New Composite Materials

New Composite Materials

Domenico Brigante New Composite Materials Selection, Design, and Application

Domenico Brigante Olympus FRP - BRIGANTE ENGINEERING Group Napoli, Italy ISBN 978-3-319-01636-8 ISBN 978-3-319-01637-5 (ebook) DOI 10.1007/978-3-319-01637-5 Springer Cham Heidelberg New York Dordrecht London Library of Congress Control Number: 2013952926 Springer International Publishing Switzerland 2014 This work is subject to copyright. All rights are reserved by the Publisher, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed. Exempted from this legal reservation are brief excerpts in connection with reviews or scholarly analysis or material supplied specifically for the purpose of being entered and executed on a computer system, for exclusive use by the purchaser of the work. Duplication of this publication or parts thereof is permitted only under the provisions of the Copyright Law of the Publisher s location, in its current version, and permission for use must always be obtained from Springer. Permissions for use may be obtained through RightsLink at the Copyright Clearance Center. Violations are liable to prosecution under the respective Copyright Law. The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. While the advice and information in this book are believed to be true and accurate at the date of publication, neither the authors nor the editors nor the publisher can accept any legal responsibility for any errors or omissions that may be made. The publisher makes no warranty, express or implied, with respect to the material contained herein. Printed on acid-free paper Springer is part of Springer Science+Business Media (www.springer.com)

Thanks to Giusi and Francesco and Antonio, Prof. I. Crivelli Visconti and Claudio Cigliano. Thanks to my grandparents. Thanks to Gabriella Piscopo for the translation.

Foreword It was a real pleasure for me to find out about the volume New Composite Materials: Selection, Design, and Application authored by Domenico Brigante, a clear demonstration that the education given to our students during their university years is not always neglected nor forgotten. In the case of Dr. Brigante, the publishing of this book states the relevance and importance of spreading technical and scientific knowledge in the pursuit of a kind of continuity over time in the development of positive achievements, as has happened for composite materials, thus leading to an improvement in our everyday social and technical lives. This book deals precisely with the use of composites in civil construction and architecture, a field involving each and every one of us that is now, after many years of hesitation and doubts, finally interested in the huge potential represented by composites. Extremely relevant and diverse from other minor technical publications dealing with building issues, this volume focuses extensively on the description of the characteristics of the techniques employed for buildings or for the structural restoration of specific monuments or simple common constructions. This is actually a prevailing aspect in the use of composite materials, diverse from the use of traditional materials, since the final properties of the products or applications strongly depend on the same way that different materials are applied that should be accurately designed and distributed following the most effective procedures which designers can only choose if they have a deep and accurate knowledge of the techniques required. This is true for the use of both composites on wooden or steel and concrete structures whose different existing possibilities are carefully detailed in this volume. The examples and descriptions of inspection and monitoring procedures crown the volume, making it an effective tool for designers and for final users as well. Napoli, Italy Ignazio Crivelli Visconti vii

Contents 1 Composite Materials... 1 1.1 Composite Materials... 1 1.2 Main Properties... 2 1.3 Fibers... 3 1.3.1 Glass Fibers... 4 1.3.2 Carbon Fibers... 6 1.3.3 Basalt Fibers... 7 1.3.4 Aramid Fibers... 8 1.3.5 Steel Fibers... 10 1.3.6 Hybrid Fabrics... 11 1.3.7 Natural Fibers... 11 1.3.8 Cost Aspects of Fibers... 12 1.4 Matrices... 12 1.5 Plastic Matrices... 13 1.5.1 Polyester Resins... 15 1.5.2 Epoxy Resins... 15 1.5.3 Phenolic Resins... 15 1.5.4 Silicone Resins... 15 1.6 Grout-Based Matrices... 16 1.7 Other Types of Matrices... 16 1.7.1 Metal Matrices... 16 1.7.2 Ceramic Matrices... 16 1.8 Thermoplastic Matrices... 17 2 Manufacturing Processes... 19 2.1 Manufacturing Technologies... 19 2.1.1 Composite Materials Production Processes... 20 2.2 Hand Impregnation Without Pressure or Vacuum... 20 2.3 Filament Winding... 20 2.3.1 Winding... 21 2.3.2 Impregnation... 22 ix

