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Point cloud classification and part segmentation of steel structure elements

Neural Computing and Applications 2025年第6期37卷 4387-4407页

作者： Daif, Hassan Marzouk, Mohamed Integrated Engineering Design Management Program Faculty of Engineering Cairo University Giza12613 Egypt Structural Engineering Department Faculty of Engineering Cairo University Giza12613 Egypt Badr City Cairo11829 Egypt

The classification and part segmentation of point clouds have gained significant attention in the field of artificial intelligence (AI), especially in the construction industry. However, addressing the dataset directly in AI models remains a challenge, as most existing methods are not well-suited for processing point cloud data. PointNet has emerged as an AI architecture algorithm. It transforms individual points independently to learn local and global features. This research aims to develop a comprehensive framework for classification and part segmentation for point clouds of steel structure elements. The framework enhances the accuracy of the PointNet algorithm, and it consists of three stages: (1) dataset creation;(2) model classification;and (3) part segmentation. First, the dataset creation procedure encompasses modeling steel columns, beams, and braces using Autodesk Revit software. For the classification dataset, a dataset comprising 580 columns and 920 beams is obtained. In the part segmentation dataset, five categories of steel braced frame elements are generated, yielding a total of 21,870 elements for braced frame structures. Several point cloud experiments have been applied, including adjusting the number of points in the point cloud, altering the batch size, and fine-tuning the number of epochs. These experimental settings were systematically investigated to identify the optimal combination that yields the highest (AI) model accuracy. PointNet model achieved 100% accuracy across all classification experiments, while part segmentation experiments reached up to 97.10% accuracy, with a mean intersection over union (MIOU) of 93.70%. The comprehensive analysis of the point cloud dataset is applied on an actual case study to demonstrate the practical features of the proposed research. © The Author(s) 2024.

关键词： Steel structures

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Mass Distribution Sensitivity Analysis for Global Stability Performance of Super High Aspect Ratio Tall Buildings 30th

Mass Distribution Sensitivity Analysis for Global Stability ...

引用

30th International Conference on Computational and Experimental engineering and Sciences, ICCES 2024

作者： Yu, Zhongjun Fan, Boran Zhao, Xin Tongji Architectural Design Group No. 1230 Siping Road Shanghai200092 China Department of Structural Engineering Tongji University No. 1239 Siping Road Shanghai200092 China

ISBN: (纸本)9783031829062

The overall stability performance (Stiffness-to-Mass ratio) is a governing indicator in the structural design of super-tall buildings. For many super-tall buildings with extremely high aspect ratios, overall stability performance becomes a controlling constraint. In the design of super-tall buildings, the distribution of floor mass varies, ranging from relatively uniform to designs that taper from bottom to top, placing the center of gravity lower. With technological advancements, architects are pursuing unconventional designs, such as the CITIC Tower, which narrows and then expands from bottom to top. The height of the center of gravity is a key factor affecting the overall stability performance of high-rise buildings, with a lower center of gravity indicating better stability. The specific position of the center of gravity is determined by the distribution of floor mass along the building's height. Factors influencing the mass distribution of floors include the distribution of the building's plan area, changes in the dimensions of main structural components, and the distribution of other loads and non-structural component weights. Unlike the assumptions of standard codes, these super-tall buildings with very high aspect ratios have irregular mass distributions, which may meet the prescribed Stiffness-to-Mass ratio requirements of the codes, but not the modified Stiffness-to-Mass ratios. This paper reviews the relationship between overall stability analysis methods and Stiffness-to-Mass ratio, using a two-dimensional planar model to demonstrate the stability analysis methods, comparing results from Stiffness-to-Mass ratio analysis with those from finite element numerical simulations. For buildings with uneven vertical mass distribution, a modified algorithm is used to calculate the Stiffness-to-Mass ratio, and the results are compared with those unmodified. Finally, the second-order effects of gravity under inverted triangular loads, wind loads, and earthquake forc

