Accuracy of a Simplified Analysis Model for Modern Skyscrapers

Total Page:16

File Type:pdf, Size:1020Kb

Accuracy of a Simplified Analysis Model for Modern Skyscrapers Brigham Young University BYU ScholarsArchive Theses and Dissertations 2013-06-11 Accuracy of a Simplified Analysis Model for Modern Skyscrapers Jacob Scott Lee Brigham Young University - Provo Follow this and additional works at: https://scholarsarchive.byu.edu/etd Part of the Civil and Environmental Engineering Commons BYU ScholarsArchive Citation Lee, Jacob Scott, "Accuracy of a Simplified Analysis Model for Modern Skyscrapers" (2013). Theses and Dissertations. 4055. https://scholarsarchive.byu.edu/etd/4055 This Thesis is brought to you for free and open access by BYU ScholarsArchive. It has been accepted for inclusion in Theses and Dissertations by an authorized administrator of BYU ScholarsArchive. For more information, please contact [email protected], [email protected]. Accuracy of a Simplified Analysis Model for Modern Skyscrapers Jacob S. Lee A thesis submitted to the faculty of Brigham Young University in partial fulfillment of the requirements for the degree of Master of Science Richard J. Balling, Chair Paul W. Richards Fernando S. Fonseca Department of Civil and Environmental Engineering Brigham Young University June 2013 Copyright © 2013 Jacob S. Lee All Rights Reserved ABSTRACT Accuracy of a Simplified Analysis Model for Modern Skyscrapers Jacob S. Lee Department of Civil and Environmental Engineering, BYU Master of Science A new simplified skyscraper analysis model (SSAM) was developed and implemented in a spreadsheet to be used for preliminary skyscraper design and teaching purposes. The SSAM predicts linear and nonlinear response to gravity, wind, and seismic loading of "modern" skyscrapers which involve a core, megacolumns, outrigger trusses, belt trusses, and diagonals. The SSAM may be classified as a discrete method that constructs a reduced system stiffness matrix involving selected degrees of freedom (DOF's). The steps in the SSAM consist of: 1) determination of megacolumn areas, 2) construction of stiffness matrix, 3) calculation of lateral forces and displacements, and 4) calculation of stresses. Seven configurations of a generic skyscraper were used to compare the accuracy of the SSAM against a space frame finite element model. The SSAM was able to predict the existence of points of contraflexure in the deflected shape which are known to exist in modern skyscrapers. The accuracy of the SSAM was found to be very good for displacements (translations and rotations), and reasonably good for stress in configurations that exclude diagonals. The speed of execution, data preparation, data extraction, and optimization were found to be much faster with the SSAM than with general space frame finite element programs. Keywords: Jacob S. Lee, skyscraper, structural analysis, optimization, preliminary design ACKNOWLEDGEMENTS I wish to express my sincere appreciation and thanks to my advisor, Dr. Richard J. Balling, for his help and dedication that went into our research. I am grateful for his motivation and encouragement in stretching my mind in ways I never thought possible. I was blessed with the opportunity he gave me to explore an area of structural engineering that inspires me and share that experience alongside him. I am indeed indebted to him for making it possible to travel to China to study the skyscrapers there and collaborate with the engineers behind their designs as part of his Megastructures class. That unforgettable experience has given me a wider perspective of what structural engineering has to offer and excites me about my future career aspirations in engineering. I would also like to thank my committee members, Dr. Paul W. Richards and Dr. Fernando S. Fonseca, who have truly been inspirational professors to me in my academic life at BYU. I would like to thank my family and friends who have supported me throughout this endeavor and my graduate degree, and who have instilled in me the values of one who strives to emulate the pure love of Christ. I would also like to thank my fellow colleagues for their hard work and insight during this project. TABLE OF CONTENTS LIST OF TABLES ...................................................................................................................... vii LIST OF FIGURES ...................................................................................................................... x 1 Introduction ........................................................................................................................... 