BRIDGE ENGINEERING BRIDGE ENGINEERING Classifications, Design Loading, and Analysis Methods WEIWEI LIN TERUHIKO YODA Butterworth-Heinemann is an imprint of Elsevier The Boulevard, Langford Lane, Kidlington, Oxford OX5 1GB, United Kingdom 50 Hampshire Street, 5th Floor, Cambridge, MA 02139, United States © 2017 Elsevier Inc All rights reserved No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage and retrieval system, without permission in writing from the publisher Details on how to seek permission, further information about the Publisher’s permissions policies and our arrangements with organizations such as the Copyright Clearance Center and the Copyright Licensing Agency, can be found at our website: www.elsevier.com/permissions This book and the individual contributions contained in it are protected under copyright by the Publisher (other than as may be noted herein) Notices Knowledge and best practice in this field are constantly changing As new research and experience broaden our understanding, changes in research methods, professional practices, or medical treatment may become necessary Practitioners and researchers must always rely on their own experience and knowledge in evaluating and using any information, methods, compounds, or experiments described herein In using such information or methods they should be mindful of their own safety and the safety of others, including parties for whom they have a professional responsibility To the fullest extent of the law, neither the Publisher nor the authors, contributors, or editors, assume any liability for any injury and/or damage to persons or property as a matter of products liability, negligence or otherwise, or from any use or operation of any methods, products, instructions, or ideas contained in the material herein Library of Congress Cataloging-in-Publication Data A catalog record for this book is available from the Library of Congress British Library Cataloguing-in-Publication Data A catalogue record for this book is available from the British Library ISBN: 978-0-12-804432-2 For information on all Butterworth-Heinemann publications visit our website at https://www.elsevier.com/books-and-journals Publisher: Matthew Deans Acquisition Editor: Ken McCombs Editorial Project Manager: Peter Jardim Production Project Manager: Anusha Sambamoorthy Cover Designer: Mark Rogers Typeset by SPi Global, India ABOUT THE AUTHORS Weiwei Lin is a member of the Department of Civil and Environmental Engineering and International Center for Science and Engineering Programs (ICSEP), Waseda University, holding associate professorship in the Bridge Engineering Laboratory He has authored or coauthored over 100 academic papers, proceedings, and technical articles dealing with the problems of structural mechanics and bridge engineering, especially for the steel structures and steel-concrete composite structures He is a member of several engineering committees, like ASCE, JSCE, IABSE, IABMAS, IALCCE, etc He is also the recipient of IABMAS YOUNG PRIZE of 2014 Teruhiko Yoda is on the faculty of Waseda University, where he holds the chair professorship in the Department of Civil and Environmental Engineering He has authored or coauthored technical books and over 400 articles dealing with the problems of structural mechanics and bridge engineering He is a member of the ASCE, JSCE, and IABSE and former chairman of International Committee of JSCE, and the former president of Kanto Branch of JSCE Besides, he is chairman of the Drafting Committee for Standard Specifications for Steel and Composite Structures (First Edition 2007) He is the recipient of many Japanese awards, including the prestigious Tanaka Award ix CHAPTER ONE Introduction of Bridge Engineering 1.1 INTRODUCTION A bridge is a construction made for carrying the road traffic or other moving loads in order to pass through an obstacle or other constructions The required passage may be for pedestrians, a road, a railway, a canal, a pipeline, etc Obstacle can be rivers, valleys, sea channels, and other constructions, such as bridges themselves, buildings, railways, or roads The covered bridge at Cambridge in Fig 1.1 and a flyover bridge at Osaka in Fig 1.2 are also typical bridges according to above definition Bridges are important structures in modern highway and railway transportation systems, and generally serving as “lifelines” in the social infrastructure systems Bridge engineering is a field of engineering (particularly a significant branch of structural engineering) dealing with the surveying, plan, design, analysis, construction, management, and maintenance of bridges that support or resist loads This variety of disciplines requires knowledge of the science and engineering of natural and man-made materials, composites, metallurgy, structural mechanics, statics, dynamics, statistics, probability theory, hydraulics, and soil science, among other topics (Khan, 2010) Similar to other structural engineers (Abrar and Masood, 2014), bridge engineers must ensure that their designs satisfy given design standard, being responsible to structural safety (i.e., bridge must not deform severely or even collapse under design static or dynamic loads) and serviceability (i.e., bridge sway that may cause discomfort to the bridge users should be avoided) Bridge engineering theory is based upon modern mechanics (rational knowledge) and empirical knowledge of different construction materials and geometric structures Bridge engineers need to make innovative and high efficient use of financial resources, construction materials, calculation, and construction technologies to achieve these objectives Bridge Engineering http://dx.doi.org/10.1016/B978-0-12-804432-2.00001-3 © 2017 Elsevier Inc All rights reserved Bridge Engineering Fig 1.1 The Bridge of Sighs, Cambridge, the United Kingdom (Photo by Lin.) Fig 1.2 A flyover in Osaka, Japan (Photo by Lin.) Introduction of Bridge Engineering 1.2 BRIDGE COMPONENTS 1.2.1 Superstructure, Bearings, and Substructure Structural components of bridges are based on parametric definitions involving deck types and various bridge properties Bridge structures are composed of superstructure, bearing, superstructure, and accessories (A) Superstructure In general, the superstructure represents the portion of a bridge above the bearings, as shown in Fig 1.3 Superstructure is the part of a bridge supported by the bearings, including deck, girder, truss, etc The deck directly carries traffic, while other portions of the superstructure bear the loads passing over it and transmit them to the substructures In case, the deck was divided as