in the numbers of large capillary and macro pores. Moreover, up to 10% replacement of the slag led to a decrease in the compressive strength, accompanied by increased CO₂ absorption and reduced alkalinity. When the EAF reduction slag content increased from 15% to 20%, CRS exhibited a trend reversal in the compressive strength, marked by an increase in the pH, approaching compressive strength comparable to those of WRS. This signified that higher percentages of EAF reduction slag are advantageous for enhancing CO₂ sequestration due to the potential reactivity of magnesium oxide in EAF reduction slag with CO₂.

本研究调查了以不同重量百分比（0-20%）的电弧炉（EAF）还原渣作为部分替代物的二氧化碳固化富褐铁矿水泥的物理化学特性。结果表明，水固化试样（WRS）的凝胶和中等毛细孔数量显著增加，而碳化固化试样（CRS）的大毛细孔和宏观孔数量增加。此外，矿渣替代率高达 10% 会导致抗压强度下降，同时二氧化碳吸收量增加，碱度降低。当 EAF 还原渣的含量从 15%增加到 20%时，CRS 的抗压强度出现了逆转趋势，pH 值明显增加，抗压强度接近 WRS。这表明，由于炼焦炉还原渣中的氧化镁可能与二氧化碳发生反应，因此较高比例的炼焦炉还原渣有利于提高二氧化碳封存效果。

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引用次数: 0

Experimental modal identification of a pedestrian bridge through drive-by monitoring integrated with shared-mobility vehicles 通过与共享交通车辆相结合的驾驶式监测，对一座人行天桥进行试验性模式识别

IF 6.2 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Developments in the Built Environment

Pub Date : 2024-10-24 DOI: 10.1016/j.dibe.2024.100562

Kun Feng , David Hester , Su Taylor , Connor O'Higgins , Alan Ferguson , Zuo Zhu , Guang Zou , Myra Lydon , Juliana Early

In the context of improving resilience in transport infrastructure, an emerging approach of indirect structural health monitoring is gaining attention, known as drive-by monitoring, instrumenting a vehicle with sensors to evaluate the bridges it crosses. However, their effectiveness has predominantly been investigated in ideal scenarios, with actual real-world applications being quite scarce. The research presented in this paper explores the feasibility of combining two routes: (1) fleet emissions reduction and (2) transport resilience enhancement, through drive-by monitoring integrated with shared mobility, including electric mobility scooter and bicycle. The information from drive-by data collected from shared mobility can give valuable information on critical transport infrastructure (e.g., bridges) and such a drive-by database has the potential for network level infrastructure condition assessment. In this paper, two different drive-by roadmaps are investigated subject to the flexibility of the bridges, namely partially or fully drive-by monitoring. To validate the proposed roadmaps, a full-scale pedestrian bridge was chosen for drive-by testing, where smartphone sensors and specialised accelerometers are mounted on shared mobility for data acquisition. Experimental results demonstrate that (i) smartphone sensing can provide data with similar accuracy compared to specialised accelerometers, (ii) bridge frequencies can be easily obtained from temporarily parked shared mobility, with a maximum relative error of 1.05%, (iii) both the bridge frequencies and operational deflection shapes are successfully extracted from the moving shared mobility by using variational mode decomposition and filtering techniques, and shared mobility's GPS data along with moving speeds are collected for potential vehicle positioning and drive-by database updating.

在提高交通基础设施抗灾能力的背景下，一种新出现的间接结构健康监测方法正受到越来越多的关注，这种方法被称为 "驾车监测"，即在车辆上安装传感器，以评估其经过的桥梁。然而，这种方法的有效性主要是在理想情况下进行研究的，实际应用还很少。本文介绍的研究探讨了将两条路线结合起来的可行性：（1）减少车队排放；（2）通过将驾驶监测与共享交通（包括电动代步车和自行车）相结合，增强交通恢复能力。从共享交通中收集的驾驶数据信息可以提供重要交通基础设施（如桥梁）的宝贵信息，这样的驾驶数据库有可能用于网络级基础设施状况评估。本文根据桥梁的灵活性研究了两种不同的绕行路线图，即部分绕行监测或完全绕行监测。为了验证所提出的路线图，选择了一座完整规模的人行天桥进行绕行测试，在共享移动装置上安装智能手机传感器和专用加速度计以获取数据。实验结果表明：(i) 与专用加速度计相比，智能手机传感可提供相似精度的数据；(ii) 桥梁频率可从临时停放的共享移动设备上轻松获取，最大相对误差为 1.05%；(iii) 通过使用变模分解和滤波技术，可从移动的共享移动设备上成功提取桥梁频率和运行挠度形状，并可收集共享移动设备的 GPS 数据和移动速度，用于潜在的车辆定位和驾车测试数据库更新。

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引用次数: 0

Enhancing dynamic mechanical properties of cemented lithium mica tailings backfill with alkaline rice straw fibers: Experimental investigation and microscopic analysis 用碱性稻草纤维增强胶结锂云母尾矿回填的动态力学性能：实验研究与显微分析

IF 6.2 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Developments in the Built Environment

Pub Date : 2024-10-24 DOI: 10.1016/j.dibe.2024.100563

Daopei Zhu , Nanhui Huang , Quanmao Xiao , Zhangli Wang

Cemented lithium mica tailings backfill (CLMTB) faces dynamic loads from mining operations, affecting its stability. This study investigates the use of alkaline rice straw fibers (ARSF) to enhance CLMTB's dynamic properties. Dynamic impact tests were conducted on CLMTB specimens with varying ARSF contents, revealing that dynamic compressive strength (DCS) increased with ARSF up to 0.45% before decreasing. DCS improved with rising strain rates. The research includes analyses of stress-strain behavior, failure patterns, and energy dissipation during impacts, with scanning electron microscopy revealing the microstructural effects of ARSF on CLMTB. The findings suggest that ARSF effectively mitigates the damaging impacts of loads, significantly reducing crack development in CLMTB.