1 2 Literature review................................................................................................................. 13 2.1 Continuum Methods for Low/Medium-Rise Buildings ................................................ 13 2.2 Continuum Method for Framed Tubes ......................................................................... 16 2.3 Inherent Problems with Continuum Methods ............................................................... 17 2.4 Discrete Outrigger Methods .......................................................................................... 20 2.5 Discrete Substructuring Methods .................................................................................. 22 3 Simplified Skyscraper Analysis Model ............................................................................. 24 3.1 Determination of Megacolumn Areas ........................................................................... 24 3.2 Construction of the Stiffness Matrix ............................................................................. 27 3.3 Calculation of Lateral Forces/Displacements ............................................................... 39 3.4 Calculation of Stresses .................................................................................................. 44 3.5 Rapid Trial-and-Error Optimization ............................................................................. 52 4 Space frame model .............................................................................................................. 54 4.1 Nodes ............................................................................................................................ 54 4.2 Members ....................................................................................................................... 55 4.3 Supports ........................................................................................................................ 58 4.4 Loads ............................................................................................................................. 59 4.5 Output ........................................................................................................................... 59 5 Results .................................................................................................................................. 60 5.1 Configuration #1 – core+megacolumns ........................................................................ 61 v 5.2 Configuration #2 – core+megacolumns+outriggers ..................................................... 65 5.3 Configuration #3 – core+megacolumns+belts .............................................................. 68 5.4 Configuration #4 – core+megacolumns+diagonals ...................................................... 72 5.5 Configuration #5 – core+megacolumns+outriggers+belts ........................................... 76 5.6 Configuration #6 – core+megacolumns+outriggers+belts+diagonals .......................... 81 5.7 Configuration #7 – core+megacolumns+outirgger at one level only ........................... 85 6 Conclusions .......................................................................................................................... 89 REFERENCES ............................................................................................................................. 91 APPENDIX A. SSAM Excel Spreadsheet (Configuration #6) ............................................. 95 vi LIST OF TABLES Table 3-1: Stiffness matrix - contribution of the core and megacolumns ..............................29 Table 3-2: Stiffness matrix - contribution of outriggers ........................................................32 Table 3-3: Stiffness matrix - contribution of the belt trusses .................................................35 Table 3-4: Stiffness matrix - contribution of diagonals .........................................................37 Table 5-1: Configuration #1 - design variables and calculated megacolumn areas ..............61 Table 5-2: Configuration #1 - lateral core translation (m) .....................................................62 Table 5-3: Configuration #1 - core rotation (rad) ..................................................................62 Table 5-4: Configuration #1 - vertical megacolumn translation minus vertical core translation .............................................................................................................63 Table 5-5: Configuration #1 - core stress (KPa) ....................................................................63 Table 5-6: Configuration #1 - megacolumn stress (KPa) ......................................................64 Table 5-7: Configuration #2 - design variables and calculated megacolumn areas ..............65 Table 5-8: Configuration #2 - lateral core translation (m) .....................................................65 Table 5-9: Configuration #2 - core rotation (rad) ..................................................................65 Table 5-10:
Recommended publications
  • Lbbert Wayne Wamer a Thesis Presented to the Graduate
    I AN ANALYSIS OF MULTIPLE USE BUILDING; by lbbert Wayne Wamer A Thesis Presented to the Graduate Committee of Lehigh University in Candidacy for the Degree of Master of Science in Civil Engineering Lehigh University 1982 TABLE OF CCNI'ENTS ABSI'RACI' 1 1. INTRODlCI'ICN 2 2. THE CGJCEPr OF A MULTI-USE BUILDING 3 3. HI8rORY AND GRami OF MULTI-USE BUIIDINCS 6 4. WHY MULTI-USE BUIIDINCS ARE PRACTICAL 11 4.1 CGVNI'GJN REJUVINATICN 11 4. 2 EN'ERGY SAVIN CS 11 4.3 CRIME PREVENTIOO 12 4. 4 VERI'ICAL CANYOO EFFECT 12 4. 5 OVEOCRO'IDING 13 5. DESHN CHARACTERisriCS OF MULTI-USE BUILDINCS 15 5 .1 srRlCI'URAL SYSI'EMS 15 5. 2 AOCHITECI'URAL CHARACTERisriCS 18 5. 3 ELEVATOR CHARACTERisriCS 19 6. PSYCHOI..OCICAL ASPECTS 21 7. CASE srUDIES 24 7 .1 JOHN HANCOCK CENTER 24 7 • 2 WATER TOiVER PlACE 25 7. 3 CITICORP CENTER 27 8. SUMMARY 29 9. GLOSSARY 31 10. TABLES 33 11. FIGJRES 41 12. REFERENCES 59 VITA 63 iii ACKNCMLEI)(}IIENTS The author would like to express his appreciation to Dr. Lynn S. Beedle for the supervision of this project and review of this manuscript. Research for this thesis was carried out at the Fritz Engineering Laboratory Library, Mart Science and Engineering Library, and Lindennan Library. The thesis is needed to partially fulfill degree requirenents in Civil Engineering. Dr. Lynn S. Beedle is the Director of Fritz Laboratory and Dr. David VanHom is the Chainnan of the Department of Civil Engineering. The author wishes to thank Betty Sumners, I:olores Rice, and Estella Brueningsen, who are staff menbers in Fritz Lab, for their help in locating infonnation and references.
    [Show full text]
  • Braced Tube Structural System: a Review
    International Journal of Scientific & Engineering Research, Volume 6, Issue 12, December-2015 484 ISSN 2229-5518 Braced tube Structural System: A Review Hardik J. Patel Prof. A. R. Darji PROF. (DR.). K. B. PARIKH PG Student, M.E. Structure M.E. Structure engineer,, Assistant Head of Department, engineer Professor Government Engineering Government Engineering College, Government Engineering College, College, Dahod, Gujarat, Dahod, Gujarat, India. Applied Mechanics Department, India. Abstract: The advanced construction technologies, evolution of efficient structural system, necessity of vertical growth because of scarcity of urban land and rapidly increasing population caused the development of the high rise buildings all over the world. Lateral loads i.e. earthquake loads and wind loads requires special attention in design of high rise buildings along with gravitational loading. Lateral loads can be taken care by interior structural system or exterior structural system. Generally shear wall core, braced frame and their combination with other frames are interior structural systems where lateral load is borne by centrally located structural elements. While framed tube, braced tube structural system bear lateral loads by the elements provided on periphery of the buildings. It is very much important that the selected structural system must be optimized and should utilize structural elements effectively while satisfying design requirements. In the past decades, the Braced tube structural system is widely adopted and used for the construction of tall steel buildings due to its structural efficiency and aesthetic potential provided by the unique geometric configuration of the system. Compared to closely-spaced vertical columns in framed tube, Braced tube structural system consists of widely spaced column with inclined X- brace members on the exterior surface of building.