关键词： Floors

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Variable stiffness design optimization of fiber-reinforced composite laminates with regular and irregular holes considering fiber continuity for additive manufacturing

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Chinese Journal of Aeronautics 2025年第3期38卷 334-354页

作者： Yi LIU Zunyi DUAN Chunping ZHOU Yuan SI Chenxi GUAN Yi XIONG Bin XU Jun YAN Jihong ZHU School of Mechanics Civil Engineering&ArchitectureNorthwestern Polytechnical UniversityXi’an 710072China Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518063China Key Lab for Airborne Hi-performance Electro-magnetic Window RISACJinan 130012China School of System Design and Intelligent Manufacturing Southern University of Science and TechnologyShenzhen 518055China State Key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering MechanicsInternational Research Center for Computational MechanicsDalian University of TechnologyDalian 116024China State IJR Center of Aerospace Design and Additive Manufacturing MIIT Lab of Metal Additive Manufacturing and Innovative DesignNorthwestern Polytechnical UniversityXi’an 710072China

Fiber-reinforced composites are an ideal material for the lightweight design of aerospace structures. Especially in recent years, with the rapid development of composite additive manufacturing technology, the design optimization of variable stiffness of fiber-reinforced composite laminates has attracted widespread attention from scholars and industry. In these aerospace composite structures, numerous cutout panels and shells serve as access points for maintaining electrical, fuel, and hydraulic systems. The traditional fiber-reinforced composite laminate subtractive drilling manufacturing inevitably faces the problems of interlayer delamination, fiber fracture, and burr of the laminate. Continuous fiber additive manufacturing technology offers the potential for integrated design optimization and manufacturing with high structural performance. Considering the integration of design and manufacturability in continuous fiber additive manufacturing, the paper proposes linear and nonlinear filtering strategies based on the Normal Distribution Fiber Optimization (NDFO) material interpolation scheme to overcome the challenge of discrete fiber optimization results, which are difficult to apply directly to continuous fiber additive manufacturing. With minimizing structural compliance as the objective function, the proposed approach provides a strategy to achieve continuity of discrete fiber paths in the variable stiffness design optimization of composite laminates with regular and irregular holes. In the variable stiffness design optimization model, the number of candidate fiber laying angles in the NDFO material interpolation scheme is considered as design variable. The sensitivity information of structural compliance with respect to the number of candidate fiber laying angles is obtained using the analytical sensitivity analysis method. Based on the proposed variable stiffness design optimization method for complex perforated composite laminates, the numerical examples cons

关键词： Variable stiffness composite laminates Discrete material interpolation scheme Normal distribution fiber optimization Discrete fiber continuous filtering strategy Additive manufacturing of composite laminates

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Pore structure characterization of porous building material by X-ray computed tomography (XCT) and X-ray microscopy (XRM)

e-Journal of Nondestructive Testing

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e-Journal of Nondestructive Testing 2025年第2期30卷

作者： Shi, Chengnan Soete, Jeroen Janssen, Hans KU Leuven Department of Civil Engineering Building Physics and Sustainable Design Leuven3001 Belgium KU Leuven Department of Materials Engineering Structural Composites and Alloys Integrity and Nondestructive Testing Leuven3001 Belgium

The pore structure of porous building materials, with pore elements ranging from nanometer to millimeter scale, often is a crucial factor that impacts the material’s functional properties. This paper extensively characterizes the pore structure of ceramic brick, a commonly applied porous building material. To address the conflict between the field of view and resolution, an image chain with eight three-dimensional greyscale image sets is acquired through X-ray computed tomography (XCT) and X-ray microscopy (XRM), with their voxel sizes progressively spanning from nanometers to micrometers. The impact of voxel size and sample size on pore structure characterization is examined quantitatively through pore network analysis. After denoising and segmenting the acquired images, the maximal ball method is applied to extract the pore network for evaluation. This paper characterizes the pore structure of ceramic brick through the construction of the image chain. Additionally, scanning the same sample with a finer voxel size naturally captures more details, and allows the pore network extraction algorithm to better preserve pore structure. On the other hand, the impact of sample size on pore network characterization for ceramic brick is negligible if the oversized sample allows sufficient X-ray transmission. © 2025, null. All rights reserved.