x Contents 2.3.3 The Mandrel... 22 2.3.4 Machines... 22 2.4 Pultrusion... 23 2.4.1 Reinforcement Feeding... 24 2.4.2 Impregnation... 25 2.4.3 Preforming... 26 2.4.4 Forming and Polymerization... 27 2.5 Resin Transfer Molding... 30 2.6 Resin Infusion Under Flexible Tooling... 30 2.7 Autoclave Forming... 32 2.8 FRP Grids... 34 3 Choice of the Composite System... 35 3.1 Advantages of Composite Materials... 35 3.2 Design of the Materials... 37 3.3 FRP: Fiber-Reinforced Polymer... 37 3.4 SRP: Steel-Reinforced Polymer... 38 3.5 FRG: Fiber-Reinforced Grout... 39 3.6 SRG: Steel-Reinforced Grout... 39 3.7 Choice of the Composite System... 40 3.8 Flatness of Strengthening Structures Surfaces... 40 3.9 Impact of Temperature... 41 3.10 Behavior in Humidity... 41 3.11 Employment of Skilled Labor... 41 3.12 Employment of Individual Safety Devices... 42 3.13 Full Deterioration of Work Tools... 42 3.14 Fire Resistance... 42 3.15 Resistance to UV Rays... 43 3.16 Radiotransparency... 44 4 Strengthening of Existing Structures: Technical Standards... 45 4.1 International Technical Standards... 45 4.2 Main Standards... 47 4.2.1 CNR guidelines... 47 4.2.2 Canadian Guidelines... 47 4.2.3 American Guidelines... 48 4.2.4 Fib Guidelines... 50 4.2.5 Japanese Guidelines... 51 4.3 Comparison of Standards About Flexural Strengthening... 51 4.3.1 JSCE Code... 51 5 Strengthening of Reinforced and Prestressed Reinforced Concrete Structures... 55 5.1 Italian Technical Paper CNR-DT 200/2004... 55 5.2 Draft of Guidelines: Department of Italian Civil Protection ReLUIS... 56

Contents xi 5.3 Guidelines of the General Assembly of Higher Council for Public Works (CSLLPP Guidelines)... 58 5.4 Symbols... 58 5.4.1 General Notations... 59 5.4.2 Uppercase Roman Letters... 59 5.4.3 Lowercase Roman Letters... 60 5.4.4 Lowercase Greek Letters... 61 5.5 Introduction... 62 5.5.1 Partial Factors... 62 5.5.2 Partial Factors γ m for Materials and Products... 62 5.5.3 Partial Factors γ Rd for Resistance Models... 63 5.5.4 Environmental Action and Conversion Factors η a... 63 5.5.5 Loading Mode and Conversion Factor for Long-Term Effect η l... 63 5.6 Failure Mechanisms Due to Debonding... 64 5.6.1 Verification of Safety Following Debonding... 65 5.7 Flexural Strengthening... 67 5.7.1 Analysis at the Ultimate State Limit... 69 5.7.2 Behavioral Analysis at the Serviceability Limit State... 71 5.8 Shear Strengthening... 72 5.8.1 Design of Shear Strengthening... 74 5.9 Reinforcement of Floors in Brick and Cement... 76 5.10 Strengthening of r.c. Columns... 77 5.10.1 Design Axial Capacity Under Concentric and Slightly Eccentric Force of the Confined Member... 78 5.10.2 Circular Sections... 80 5.10.3 Square and Rectangular Sections... 80 5.10.4 Ductility of FRP-Confined Members Under Combined Bending and Axial Loading... 81 5.11 Strengthening of Beam Column Joints... 82 5.11.1 Criteria for the Localized Strengthening of Unconfined Joints... 83 5.12 Choice of the Adequate Composite Material... 88 5.13 Seismic Applications... 90 6 Reinforcement of Masonry Structures... 95 6.1 Introduction... 95 6.2 Goals and Criteria of a Reinforcement Project... 96 6.2.1 Safety Assessments... 98 6.3 Failure Mechanisms Due to Debonding... 100 6.3.1 Resistance to Debonding in the Ultimate Limit State... 100 6.4 Reinforcement of Masonry Panels... 102 6.4.1 Checks for Out-of-Plane Loads... 102 6.4.2 Check for Simple Overturning... 103

