Structural Failure of Buildings: Issues and Challenges
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Simplified Method of Applying Loads to Flat Slab Floor Structural Model
MATEC Web of Conferences 219, 03002 (2018) https://doi.org/10.1051/matecconf/201821903002 BalCon 2018 Simplified method of applying loads to flat slab floor structural model Maciej Tomasz Solarczyk1,*, and Andrzej Ambroziak1 1Gdańsk University of Technology, Faculty of Civil and Environmental Engineering, Narutowicza 11/12, 80-233 Gdańsk, Poland Abstract. The article analyses the impact of the live load position on the surface of a reinforced concrete flat slab floor of 32.0 m × 28.8 m. Four variants of a live load position are investigated: located on the entire concrete slab, set in a chessboard pattern, applied by bands and imposed separately in each of the slab panels. Conclusions are drawn upon differences in bending moments, the time of calculation and the size of output files. The problems in the interpretation of results are presented too. A procedure is presented to model the reinforced concrete structures in computational programs. The recommendations of the Eurocodes are presented regarding to load combinations in the Ultimate Limit State (ULS). Convergence analysis of the finite element mesh is carried out to verify the obtained results. The law status on the implementation of the Building Information Modelling (BIM) technology in Poland points out significant time savings in the application of this technology. 1 Introduction Structural design is generally based on virtual mapping of a real object. The designer is supported by a number of computational tools to complete the task. A widespread automation of design works makes it available for the engineers with little experience. It should be emphasized that the results of numerical analysis should be permanently and critically assessed by the designer after computations. -
CHAPTER TWO - Static Aeroelasticity – Unswept Wing Structural Loads and Performance 21 2.1 Background
Static aeroelasticity – structural loads and performance CHAPTER TWO - Static Aeroelasticity – Unswept wing structural loads and performance 21 2.1 Background ........................................................................................................................... 21 2.1.2 Scope and purpose ....................................................................................................................... 21 2.1.2 The structures enterprise and its relation to aeroelasticity ............................................................ 22 2.1.3 The evolution of aircraft wing structures-form follows function ................................................ 24 2.2 Analytical modeling............................................................................................................... 30 2.2.1 The typical section, the flying door and Rayleigh-Ritz idealizations ................................................ 31 2.2.2 – Functional diagrams and operators – modeling the aeroelastic feedback process ....................... 33 2.3 Matrix structural analysis – stiffness matrices and strain energy .......................................... 34 2.4 An example - Construction of a structural stiffness matrix – the shear center concept ........ 38 2.5 Subsonic aerodynamics - fundamentals ................................................................................ 40 2.5.1 Reference points – the center of pressure..................................................................................... 44 2.5.2 A different -
Risk Perception and Coping Behavior of Construction Workers on Occupational Health Risks—A Case Study of Nanjing, China
International Journal of Environmental Research and Public Health Article Risk Perception and Coping Behavior of Construction Workers on Occupational Health Risks—A Case Study of Nanjing, China Hui Liu 1, Jie Li 2 , Hongyang Li 3,4,5, He Li 6, Peng Mao 1,* and Jingfeng Yuan 7 1 Department of Construction Management, College of Civil Engineering, Nanjing Forestry University, Nanjing 210037, China; [email protected] 2 School of Civil and Transportation Engineering, Shenzhen University, Shenzhen 518060, China; [email protected] 3 Business School, Hohai University, Nanjing 211100, China; [email protected] 4 School of Civil Engineering and Transportation, South China University of Technology, Guangzhou 510641, China 5 State Key Laboratory of Subtropical Building Science, South China University of Technology, Guangzhou 510641, China 6 College of Civil Engineering, Hunan University, Changsha 410082, China; [email protected] 7 Department of Construction and Real Estate, School of Civil Engineering, Southeast University, Nanjing 210096, China; [email protected] * Correspondence: [email protected]; Tel.: +86-138-0517-1820 Abstract: To reduce harm caused by occupational health risks of construction workers exposed to working environments, especially those for interior decoration, it is crucial for them to actively recognize and prevent these risks. Therefore, how to improve their occupational health risks percep- tion and regulate their coping behaviors should be of great concern. However, most prior studies target construction worker safety, and little research focuses on risk analysis from the psychological Citation: Liu, H.; Li, J.; Li, H.; Li, H.; level of workers. Hence, construction workers’ occupational health risk perception level and coping Mao, P.; Yuan, J. -
Guide for Load and Resistance Factor Design (LRFD) Criteria for Offshore Structures