关键词： Computerized tomography

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Numerically predicting seismic drift of multi-storied buildings considering impact of mat by equivalent static method based on BNBC 2020

Progress in Engineering Science

引用

Progress in engineering Science 2025年第1期2卷

作者： Haque, Md. Foisal Department of Civil Engineering International University of Business Agriculture and Technology Dhaka 1230 Bangladesh Structural and Geotechnical Expert GS Research & Design Dhaka 1230 Bangladesh

The failure of mat-founded building structure is influenced by the inter-storey drift variation during seismic excitation. For this reason, this research evaluates the nature and shape of the inter-storey drift variations of 6 and 9-storied reinforced concrete moment resisting frames by changing the mat thicknesses from the linear elastic numerical analysis by using ETABS v. 18.1.1. This finding is the new insight in this research. Several variable parameters are involved for the drift variations such as seismic zone coefficients, site classes, brick partition wall thicknesses, and response reduction factors. Field investigations at four Cities in Bangladesh have been conducted to select the site class for calculating the base shear coefficient by equivalent static procedure. The mat with sand is acted as spring that is connected to the base of the each column of the building structure. The nature and shape of the drift variation is found to be almost constant and straight according to the numerical analysis results. The validated inter-storey drift ratio is found to be (0.79–2.22) %, which may indicate a good accuracy of numerical analysis. The ranges of drift variations for 6 and 9-storied building structures are found to be (2.25–12.40) % and (2.44–17.13) %, respectively. However, this research can be extended in future by incorporating variable mat sizes, multi-layered soil, nonlinear analysis etc. © 2024 Elsevier B.V.

关键词： Bangladesh National Building Code 2020 Equivalent Static Procedure Field Investigations Finite Element-Based Software ETABS v. 18.1.1 Seismic Inter-Storey Drift

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Core-shell structured BN/SiO_(2)nanofiber membrane featuring with dual-effect thermal management and flame retardancy for extreme space thermal protection

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Science Bulletin 2025年第5期70卷 722-732页

作者： Duo Pan Ziyuan Han Junting Lei Yutao Niu Hu Liu Sunmi Shin Chuntai Liu Zhanhu Guo State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentNational Engineering Research Center for Advanced Polymer Processing TechnologyZhengzhou UniversityZhengzhou 450001China Key Laboratory of Multifunctional Nanomaterials and Smart Systems Advanced Materials DivisionSuzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhou 215123China Department of Mechanical Engineering College of Design and EngineeringNational University of SingaporeSingapore 117575Singapore Mechanical and Construction Engineering Faculty of Engineering and EnvironmentNorthumbria UniversityNewcastle Upon TyneNE18STUK

With the rapid progress of aerospace frontier engineering,the extreme space thermal environment has brought severe challenges to astronauts’space suits,putting forward higher requirements for thermal protection *** this basis,a unique core-shell structured hexagonal boron nitride(h-BN)/silicon dioxide(SiO_(2))nanofiber membrane(HS)was prepared using the coaxial electrospinning method,of which both the thermal insulation SiO_(2)nanofiber cortex and the passive radiation cooling(PRC)h-BN nanofiber core make it a promising dual-effect thermal management ***,when the amount of h-BN is 0.9 g,the resultant HS(HS0.9)exhibits astonishing low thermal conductivity of 0.026 W m−1 K−1 and high reflectivity and emissivity of exceeding 90%over an extremely wide *** expected dual-effect thermal management performance enables the HS to have an ideal cooling effect under both high sunlight intensity and strong light *** addition,HS also shows excellent flame retardant performance arising from the excellent high-temperature stability of h-BN and SiO_(2).What is more,the tensile strength of HS0.9 was also significantly increased from 0.42 to 7.2 MPa by encapsulating polyimide through vacuum ***,the research results of this work provide innovative highlights for high-temperature protection in daily life and even extreme space environments.