xii Contents 6.4.3 Check for Flexural Failure of Vertical Masonry Stretching... 103 6.4.4 Check for In-plane Actions... 106 6.4.5 Combined Compressive and Bending Stress... 106 6.4.6 Shear... 106 6.5 Reinforcement of Masonry Arches and Vaults... 107 6.5.1 Simple Curvature Vaults (Barrel Vaults) and Arches... 108 6.5.2 Double Curvature Vaults... 109 6.6 Reinforcement of Masonry Columns... 109 6.6.1 Axially Loaded Confined Members... 109 6.6.2 Confinement of Circular Columns... 111 6.6.3 Confinement of Squared or Rectangular Columns... 111 6.7 Pretensioning Systems... 112 6.7.1 Tensioning System for SRG SRP... 112 6.8 Anchor Systems... 116 6.9 Preparation of the Substrate... 117 7 Strengthening of Steel Structures... 119 7.1 Introduction... 119 7.2 Applications... 120 7.3 Technical Standards... 121 7.4 Repair of Steel Pipes... 122 7.5 Reinforcement of Steel Structures for Telecommunications... 124 8 Characterization and Monitoring... 127 8.1 Introduction... 127 8.2 Materials... 128 8.2.1 Pultruded Laminates... 128 8.2.2 Laminates Produced Onsite... 129 8.2.3 Production Tests... 129 8.3 Experimental Tests... 130 8.4 Work Inspection... 130 8.4.1 Destructive Tests... 131 8.4.2 Pull-off Tests... 132 8.4.3 Shear Tearing Test... 133 8.4.4 Non-destructive Test... 133 8.4.5 Stimulated Acoustic Tests... 133 8.4.6 High-Frequency Ultrasound Tests... 133 8.4.7 Thermography Tests... 133 8.4.8 Acoustic Emission Tests... 134 8.4.9 Failure Tests on Reinforced Members, Beams, and Columns... 135 8.5 Test Operators... 135

Contents xiii 9 Application Techniques... 137 9.1 Introduction... 137 9.2 Reinforcement of Floors in Brick and Cement... 137 9.2.1 General Principles... 138 9.2.2 Construction Details... 139 9.2.3 Application Procedure... 139 9.3 Reinforcement of Steel Beam Floors... 140 9.3.1 General Principles... 140 9.3.2 Construction Details... 141 9.3.3 Application Procedure... 141 9.4 Reinforcement of r.c. Columns... 142 9.4.1 General Principles... 142 9.4.2 Construction Details... 143 9.4.3 Application Procedure... 143 9.5 Shear and Bending Reinforcement of Concrete Beams... 144 9.5.1 General Principles... 145 9.5.2 Construction Details... 146 9.5.3 Application Procedure... 147 9.6 Reinforcement of Masonry Structures... 148 9.6.1 General Principles... 149 9.6.2 Construction Details... 149 9.7 Reinforcement of Masonry Arches and Vaults... 152 9.7.1 General Principles... 152 9.7.2 Construction Details... 153 9.7.3 Application Procedure... 153 9.8 Reinforcement of Wooden Bearing Structures... 154 9.8.1 Construction Details... 155 9.8.2 General Principles... 155 9.8.3 Application Procedure... 156 10 Examples of Applications... 157 10.1 Hotel Boscolo Exedra, Nice, France... 157 10.2 Telecoms Building, Rome, Italy... 157 10.3 Industrial Factory, Milan, Italy... 157 10.4 Albergo Reale dei Poveri (Bourbon Hospice for the Poor), Naples, Italy... 161 10.5 Monastery of Santa Chiara, Naples, Italy... 162 10.6 Monument for Neapolitan Martyrs, Naples, Italy... 164 10.7 Hotel Boscolo Exedra, Rome, Italy... 165 10.8 Laminated Wooden Structure, Crotone, Italy... 167 10.9 Church of San Gaetano, Bitonto, Italy... 168 10.10 Radio Station Base in Forna, Ponza, Italy... 170 Bibliography... 173 Index... 177

