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The Applicability of Advanced Composite Structural Members by Joseph Matthew Tripi

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The Applicability of Advanced Composite Structural Members by Joseph Matthew Tripi THE APPLICABILITY OF ADVANCED COMPOSITE STRUCTURAL MEMBERS BY JOSEPH MATTHEW TRIPI BACHELOR OF ARCHITECTURAL ENGINEERING MAY 1998 THE PENNSYLVANIA STATE UNIVERSITY 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 MASSACHUSET MASSACHUSETTS INSTITUTE OF TECHNOLOGY OF TECH! JUNE 1999 © 1999 J.M. Tripi. All Rights Reserved. L The Author Hereby Grants to MIT Permission to Reproduce and to Distribute Publi # c Electronic Copies of This Thesis Document in Whole or in Part. SIGNATURE OF AUTHOR TRIPI / JOSEPH MATTHEW / May 12, 1999 CERTIFIED BY fte . y JEROME J. CONNOR Professor, Department of Civil and Environmental Engineering Thesis Supervisor APPROVED BY I -~ANDREWJ. WHITTLE Chairman, Departmental Committee on Graduate Studies THE APPLICABILITY OF ADVANCED COMPOSITE STRUCTURAL MEMBERS BY JOSEPH MATTHEW TRIPI SUBMITTED TO THE DEPARTMENT OF CIVIL AND ENVIRONMENTAL ENGINEERING ON MAY 12, 1999 IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF ENGINEERING IN CIVIL AND ENVIRONMENTAL ENGINEERING ABSTRACT Advanced composite materials (ACM) are seeing increased usage in civil and architectural engineering applications. An important distinction should be noted between applications that use advanced composite materials and the term "composite construction", which is frequently used to describe floor system designs that employ steel beam members acting in conjunction with a concrete deck to resist flexural loads. Alternatively, designs with advanced composite materials include structural members that are made up of a large number of fibrous elements, referred to as reinforcement, embedded in a continuous phase of a second material known as the matrix. The scope of this document includes only advanced composite material designs, and is further refined to include only those applications where such designs involve new-construction as opposed to repair or rehabilitation. Evidence is provided that justifies the positive growth trend in the use of advanced composites, and demonstrates that advanced composite materials are both viable and cost competitive in many structural applications. A study of six requirements that are fundamental to the use of composites in new-construction applications is presented: 1) well defined material systems and processing methods are established 2) adequate secondary manufacturing processes exist 3) a sufficient manufacturing base is present 4) design and life predication methods are developed 5) non-destructive evaluation methods are effective 6) life cycle costs are competitive Case studies involving the use of these materials in structural applications are presented and compared to similar designs using conventional materials. THESIS SUPERVISOR: JEROME J. CONNOR TITLE: PROFESSOR OF CIVIL AND ENVIRONMENTAL ENGINEERING ACKNOWLEDGEMENTS Accomplishment of any such objective requires the support of others. I wish to acknowledge Professor Jerome J. Connor and Mr. Charles H. Helliwell for their assistance in developing and revising this document. Additional thanks are extended to the 1999 High Performance Structures group, my colleagues, for their conversation and moral support. 3 Table of Contents IN T R O D U C T IO N ......................................................................----.............. --. ................ 8 PART I- APPLICABILITY OF COMPOSITES IN NEW-CONSTRUCTION A PPLIC A T ION S...................................................................................-........ ------............. 10 CHAPTER 1- O VERVIEW ................................................................................ 11 1.1 Potential Benefits Advanced Composites ............................................................................ 11 1.2 Challenges to the use of Advanced Composites ................................................................. 12 CHAPTER 2- MATERIAL SYSTEMS AND PROCESSING METHODS........................................ 13 2.1 M aterial Systems.................................................................................................................... 13 2.2 Processing M ethods.........................................................................................-------------....... 14 2.3 Sum mary .................................................................................- ..... -. ------------------................... 17 CHAPTER 3- SECONDARY PROCESSES............................................................................... 18 3.1 M achining Processes............................................................................................................. 18 3.2 Joining Techniques ............................................................................................---.........------ 19 3.3 Summ ary................................................................................................................................ 22 CHAPTER 4- M ANUFACTURING BASE ............................................................................ 23 4.1 M aterial Sources.................................................................................................................... 23 4.2 Producers and Availability .................................................................................................... 23 4.3 Summary .........................................................................- .------------...................................... 24 CHAPTER 5- DESIGN METHODS AND LIFE PREDICTION..................................................... 25 5.1 Brief H istory .......................................................................................................................... 25 5.2 Design Strategy...................................................................................................................... 25 5.3 H um an Safety & Environmental Issues ............................................................................. 27 5.4 Reliability and Lifetime Prediction...................................................................................... 29 5.5 Sum mary ................................................................................... ..- -..-.---------..................... 30 CHAPTER 6- NON-DESTRUCTIVE EVALUATION METHODS............................................... 31 6.1 Visual Inspection and Tap Test........................................................................................... 31 6.2 Ultrasonics............................................................................................................................. 32 6.3 X-Radiology ........................................................................................................................... 33 6.4 Acoustic Em ission.................................................................................................................. 34 6.5 Infrared Thermography ......................................................................................................... 34 6.6 Vibrothermography............................................................................................................... 36 6.7 Laser Interferometry.............................................................................................................. 36 6.8 M icrowave Testing ................................................................................................................ 37 6.9 Eddy Current Testing............................................................................................................. 38 6. 10 Summ ary .............................................................................................................................. 38 CHAPTER 7- LIFE CYCLE COSTS ................................................................................... 40 7.1 Construction Cost-Time Relationship.................................................................................. 40 7.2 Life Cycle Cost-Benefit Model for Composite M aterials................................................... 42 7.3 Summary .............................................................................................-------................... 44 4 PART II- COMPOSITE MATERIALS APPLICATIONS IN NEW CONSTRUCTION ....................................................--..........--.... 45 CHAPTER 8- CURRENT NEW-CONSTRUCTION APPLICATIONS ........................................... 46 8.1 Advanced Composite Case Studies..................................................................................... 47 8.2 Conceptual Design of a Showcase Building ..................................................................... 54 8.3 S u m m a ry ................................................................................................................................ 5 8 CHAPTER 9- FUTURE APPLICATIONS..................................................................... ............. 59 9.1 Advances in Material System s ......................................................................................... 59 9.2 Advances in ProcessingM ethods ....................................................................................... 59 9.3 Advanced Applications ....................................................................................... ....... 60 9 .4 S u m m a ry ................................................................................................................................ 6 0 CONCLUSION..................................--...--...---
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