    [Show full text]
  • Structural Development of Skyscrapers
    STRUCTURAL DEVELOPMENT OF SKYSCRAPERS 1ABHISHEK GUPTA, 2S.M. GUPTA 1,2NIT KURUKSHETRA, HARYANA, INDIA E-mail: [email protected], [email protected] Abstract- This paper presents a review on the evolution of the structural system of skyscrapers from earlier to the modern and the effects of this on the society and environment Keywords- Skyscrapper/Tall Buildings, Height Premium, Internal, external and hybrid structural system, Building Loads, Shear Walls, lateral rigidity, Lateral Sway, Floor Vibration I. INTRODUCTION iron. The inventor Henry Bessemer took out a patent on the process in 1855. Tall buildings emerged in the late nineteenth century In 1857, Elisha Otis and the Otis Elevator Company in the United States of America. They constituted a began manufacturing passenger elevators. Invention so-called “American Building Type,” meaning that of Elevator allowed vertical transportation of people most important tall buildings were built in the U.S.A. and goods without stair Today, however, they are a worldwide architectural Chicago is the birthplace of the skyscraper The Home phenomenon. Many tall buildings are built Insurance building (1885) in Chicago, (ten storied worldwide, especially in Asian countries, such as with 42 meter in height) is generally referred as the China, Korea, Japan, and Malaysia. first high rise building (Architect :William Jenney) The Home Insurance Building was built followed by The distribution of tall buildings has changed the Great Chicago Fire, 1871 radically with Asia now having the largest share with • The physical envelope of construction was 38%, and North America’s at 22%(Fig. 1). This data traditional load-bearing system. demonstrates the rapid growth of tall building • Thick masonry external walls creates comfortable construction in Asian while North American indoor thermal environment construction has slowed.
    [Show full text]
  • Burj Khalifa Tower
    Burj Khalifa Tower The tallest structure in the world, standing at 2,722 ft (830 meters), just over 1/2 mile high, Burj Khalifa (Khalifa Tower) opened in 2010 as a centerpiece building in a large-scale, mixed-use development called Downtown Dubai. The building originally referred to as Dubai Tower was renamed in honor of the president of the United Arab Emirates, Khalifa bin Zayed Al Nahyan. Burj Khalifa Dubai, United Arab Emirates Architecture Style Modern Skyscraper | Neo-Futurism Glass, Steel, Aluminum & Reinforced Concrete Prominent Architecture Features Y-Shaped Floor Plan Maximizes Window Perimeter Areas for residential and hotel space Buttressed central core and wing design to support the height of the building 27 setbacks in a spiraling pattern Main Structure 430,000 cubic yards reinforced concrete and 61,000 tons rebar Foundation - 59,000 cubic yards concrete and 192 piles 164 ft (50 m) deep Highly compartmentalized, pressurized refuge floors for life safety Facade Aluminum and textured stainless steel spandrel panels with low-E glass Vertical polished stainless steel fins Observation Deck - 148th Floor PROJECT SUMMARY Project Description Burj Kahlifa, the tallest building in the world, has redefined the possibilities in the design, engineering, and construction of mega-tall buildings. Incorporating periodic setbacks at the ends of each wing, the tower tapers in an upward spiraling pattern that decreases is mass as the height of the tower increases. The building’s design included multiple wind tunnel tests and design adjustments to develop optimum performance relative to wind and natural forces. The building serves as a model for the concept of future, compact, livable, urban centers with direct connections to mass transit systems.
    [Show full text]
  • Construction History of the Composite Framed Tube Structural System
    Proceedings of the First International Congress on Construction History, Madrid, 20th-24th January 2003, ed. S. Huerta, Madrid: I. Juan de Herrera, SEdHC, ETSAM, A. E. Benvenuto, COAM, F. Dragados, 2003. Construction history of the composite framed tube structural system Richard A. Ellis David P. Billington This paper examines the construction history of tall primary lateral structural system. As a result, the building s designed during the latter portion of the potential applications for composite construction are twentieth century. Fazlur Khan was able to capitalize numerous, especially with the renewed awareness of on the inherent strengths of steel and concrete by fire protection concems in high-rise structures. using them in conjunction with a framed tube system. Study of such innovations allows us to see how This idea involves a novel construction process, they came into being, how individual engineers which takes advantage of the virtues of structural contributed to their success, and how the local steel and reinforced concrete. Early applications of construction constraints stimulated the search for this system in the mid-1960's were in the 35-story such new ideas. Gateway III Building in Chicago, Illinois and the 25 story CDC Building in Houston, Texas. Composite construction is now being used more frequently in the INTRODUCTlON design of high rise buildings. This paper will look closely at the construction history of the 52-story One Born in Dacca, Bangladesh, Fazlur Rahman Khan Shell Square Building in New Orleans, which was received his Bachelor of Engineering degree from the completed in 1971 and still stands as the tallest University of Dacca.