固结锂云母尾矿回填（CLMTB）面临采矿作业产生的动荷载，影响其稳定性。本研究探讨了使用碱稻草纤维（ARSF）来增强锂云母尾矿回填土的动态特性。对不同 ARSF 含量的 CLMTB 试样进行了动态冲击试验，结果表明，动态抗压强度（DCS）随 ARSF 的增加而增加，最高可达 0.45%，然后逐渐降低。随着应变率的增加，动态抗压强度也有所提高。研究包括分析应力应变行为、失效模式和冲击过程中的能量耗散，扫描电子显微镜揭示了 ARSF 对 CLMTB 的微观结构影响。研究结果表明，ARSF 能有效减轻负载的破坏性影响，显著减少 CLMTB 的裂纹发展。

引用次数: 0

A unified object and keypoint detection framework for Personal Protective Equipment use 个人防护设备使用的统一对象和关键点检测框架

IF 6.2 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Developments in the Built Environment

Pub Date : 2024-10-19 DOI: 10.1016/j.dibe.2024.100559

Bin Yang, Hongru Xiao, Binghan Zhang

Accurately detecting whether workers wear Personal Protective Equipment (PPE) in real time plays an important role in safety management. Previous studies mainly used multiple models jointly or only object detection for wearing relationship judgments. This makes it difficult to provide real-time, accurate detection of security relationships. Therefore, this paper proposes safe-wearing detection rules and a novel multi-targets and keypoints detection framework (MTKF), which is capable of accomplishing multiple classes of targets and keypoints detection simultaneously in one-stage, to get more accurate results. In order to improve the performance in the PPE and worker keypoints detection in challenging construction scenes, the detection head transformation strategy, mix group shuffle attention (MGSA) module, and the improved dual and cross-class suppression algorithm (DC-NMS) are proposed. The experimental results are implemented on one established dataset (Joint dataset) and two public datasets (SHWD and COCO), which conduct a comprehensive evaluation in multiple dimensions. Compared to the baseline model, our method improves the mAP by 2.6%–7.1%, reduces the number of parameters by at least 70%, and is able to achieve an inference speed of 155 fps.

实时准确地检测工人是否穿戴个人防护设备（PPE）在安全管理中发挥着重要作用。以往的研究主要使用多种模型联合或仅使用对象检测来进行穿戴关系判断。这就很难提供实时、准确的安全关系检测。因此，本文提出了安全佩戴检测规则和新颖的多目标和关键点检测框架（MTKF），能够在一个阶段内同时完成多类目标和关键点的检测，从而获得更准确的结果。为了提高具有挑战性的建筑场景中 PPE 和工人关键点检测的性能，提出了检测头转换策略、混合组洗牌注意（MGSA）模块和改进的双类和跨类抑制算法（DC-NMS）。实验结果在一个成熟数据集（联合数据集）和两个公开数据集（SHWD 和 COCO）上进行了多维度的综合评估。与基线模型相比，我们的方法将 mAP 提高了 2.6%-7.1%，参数数量至少减少了 70%，推理速度达到了 155 fps。

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引用次数: 0

Catenary mechanism in steel columns under extreme lateral loading: A basis for building progressive collapse analysis 极端侧向荷载下钢柱的导柱机制：建筑物渐进式倒塌分析的基础

IF 6.2 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Developments in the Built Environment

Pub Date : 2024-10-19 DOI: 10.1016/j.dibe.2024.100556

Foad Kiakojouri, Valerio De Biagi

The studies on progressive collapse have primarily focused on threat-independent methods, wherein a sudden column removal is suggested in codes. However, a real collapse scenario is necessarily threat-dependent. Focusing on blast- and impact-induced progressive collapses, the current study considers cases in which damage is concentrated in a single member, without resulting in complete column loss. It is demonstrated that the progressive collapse performance under specific threats can be better or worse compared to that of sudden column removal. Thus, dynamic column removal does not necessarily guarantee the most critical scenario, as the response in a damaged system can sometimes exceed expectations. A simple analytical model is proposed to describe in detail the observed phenomena and emphasizes the development of catenary forces in the column under lateral extreme loading scenarios. The results provide a deeper insight into the progressive collapse performance of frame systems and the involved member-level resisting mechanisms.

对渐进式坍塌的研究主要集中在与威胁无关的方法上，即在规范中建议突然移除支柱。然而，实际的倒塌情况必然与威胁有关。当前的研究侧重于爆炸和冲击引起的渐进式坍塌，考虑了损坏集中在单个构件上，但不会导致支柱完全损失的情况。研究表明，与突然移除支柱相比，在特定威胁下的渐进式坍塌性能可能更好，也可能更差。因此，动态移除支柱并不一定能保证最危急的情况，因为受损系统的响应有时会超出预期。本文提出了一个简单的分析模型来详细描述所观察到的现象，并强调了在横向极端加载情况下支柱中猫尾力的发展。研究结果有助于深入了解框架系统的渐进式坍塌性能以及所涉及的构件级抵抗机制。

引用次数: 0