a separate bridge component, and the structural members between the deck and the bearings are called as bridge superstructure The superstructure may only include a few components, such as reinforced concrete slab in a slab bridge, or it may include several components, such as the floor beams, stringers, trusses, and bracings in a Bridge length Span length Span length Clearance above bridge floor Superstructure Substructure Abutment Bearing Pier Clearance of bridge span Abutment Foundation (A) Total width Deck width Lane (driveway) Sidewalk Parapet Shoulder Sidewalk Shoulder Separator Pavement Deck Main girder (B) Fig 1.3 General terminology of bridges (A) Longitudinal direction (B) Cross section Bridge Engineering truss bridge In suspension and cable-stayed bridges, components such as suspension cables, hangers, stays, towers, bridge deck, and the supporting structure comprise the superstructure (Taly, 1997) (B) Bearings A bridge bearing is a component of a bridge transmitting the loads received from the deck on to the substructure and to allow controlled movement due to temperature variation or seismic activity and thereby reduce the stresses involved A bearing is the boundary between the superstructure and the substructure (C) Substructure Substructure is the portion of the bridge below the bearing, used for supporting the bridge superstructure and transmits all those loads to ground In this sense, bridge substructures include abutments, piers, wing walls, or retaining walls, and foundation structures like columns and piles, drilled shafts that made of wood, masonry, stone, concrete, and steel Both abutments and piers are vertical structures used for supporting the loads from the bridges bearings or directly from the superstructures and for transmitting the load to the foundation However, the abutments refer to the supports located at beginning or end of bridge, while the piers are the intermediate supports Therefore, a bridge with a single span has only abutments at both ends, while multispan bridges also need intermediate piers to support the bridge superstructures, as can be seen in Fig 1.3 (D) Accessory structures Bridge accessories are structure members subordinate to the main bridge structure, such as parapets, service ducts, and track slabs Deadweight of accessory structures shall be considered in the design, but their load carrying capacities are generally ignored 1.2.2 Bridge Length, Span Length, and Bridge Width The distance between centers of two bearings at supports is defined as the span length or clear span The distance between the end of wing walls at either abutments or the deck lane length for bridges without using abutments is defined as total bridge length Obviously, the bridge length is different from the span length For example, the world’s largest bridge (means the span length) is the Akashi Kaikyo¯ Bridge in Japan (with the central span of 1991 m), while the longest bridge (means the total length) is the Introduction of Bridge Engineering Danyang-Kunshan Grand Bridge in China, which is a 164.8-km long viaduct on the Beijing-Shanghai High-Speed Railway Deck width is the sum of the carriageway width, sidewalk width, shoulder width, and the individual elements required to make up the desired bridge cross section The total bridge width not only includes the deck width but also the width of the bridge accessories such as parapets The lane width is determined according to the bridge design codes, generally with the minimum width of 2.75 m and the maximum width of 3.5 m 1.2.3 Bridge Clearance There are two types of bridge clearance, including clearance of bridge span and clearance above bridge floor Clearance of bridge span is generally measured from the water surface (or ground, if there is no water) to the undersurface of the bridge The measurement from the mean highest high water (MHHW) is the most conservative clearance, thus in most cases the real clearance is larger than this value due to the lower water surface than the highest point at MHHW Enough clearance should be considered in the bridge design to ensure the traffic safety under the bridge Clearance above bridge floor is the space limit for carriageway and sidewalk, which is generally specified in the bridge design specification to ensure the traffic safety (enough height or space) above the bridge 1.3 BRIDGE CLASSIFICATION Depending on the objective of classification, the bridges can be classified in several ways The necessity of classifying bridges in various ways has grown as bridges have evolved from simple beam bridges to modern cablestayed bridges or suspension bridges Bridges are always classified in terms of the bridge’s superstructure, and superstructure can be classified according to the following characteristics: Materials of construction Span length Position (for movable bridges) Span types Deck location Usage Geometric shape Structural form Bridge Engineering 1.3.1 Bridge Classification by Materials of Construction Bridges can be identified by the materials from which their superstructures are built, namely, steel, concrete, timber, stone, aluminum, and advanced composite materials This is not suggested that only one kind of material is used exclusively to build these bridges Frequently, a combination of materials is used in bridge building For example, a bridge may have a reinforced concrete deck and steel main girders, which is typically used in highway bridge superstructures New materials such as advanced composite materials have also been widely used in bridge construction 1.3.2 Bridge Classification by Span Length In practice, it is general to classify bridges as short span, medium span, and long span, according to their span lengths The concept of “super-long span bridges,” defining a bridge with a span much longer than any existing bridges, was also proposed in recent years (Tang, 2016) However, up to now there are no standard criteria to define the range of spans for these different classifications A criterion proposed by Taly (1997) is to classify bridges by span length as follows: Culverts Short-span bridges Medium-span bridges Long-span bridges L 20 ft ($6 m) 20 ft < L 125 ft (approximately from to 38 m) 125 ft < L 400 ft (approximately from 38 to 125 m) L > 400 ft (125 m $ ) As already discussed above, this is an often used but not a standard criterion Taking the long span as an example, it was also proposed that a span length less than or equal to 180 (Lutomirska and Nowak, 2013) or 200 m (Catbas et al., 1999) The current bridge design specification for highway bridges in Japan is applicable for a bridge with a span length