    [Show full text]
  • The-Hows-Whats-And-Wows-Of-Willis
    There are enough impressive facts about the When you get back to your school, we hope Willis Tower to make even the most worldly your students will send us photos or write or among us say, “Wow!” So many things at the create artwork about their experiences and Willis Tower can be described by a share them with us (via email or the mailing superlative: biggest, fastest, and longest. But address at the end of this guide). there is more to the building than all these “wows”: 1,450 sky-scraping, cloud-bumping One photo will be selected as the “Photo of feet of glass and steel, 43,000 miles of the Day” and displayed on our Skydeck telephone cable, 25,000 miles of plumbing, monitors for all to see. Artwork and writing 4.56 million square feet of floor space and a will posted on bulletin boards in the view of four states. lunchroom area. We would also love to have you and your students post you Skydeck Behind the “wows” are lots of “hows” and Chicago photos to the Skydeck Chicago pages “whats” for you and your students to on Facebook, Instagram, and Twitter. explore. In this guide you will be introduced to the building—its beginnings as the Sears As you get ready for your trip, please call us Tower and its design, construction and place with any questions at (312) 875-9447. We aim in the pantheon of skyscrapers. Its name to make your visit your best school trip ever. was recently changed to the Willis Tower, proudly reflecting the name of the global insurance broker who makes the Tower its Chicago home.
    [Show full text]
  • Fazlur R. Khan Lecture
    FAZLUR R. KHAN LECTURE 1 Life-Cycle and Sustainability of Civil Infrastructure Systems – Strauss, Frangopol & Bergmeister (Eds) © 2013 Taylor & Francis Group, London, ISBN 978-0-415-62126-7 Fazlur Khan’s legacy: Towers of the future M. Sarkisian Skidmore, Owings & Merrill LLP, San Francisco, USA ABSTRACT: Dr. Khan’s contributions to the design of tall buildings have had a profound impact on the pro- fession. Kahn had a unique understanding of forces, materials, behavior, as well as art, literature, and archi- tecture. Long before there was widespread focus on environmental issues, Kahn’s designs promoted structur- al efficiency and minimizing the use of materials resulting in the least carbon emission impact on the environment. Kahn was interested in the performance of structural systems over an expected life; recognizing a building’s life -cycle and issues of abnormal loading demands, he developed concepts to apply to severe wind environments as well as early concepts of seismic isolation of structures. These system ideas have led to the development of other concepts which have yielded buildings much taller than those considered by Kahn. His ideas have inspired others to expand the possibilities in tall building design, life-cycle engineering and the effects of the structures on the environment. However, the offer was subsequently withdrawn and he went on to become an Executive Engineer with 1 INTRODUCTION the Karachi Development Authority. Because he felt that his technical abilities where not fully uti- Inquisitive as a child, Fazlur Rahman Kahn was in- lized, Kahn returned to SOM in 1960 where he spent terested in form and how forms could be made.
    [Show full text]
  • Economics Planning of Super Tall Buildings in Asia Pacific Cities
    Economics Planning of Super Tall Buildings in Asia Pacific Cities Dr Paul H K HO, Hong Kong SAR, China Key words: economics planning, super tall building, Asia Pacific SUMMARY The purpose of this paper is to study the economics planning of super tall office buildings in Asia Pacific cities. This study is based on the case study of the Asia Pacific’s 10 tallest buildings which are distributed over six major cities. All are landmark buildings with similar functions. From the analysis of the collected data, the floor plate of these buildings is comparatively large, thus achieving a fairly high lettable to gross floor ratio of about 80% and low wall to floor area ratio of about 0.33. The most common lease span is approximately 12m with column-free between its service core and exterior window. The most common floor-to-floor height is about 4.0m. Square or similar plan is the most common geometry in super tall buildings since this geometry offers the same stiffness in both directions against lateral wind forces. Typically the building is in form of a large podium at lower levels with a setback in the overall floor plan dimension in the main tower and a slightly tapered shape at its top floors. The central core approach in which the core is designed as a structural element to provide stability is commonly used in super tall buildings. By using slip-form or jump-form techniques, a 3 to 4-day cycle is achievable for core wall construction which is similar to steel construction.