Guide for Load and Resistance Factor Design (LRFD) Criteria for Offshore Structures GUIDE FOR LOAD AND RESISTANCE FACTOR DESIGN (LRFD) CRITERIA FOR OFFSHORE STRUCTURES JULY 2016 American Bureau of Shipping Incorporated by Act of Legislature of the State of New York 1862 2016 American Bureau of Shipping. All rights reserved. ABS Plaza 16855 Northchase Drive Houston, TX 77060 USA Foreword Foreword This Guide provides structural design criteria in a Load and Resistance Factor Design (LRFD) format for specific types of Mobile Offshore Drilling Units (MODUs), Floating Production Installations (FPIs) and Mobile Offshore Units (MOUs). The LRFD structural design criteria in this Guide can be used as an alternative to those affected criteria in Part 3 of the ABS Rules for Building and Classing Mobile Offshore Drilling Units and Part 5B of the ABS Rules for Building and Classing Floating Production Installations, where the criteria are presented in the Working Stress Design (WSD) format, also known as the Allowable Stress (or Strength) Design (ASD) format. This Guide becomes effective on the first day of the month of publication. Users are advised to check periodically on the ABS website www.eagle.org to verify that this version of this Guide is the most current. We welcome your feedback. Comments or suggestions can be sent electronically by email to [email protected]. ii ABS GUIDE FOR LOAD AND RESISTANCE FACTOR DESIGN (LRFD) CRITERIA FOR OFFSHORE STRUCTURES . 2016 Table of Contents GUIDE FOR LOAD AND RESISTANCE FACTOR DESIGN (LRFD) CRITERIA FOR OFFSHORE STRUCTURES CONTENTS CHAPTER 1 General .................................................................................................... 1 Section 1 Introduction ............................................................................ 2 Section 2 Principles of the LRFD Method ............................................. -
Deflection-Based Aircraft Structural Loads Estimation with Comparison to Flight
Deflection-Based Aircraft Structural Loads Estimation With Comparison to Flight Andrew M. Lizotte* and William A. Lokos† NASA Dryden Flight Research Center, Edwards, California, 93523-0273 Traditional techniques in structural load measurement entail the correlation of a known load with strain-gage output from the individual components of a structure or machine. The use of strain gages has proved successful and is considered the standard approach for load measurement. However, remotely measuring aerodynamic loads using deflection measurement systems to determine aeroelastic deformation as a substitute to strain gages may yield lower testing costs while improving aircraft performance through reduced instrumentation weight. With a reliable strain and structural deformation measurement system this technique was examined. The objective of this study was to explore the utility of a deflection-based load estimation, using the active aeroelastic wing F/A-18 aircraft. Calibration data from ground tests performed on the aircraft were used to derive left wing-root and wing-fold bending-moment and torque load equations based on strain gages, however, for this study, point deflections were used to derive deflection-based load equations. Comparisons between the strain-gage and deflection-based methods are presented. Flight data from the phase-1 active aeroelastic wing flight program were used to validate the deflection-based load estimation method. Flight validation revealed a strong bending-moment correlation and slightly weaker torque correlation. -
“Linear Buckling” Analysis Branch
Appendix A Eigenvalue Buckling Analysis 16.0 Release Introduction to ANSYS Mechanical 1 © 2015 ANSYS, Inc. February 27, 2015 Chapter Overview In this Appendix, performing an eigenvalue buckling analysis in Mechanical will be covered. Mechanical enables you to link the Eigenvalue Buckling analysis to a nonlinear Static Structural analysis that can include all types of nonlinearities. This will not be covered in this section. We will focused on Linear buckling. Contents: A. Background On Buckling B. Buckling Analysis Procedure C. Workshop AppA-1 2 © 2015 ANSYS, Inc. February 27, 2015 A. Background on Buckling Many structures require an evaluation of their structural stability. Thin columns, compression members, and vacuum tanks are all examples of structures where stability considerations are important. At the onset of instability (buckling) a structure will have a very large change in displacement {x} under essentially no change in the load (beyond a small load perturbation). F F Stable Unstable 3 © 2015 ANSYS, Inc. February 27, 2015 … Background on Buckling Eigenvalue or linear buckling analysis predicts the theoretical buckling strength of an ideal linear elastic structure. This method corresponds to the textbook approach of linear elastic buckling analysis. • The eigenvalue buckling solution of a Euler column will match the classical Euler solution. Imperfections and nonlinear behaviors prevent most real world structures from achieving their theoretical elastic buckling strength. Linear buckling generally yields unconservative results -
Arxiv:2102.13492V2 [Physics.Comp-Ph] 3 Mar 2021