Introduction Over the last several years, the scientific interest towards innovative fiber-reinforced plastic (FRP) applications for structural reinforcement on one side and the peculiarity of the extremely diversified Italian architectural heritage on the other directed the attention of many researchers to the fields of structural mechanics, construction, structural reinforcement, and seismic engineering. Several scientific programs have resulted from this, funded by the most important research centers in the world. Worth mentioning are, for instance, the programming regulations drafted and issued on specific journals by the fib Task Group 9.3, the European founding committee in 1998, or the official journals of the American Concrete Institute (ACI), whose aim is to provide new guidelines for the design and construction of FRP concrete structures. A further contribution on the topic comes from the European Committee for Standardization that published the new regulations of design and strengthening with FRP in the Eurocode 8 Design of structures for earthquake resistance Part 3 Assessment and retrofitting of buildings, Draft N 7, January 2003. In Italy, the decree nr. 3274 May 2005, concerning the technical regulations for the design, evaluation, and seismic adjustment of buildings, introduces the use of FRP for the seismic strengthening of reinforced concrete (r.c.) members and specifically refers to the instructions of CNR-DT 200/2004 for the safety assessments. This volume deals with several topics strictly linked to the most up-to-date applications of composite materials in civil engineering, and industrial and historical or monumental buildings. This timely volume presents a range of critical topics on the use of composite materials in civil engineering; industrial, commercial, and residential structures; and historic buildings. Structural strengthening techniques based on composite materials represent a practice employed internationally and have become an important component in the restoration of buildings impacted by natural hazards and other destructive forces. New Composite Materials: Selection, Design, and Application stands as a highly relevant and diverse effort, distinct from other technical publications dealing with xv

xvi Introduction buildings issues. The book focuses extensively on the characterization of techniques employed for structural restoration and examines in detail an assortment of materials such as concrete, wood, masonry, and steel. This book Provides engineers and architects with a lucid explanation of how to easily design an innovative system of structural reinforcement with composite materials Presents details for readers to readily assess the feasibility of reinforcement applications Includes a section for construction managers written to facilitate the installation of composite structural reinforcement materials with maximum efficiency and cost benefit Features many examples of applications and construction details to help engineers and architects realize their projects Offers a comparative analysis among various international technical standards The structural strengthening techniques making use of composite materials, also known as FRP, currently represent a sound reality in national and international scenarios, and have become a constituent part of the restoration works of buildings impacted by earthquakes that have hit many countries. Extremely relevant and diverse from other minor technical publications dealing with buildings issues, this volume extensively focuses on the description of the characteristics of the techniques employed for buildings or for the structural restoration of specific monuments or simple common constructions. Specific aspects of the implementation of r.c. structures, wood, masonry, and steel are extensively detailed both in terms of the technical design and of the execution stages, as well as the subsequent mechanical performances of the systems obtained. This book provides a useful tool that can be applied directly to different kinds of technical documents. The examples and descriptions of inspection and monitoring procedures crown the volume, making it an effective support for designers and for final users as well. The work results in a fundamental practical handbook for any engineer, designer, architect, or any other technician who is willing to handle this innovative technique of structural strengthening. Napoli, Italy Domenico Brigante