    [Show full text]
  • Signature Redacted Department of Civil and Environmental Engineering May 21, 2015
    TRENDS AND INNOVATIONS IN HIGH-RISE BUILDINGS OVER THE PAST DECADE ARCHIVES 1 by MASSACM I 1TT;r OF 1*KCHN0L0LGY Wenjia Gu JUL 02 2015 B.S. Civil Engineering University of Illinois at Urbana-Champaign, 2014 LIBRAR IES SUBMITTED TO THE DEPARTMENT OF CIVIL AND ENVIRONMENTAL ENGINEERING IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF ENGINEERING IN CIVIL ENGINEERING AT THE MASSACHUSETTS INSTITUTE OF TECHNOLOGY JUNE 2015 C2015 Wenjia Gu. All rights reserved. The author hereby grants to MIT permission to reproduce and to distribute publicly paper and electronic copies of this thesis document in whole or in part in any medium now known of hereafter created. Signature of Author: Signature redacted Department of Civil and Environmental Engineering May 21, 2015 Certified by: Signature redacted ( Jerome Connor Professor of Civil and Environmental Engineering Thesis Supervisor Accepted bv: Signature redacted ?'Hei4 Nepf Donald and Martha Harleman Professor of Civil and Environmental Engineering Chair, Departmental Committee for Graduate Students TRENDS AND INNOVATIONS IN HIGH-RISE BUILDINGS OVER THE PAST DECADE by Wenjia Gu Submitted to the Department of Civil and Environmental Engineering on May 21, 2015 in Partial Fulfillment of the Degree Requirements for Master of Engineering in Civil and Environmental Engineering ABSTRACT Over the past decade, high-rise buildings in the world are both booming in quantity and expanding in height. One of the most important reasons driven the achievement is the continuously evolvement of structural systems. In this paper, previous classifications of structural systems are summarized and different types of structural systems are introduced. Besides the structural systems, innovations in other aspects of today's design of high-rise buildings including damping systems, construction techniques, elevator systems as well as sustainability are presented and discussed.
    [Show full text]
  • The Hows, Whats and Wows of the Willis Tower a Guide for Teachers Skydeck Chicago
    THE HOWS, WHATS AND WOWS OF THE WILLIS TOWER A GUIDE FOR TEACHERS SKYDECK CHICAGO PROPERTY MANAGED BY U.S. EQUITIES ASSET MANAGEMENT LLC WELCOME TO SKYDECK CHICAGO AT WILLIS TOWER THE NATION’S TALLEST SCHOOL When you get back to your school, we hope your students will send us photos or write or create There are enough impressive facts about the Willis artwork about their experiences and share them Tower to make even the most worldly among us with us (via email or the mailing address at the end say, “Wow!” So many things at the Willis Tower can of this guide). We’ve got 110 stories already, and we be described by a superlative: biggest, fastest, would like to add your students’ experiences to our longest. But there is more to the building than all collection. these “wows”: 1,450 sky-scraping, cloud-bumping feet of glass and steel, 43,000 miles of telephone One photo will be selected as the “Photo of the cable, 25,000 miles of plumbing, 4.56 million Day” and displayed on our Skydeck monitors for all square feet of floor space and a view of four states. to see. Artwork and writing will posted on bulletin boards in the lunchroom area. Your students also Behind the “wows” are lots of “hows” and “whats” can post their Skydeck Chicago photos to the Willis for you and your students to explore. In this Tower or Skydeck Chicago pages on flickr, a free guide you will be introduced to the building—its public photo-sharing site: http://www.flickr.com/ beginnings as the Sears Tower and its design, photos/tags/willistower/ or http://www.flickr.com/ construction and place in the pantheon of photos/skydeckchicago/ skyscrapers.