Local micromorphic non-affine anisotropy for materials incorporating elastically bonded fibers Sebastian Skatulla1,2, Carlo Sansour3, and Georges Limbert4,5 1Department of Civil Engineering, University of Cape Town, South Africa 2Center for Research in Computational and Applied Mechanics, University of Cape Town, South Africa 3Department of Mathematics, Bethlehem University, Bethlehem, Palestine 4National Centre for Advanced Tribology at Southampton (nCATS) and Bioengineering Science Research Group, Department of Mechanical Engineering, Faculty of Engineering and Physical Sciences, University of Southampton, Southampton SO17 1BJ, UK 5Laboratory of Biomechanics and Mechanobiology, Division of Biomedical Engineering, Department of Human Biology, Faculty of Health Sciences, University of Cape Town, Observatory 7935, Cape Town, South Africa March 4, 2021 Abstract There has been increasing experimental evidence of non-affine elas- tic deformation mechanisms in biological soft tissues. These observations call for novel constitutive models which are able to describe the dom- inant underlying micro-structural kinematics aspects, in particular rel- ative motion characteristics of different phases. This paper proposes a flexible and modular framework based on a micromorphic continuum en- compassing matrix and fiber phases. It features in addition to the dis- placement field so-called director fields which can independently deform and intrinsically carry orientational information. Accordingly, the fibrous arXiv:2102.13492v2 [physics.comp-ph] 3 Mar 2021 constituents can be naturally associated with the micromorphic directors and their non-affine motion within the bulk material can be efficiently captured. Furthermore, constitutive relations can be formulated based on kinematics quantities specifically linked to the material response of the matrix, the fibres and their mutual interactions. Associated stress quantities are naturally derived from a micromorphic variational princi- ple featuring dedicated governing equations for displacement and director 1 fields. -
Structural Components, Lifting Mechanism, Crane Control Project Has Been Established with a View to Remove the Need to Have Workers in High Places
Impact Objectives • Increase construction worker safety using automated technologies • Develop autonomous erection systems that can be controlled remotely Improving construction worker safety Professors Shih-Chung Kang and Chia-Ming Chang and PhD candidates Yao-Yu Yang and Ci-Jyun Liang discuss their pioneering efforts to remove the need for human beings to work in high, potentially dangerous places structural engineering to construction, in particular automated construction methods. Could you introduce AutoCon in layman’s terms? Professor Shih-Chung Professor Chia-Ming Yao-Yu Yang Ci-Jyun Liang YY: AutoCon is an abbreviation for Kang Chang autonomous connector. This is a connector design that is customised for autonomous Could you begin by providing a brief Laboratories. My research interests include construction. Conventional automation overview of your respective research data visualisation, computer vision, for construction usually involves inventing interests and aims? smart monitoring device, and robotics in machines that complete work initiated by construction. humans. In contrast, AutoCon is a design, SK: I have a PhD from Stanford University, but also a concept, that tries to think about USA, and am now a Professor in the CL: I am currently a graduate student at the automation for construction. It begins Department of Civil Engineering in National the Robotics Institute in the University by redesigning the very basic element of the Taiwan University (NTU). My research of Michigan, USA. I am working with structure – the structural connector. focuses on advanced visual and robotics Professor Vineet Kamat in the Laboratory tools for engineering purposes, with a view to for Interactive Visualisation in Engineering Why did your team opt to employ a ‘bottom- eliminating the need for workers to be in high (LIVE). -
Identifying Determinants of Construction Worker Performance on Construction Sites: a Literature Review
International Journal of Innovation, Management and Technology, Vol. 8, No. 1, February 2017 Identifying Determinants of Construction Worker Performance on Construction Sites: A Literature Review Chioma S. Okoro, Innocent Musonda, and Justus Agumba executing the processes and activities in construction, they Abstract—The construction industry in many developed and have a significant influence on labour productivity and it is developing countries suffers from delays and cost overruns due important to know what they need and what affects their to poor labour productivity. This paper aims to identify performance [9]. Continuous attention to the determinants determinants of construction workers’ performance on of construction workers’ performance is vital if maximal construction sites in terms of ratio of output to input (productivity). A literature review of relevant literature was productivity in the industry is desired. conducted from journals and conference proceedings and Research has been conducted on the determinants of theses, based on international and South African context. The labour productivity. Ref. [10] used a Health and Labour study identified that wages/salary, working time, financial Questionnaire and a Quantity and Quality instrument to initiatives, communication, nutrition, fatigue and health, measure the effect of health status of workers (including adequacy of plans and specifications, availability of industrial and construction workers). Reference [11] consumables, education and training on the job, management dynamics, safety measures and proper work planning explored project managers’ perceptions (in Uganda) on the determine construction workers’ performance on construction labour productivity factors in relation to time, cost and sites. The findings of the present study could help constitution quality only. Ref. -