关键词： h-BN/SiO_(2)nanofiber membrane Core-shell structure Passive radiative cooling Thermal insulation Flame retardancy

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A structured framework for HBIM standardization: Integrating scan-to-BIM methodologies and heritage conservation standards

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Digital Applications in Archaeology and Cultural Heritage 2025年 37卷

作者： Salah, Rnin Károlyfi, Kitti Ajtayné Szép, János Géczy, Nóra Department of Structural and Geotechnical Engineering Széchenyi István University Győr H-9026 Hungary Department of Architectural Design Széchenyi István University Győr H-9026 Hungary

Heritage conservation demands innovative approaches that integrate advanced technologies with traditional principles to protect monuments and historic buildings. This research investigates the potential of Building Information Modeling (BIM) in heritage conservation, with a focus on developing and adapting workflows tailored to Heritage Building Information Modeling (HBIM). Through a systematic analysis of literature, the research highlights the adaptation of scan-to-BIM methodologies for HBIM creation and their significant role in enhancing preservation efforts. Key technologies, including laser scanning, photogrammetry, and machine learning, are discussed for their contributions to generate accurate and information-rich digital models of heritage structures. Furthermore, this work discovers critical specifications and proposes a structured framework for balancing these specifications within HBIM workflows. This framework addresses challenges such as standardization, scalability, and adaptability, which are essential for accurately capturing the complexity of heritage buildings. By examining these issues, the study identifies opportunities to improve HBIM's capability to monitor, document, and manage culturally significant assets. The findings provide a comprehensive understanding of HBIM processes and their potential to support the effective conservation of heritage. © 2025 The Authors

关键词： (AI) (HBIM) (LOA) (LOD) (LOI) Artificial intelligence Heritage Building Information Modeling Level of Accuracy Level of Detail Level of Information Scan-to-BIM

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Technological developments of amphibious aircraft designs: Research milestone and current achievement

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Curved and Layered Structures 2025年第1期12卷

作者： Putra, Ebenhaezer Candela Kristiawan Suryanto, Muhammad Ramadhani Suryanto, Suryanto Adiputra, Ristiyanto Prabowo, Aditya Rio Puryantini, Navik Carvalho, Hermes Jurkovič, Martin Imanullah, Fahmi Department of Mechanical Engineering Universitas Sebelas Maret Surakarta Indonesia Laboratory of Design and Computational Mechanics Faculty of Engineering Universitas Sebelas Maret Surakarta Indonesia Surabaya Indonesia Department of Structural Engineering Federal University of Minas Gerais Minas Gerais Belo Horizonte Brazil Department of Structural Engineering and Geotechnical University of São Paulo São Paulo Brazil Faculty of Operation and Economics of Transport and Communication University of Žilina Žilina Slovakia China Shipbuilding Industry Corporation Economic Research Center Beijing China

This study aims to examine the development of research on seaplanes and determine the innovations that have been achieved or researched. To better serve the demands of real aircraft designers, this research presented a new process for creating seaplane designs. Combining historical seaplane data with current ship and aircraft design data resulted in a new preliminary seaplane concept design. Another benefit of this design approach is transforming an existing landplane into a seaplane by adding a floating device that satisfies seaplane conversion standards. Enhancing hydrodynamic performance was the addition of a trimaran design. A retractable float device was employed to add drag reduction during flying. The trimaran idea provided superior hydrostatic stability and increased water speed, while the floats’ retractable design decreased aerodynamic drag for improved flying performance. A computational design framework is also created to assess the efficacy and performance of hydrofoils for amphibious aircraft, with a particular emphasis on water take-off performance. For validation, a comparison is made between the numerical simulations and the experiment results. The results of this study show that seaplane research over the past decade has produced several innovations, from general to detailed designs. Seaplane also has the potential to be developed in the coming years. © 2025 the author(s), published by De Gruyter.