    [Show full text]
  • Petronas Office Towers
    2Q6LWH5HYLHZ5HSRUW 0$/ E\*DODO$EDGD 3HWURQDV2I¿FH7RZHUV .XDOD/XPSXU0DOD\VLD $UFKLWHFW &HVDU3HOOLDQG$VVRFLDWHV &OLHQW .XDOD/DPSXU&LW\&HQWUH+ROGLQJ6GQ%KG 'HVLJQ &RPSOHWHG Petronas Towers Kuala Lumpur, Malaysia I. Introduction The Petronas Towers were designed to be the centrepiece of a larger complex called the Kuala Lumpur City Centre (KLCC), a mixed-use development with a site area of 14.15 acres, which includes the towers, two other office towers, underground parking and service facilities. The project site is well located in the heart of the commercial district of the city, the ‘Golden Triangle’. Each of the twin towers is eighty-eight storeys high and contains 218,000 square metres of floor space. Rising 452 metres, the towers were certified the world’s tallest buildings by the Council of Tall Buildings and Urban Habitat in 1996. The two towers are connected by a sky bridge at the forty-first and forty-second floors – the sky lobby levels – to facilitate inter-tower communication and traffic. A multi-storey shopping and entertainment galleria connects the office towers at their bases, integrating the entire complex. Other public functions within the complex include the Petroleum Discovery Centre, an art gallery, an 865- seat concert hall and a multimedia conference centre. II. Contextual Information A. Historical background In early 1981 the Malaysian Government decided to move the Selangor Turf Club and its horse-racing track from the heart of the city to the periphery and to redevelop the site to meet the demands of urban and economic growth. The site, occupying 100 acres of land in a burgeoning economic catchment area with access to the city‘s main ring road, offered an ideal location for the development of a new city centre that would reinforce Kuala Lumpur‘s emerging status as an international city in the twenty-first century.
    [Show full text]
  • Investigation of Shear Lag Effect in High-Rise Buildings with Diagrid System
    Investigation of Shear Lag Effect in High-rise Buildings with Diagrid System by Johan Leonard B.S., Civil Engineering (2004) Illinois Institute of Technology Submitted to the Department of Civil and Environmental Engineering in Partial Fulfillment of the Requirements for the Degree of Master of Engineering in Civil and Environmental Engineering at the Massachusetts Institute of Technology June 2007 © 2007 Johan Leonard All rights reserved The author hereby grants MIT permission to reproduce and to distribute publicly paper and electronic copies of this thesis document in whole or in part in any medium now known or hereafter created Signature of Author .......................................................................................................... Department of Civil and Environmental Engineering May 21, 2007 Certified by ...................................................................................................................... Jerome J. Connor Professor of Civil and Environmental Engineering Thesis Supervisor Accepted by ..................................................................................................................... Daniele Veneziano Chairman, Departmental Committee for Graduate Students Investigation of Shear Lag Effect in High-rise Buildings with Diagrid System by Johan Leonard B.S., Civil Engineering (2004) Illinois Institute of Technology Submitted to the Department of Civil and Environmental Engineering in Partial Fulfillment of the Requirements for the Degree of Master of Engineering in Civil and Environmental Engineering ABSTRACT In the recent years, there have been many new skyscrapers built which soar into new heights. The most efficient building system for high-rises has been the framed tube system. However, the framed tube building suffers from shear lag effects which cause a nonlinear distribution of axial stresses along the face of the building. A particular structural system called a diagrid system has caught the attention of the public. The diagrid system is not a new invention.
    [Show full text]