Employment in the Construction Industry in the Past 30 Years
TMCIT/2001 INTERNATIONAL LABOUR ORGANIZATION The construction industry in the twenty- first century: Its image, employment prospects and skill requirements Tripartite Meeting on the Construction Industry in the Twenty-first Century: Its Image, Employment Prospects and Skill Requirements Geneva, 2001 INTERNATIONAL LABOUR OFFICE GENEVA Contents Introduction........................................................................................................................................ 1 The context ................................................................................................................................ 1 Background to the Meeting........................................................................................................ 2 Outline of the report................................................................................................................... 3 1. Construction output and employment: The global picture......................................................... 5 1.1. Output and employment at the end of the twentieth century........................................... 5 1.2. Global trends in output and employment......................................................................... 8 1.3. The role of construction employment and characteristics of the workforce.................... 11 1.4. Construction in the eyes of the workforce....................................................................... 13 2. Recent changes in employment relationships and industrial structure ..................................... -
Construction Workers' Health and Safety During Post Disaster Reconstruction Phase: a Case Study in Nepal
Florida International University FIU Digital Commons FIU Electronic Theses and Dissertations University Graduate School 3-29-2019 Construction Workers' Health and Safety During Post Disaster Reconstruction Phase: A Case Study in Nepal S M Jamil Uddin Florida International University, [email protected] Follow this and additional works at: https://digitalcommons.fiu.edu/etd Part of the Construction Engineering and Management Commons Recommended Citation Uddin, S M Jamil, "Construction Workers' Health and Safety During Post Disaster Reconstruction Phase: A Case Study in Nepal" (2019). FIU Electronic Theses and Dissertations. 4011. https://digitalcommons.fiu.edu/etd/4011 This work is brought to you for free and open access by the University Graduate School at FIU Digital Commons. It has been accepted for inclusion in FIU Electronic Theses and Dissertations by an authorized administrator of FIU Digital Commons. For more information, please contact [email protected]. FLORIDA INTERNATI ONAL UNIVERSITY Miami, Florida CONSTRUCTION WORKERS’ HEALTH A ND SAFETY DURING POST DISASTER RECONSTRUCTION PHASE: A CASE STUDY IN NEPAL A thesis submitted in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE in CONSTRUCTION M ANAGEMENT by S M Jamil Uddin 2019 To: Dean John L. Volakis College of Engineering and Computing This thesis, written by S M Jamil Uddin, and entitled Construction Workers’ Health and Safety during Post Disaster Reconstruction Phase: A Case Study in Nepal, having been approved in respect to style and intellectual content, is referred to you for judgment. We have read this thesis and recommend that it be approved. _______________________________________ N. Emel Ganapati _______________________________________ Jose A. -
APPENDIX a Working Plan
APPENDIX A Working Plan CVO\081750013 Appendix A: Working Plan This Working Plan summarizes the tasks that will be carried out to complete the Seismic Design and Analysis of Retaining Walls, Buried Structures, Slopes, and Embankments. The first section in this Working Plan provides an overview of the philosophy and research work that will be implemented to meet the goals of the research program. The following sections of the Working Plan then provide detailed discussions of Project approach. This Working Plan is based on the CH2M HILL proposal submitted to NCHRP in early November of 2003 with modifications summarized in Attachment 2 of CH2M HILL’s letter to Dr. Robert Reilly of the Transportation Research Board dated January 13, 2004. A.1 Overview of Working Plan The objective of the NCHRP Project 12-70 (Project) will be to develop analytical methods and recommended load and resistance factor design (LRFD) specifications for the design of retaining walls, slopes and embankments, and buried structures. The Specifications will be consistent with the philosophy and format of the AASHTO LRFD Bridge Design Specifications and the seismic provisions for highway bridges. A two-phased approach will be taken for this Project: (1) literature reviews and analytical developments will occur in Phase 1; and (2) LRFD specifications, commentary, and examples will be prepared in Phase 2. When addressing the buried structure component of this project, vehicular tunnels will not be included. The planned approach for the Project will consider the AASHTO LRFD Bridge Design Specifications requirements which state that “Bridges shall be designed for specified limit states to achieve the objectives of constructibility, safety, and serviceability, with due regard to issues of inspectibility, economy, and aesthetics….” In the LRFD design procedure, margins of safety are incorporated through load (γ) factors and performance (or resistance, φ) factors.