关键词： Drag reduction

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Ductilization of 2.6-GPa alloys via short-range ordered interfaces and supranano precipitates

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Science (New York, N.Y.) 2025年第6732期387卷 401-406页

作者： Yan, Yong-Qiang Cha, Wen-Hao Liu, Sida Ma, Yan Luan, Jun-Hua Rao, Ziyuan Liu, Chang Shan, Zhi-Wei Lu, Jian Wu, Ge Center for Advancing Materials Performance from the Nanoscale (CAMP-Nano) Hysitron Applied Research Center in China (HARCC) and Center for Alloy Innovation and Design (CAID) State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University Xi'an China Laboratory for Multiscale Mechanics and Medical Science SV LAB School of Aerospace Xi'an Jiaotong University Xi'an China Faculty of Georesources and Materials Engineering RWTH Aachen University Aachen Germany Department of Materials Science and Engineering Delft University of Technology Delft Netherlands Inter-University 3D Atom Probe Tomography Unit Department of Mechanical Engineering City University of Hong Kong Hong Kong China Max Planck Institute for Sustainable Materials Düsseldorf Germany National Engineering Research Center of Light Alloy Net Forming Shanghai Jiao Tong University Shanghai China Centre for Advanced Structural Materials Department of Materials Science and Engineering City University of Hong Kong Hong Kong China

Higher strength and higher ductility are desirable for structural materials. However, ultrastrong alloys inevitably show decreased strain-hardening capacity, limiting their uniform elongation. We present a supranano (<10 nanometers) and short-range ordering design for grain interiors and grain boundary regions, respectively, in fine-grained alloys based on vanadium, cobalt, and nickel, with additions of tungsten, copper, aluminum, and boron. The pronounced grain boundary-related strengthening and ductilization mechanism is realized through segregation of the short-range ordering near the grain boundary. Furthermore, the supranano ordering with a larger size has an enhanced pinning effect for dislocations and stacking faults, multiplied and accumulated in grain interiors during plastic deformation. These mechanisms promote continuously increased flow stress until fracture of the alloy at 10% strain with 2.6-gigapascal tensile stress.

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Earthquake damage potential and critical scour depth of bridges exposed to flood and seismic hazards under lateral seismic loads

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Earthquake engineering and engineering Vibration 2015年第4期14卷 579-594页

作者： Shin-Tai Song Chun-Yao Wang Wen-Hsiu Huang Department of Civil Engineering Chung-Hsing University Structural Design Department Giant Home Engineering and Consultant

Many bridges located in seismic hazard regions suffer from serious foundation exposure caused by riverbed scour. Loss of surrounding soil significantly reduces the lateral strength of pile foundations. When the scour depth exceeds a critical level, the strength of the foundation is insufficient to withstand the imposed seismic demand, which induces the potential for unacceptable damage to the piles during an earthquake. This paper presents an analytical approach to assess the earthquake damage potential of bridges with foundation exposure and identify the critical scour depth that causes the seismic performance of a bridge to differ from the original design. The approach employs the well-accepted response spectrum analysis method to determine the maximum seismic response of a bridge. The damage potential of a bridge is assessed by comparing the imposed seismic demand with the strengths of the column and the foundation. The versatility of the analytical approach is illustrated with a numerical example and verified by the nonlinear finite element analysis. The analytical approach is also demonstrated to successfully determine the critical scour depth. Results highlight that relatively shallow scour depths can cause foundation damage during an earthquake, even for bridges designed to provide satisfactory seismic performance.

关键词： soil-structure interaction seismic analysis bridge pile foundation scour

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