ISBN Verlag Ernst & Sohn - Berlin. Preliminary remarks... VI. 1 Introduction...1

Size: px

Start display at page:

Download "ISBN Verlag Ernst & Sohn - Berlin. Preliminary remarks... VI. 1 Introduction...1"

Beverly Wheeler
6 years ago
Views:

Seite 1 Inhaltsverzeichnis und Vorwort Structural Bearings ISBN 3-433-01238-5 Verlag Ernst & Sohn - Berlin Contents Preface...V Preliminary remarks... VI 1 Introduction...1 1.1 History...1 1.2 Terms and descriptions.

3 Basic guidelines for selecting the Support system...5 1.4 Bearing motion...6 1.4.1 General...6 1.4.2 Displacements caused by temperature... 10 1.4.3 Displacements caused by prestressing, creep, and shrinkage.

1 Seite 1 Inhaltsverzeichnis und Vorwort Structural Bearings ISBN Verlag Ernst & Sohn - Berlin Contents Preface...V Preliminary remarks... VI 1 Introduction History Terms and descriptions Support and bearings as part of the structure Roll-off, sliding, deformation Bearing, hinge, pendulum Bearing definitions Basic guidelines for selecting the Support system Bearing motion General Displacements caused by temperature Displacements caused by prestressing, creep, and shrinkage Displacements in the bearings caused by outer loads Support rotation Bearing symbols Rotational resistance Basic moment Restoring moment and rotation Other dependencies Influence of horizontal forces Influence of the restoring moment an the structure... 17

2 Seite 2 2 Structure and bearing system Introduction Bridges Influence of different bridge cross sections Influence of the bridge plan view Single span bridges (orthogonal) Single span skew bridge Two span bridge (orthogonal) Two span skew bridge Continuous beams (orthogonal) Continuous beams (curved) Examples of bearing systems Single span bridge (orthogonal) Two span skew bridge Continuous beams (orthogonal) Continuous beams (curved) Subsoil influence Vibration control of buildings Structures in seismic zones From specification to installation of bearings Structure and bearing loads From a hinge to a bearing Bridge analysis Introduction Transfer of vertical loads Transfer of horizontal loads in longitudinal bridge direction Transfer of horizontal loads in lateral bridge direction Loads depending an the type of bearing Bearing motion Stability (protection against sliding, overturning, and uplift) Safety considerations based an bearing properties Influence of bearings an the stability of constructions General Boundary and special conditions for bearings Buckling lengths of columns General Single columns Straight bridges with columns of differing lengths Straight bridge with only two column types Straight bridges with rocker bearings Curved bridges Elastic restraint, variable bending resistance, and longitudinal force Proof of total system safety... 64

3 Seite Bearings with high vertical flexibility Bearings for vibration control Basics of vibration and structure-borne noise control Elements for vibration isolation Coil spring elements Viscodampers Elastomeric bearings Comparison of coil springs and elastomeric bearings Bearings for protection against settlements/subsidences Elastic support of buildings Introduction Vibration control (mechanical vibrations) Structure-bome noise control Selection of elastic bearings for vibration and structure-bome noise control Base isolation of entire buildings Spring support of partial building areas (room-in-room) Seismic base isolation Track-bed isolation Bearing types Basic remarks General design and dimensioning rules Materials Types of steel for bearing parts Elements for holt connections according to EC Peculiarities of connectors made of stainless steel Welding Sectional data and degrees of freedom Rules for dimensioning Bearing plates Bolt connections Weld connections Pressure in the bearing joints Verification of static equilibrium Practical advice an the transmission of horizontal loads in the bearing joints Anchoring through stud holt dowels Corrosion protection Fixed bearings Introduction Steel point rocker bearings Pot bearings Spherical bearings Fixed deformation bearings General information Journal bearings Pot deformation bearings

4 Seite Sliding bearings Introduction Guidelines Sliding bearing system Dimensioning of the bearing plates Sliding plate and PTFE-housing Design of the PTFE-housing Point rocker sliding bearings Introduction Design and dimensioning Design basics for the PTFE-housing Load eccentricities for the analysis of the stresses in the PTFE sliding surface Load eccentricities for the analysis of the upper and lower bearing joints Pot sliding bearings Basics Design and dimensioning Design basics for the PTFE-housing Load eccentricities for pressure analysis in the PTFE sliding surface Load eccentricities for the analysis of the upper and lower bearing joint Spherical bearings Basics Design and dimensioning Design of the PTFE-housing Load eccentricities for the analysis of stresses in the PTFE sliding surfaces Load eccentricities for the analysis of the upper and lower bearing joints Stresses in the PTFE guide surfaces Deformation sliding bearings Basics Design and dimensioning Design basics for the PTFE-housing Load eccentricities for the analysis of the pressure in the PTFE sliding surface Load eccentricities for the analysis of the upper and lower bearing joints Elastomer sliding bearings Basics Design and dimensioning Design of the PTFE-housing Load eccenfricities for the analysis of the pressure in the PTFE sliding surface Load eccentricities for the analysis of the upper and lower bearing joints Deformation bearings History Applicable material Physical properties Rubber elasticity Shear modulus Elasticity modulus Stability Creep and relaxation Stick friction Future design rules

5 Seite Special reinforced elastomeric bearings Pre-adjusted elastomeric bearings with presetting Elastomeric bearings with low rotation resistance Standards Preliminary remarks Imprint from EN : General design rules Remarks an EN : Sliding elements Remarks an the draft of EN : Elastomeric bearings Remarks an the draft of EN : Pot bearings Remarks an EN : Spherical and cylindrical PTFE-bearings Remarks an the draft of EN : Guide bearings and restraint bearings Remarks an the draft of EN : Inspection and maintenance Imprint of EN : Transport, storage and installation Approvals German Approval of sliding bearings (example) German Approval of spherical bearings (two examples) Pot bearing: special conditions (in part) and appendices German Approval of a bearing for vibration control Science and research General Research reports Long-term friction and wear tests with sliding bearings, different slidingsurfaces Long-term friction and wear tests with PTFE sliding bearings,iii c quality Investigation of friction behavior of PTFE through variation of the influence parameters: Sliding speed, pressure, bearing size, total way (wear), bearing system, load eccentricity Dependence of thickness an the temperature and size of elastomeric bearings Rupture tests with bearing plates Permissible horizontal forces for nonanchored bearings Permissible horizontal loads at nonanchored bearings: Supplementary tests an zinc-coated steel plates On the slip-resistance of nonanchored elastomeric bearings Determination of the characteristic values of the friction coefficients Steel bridge bearing movements

6 Seite Load-bearing capacity and reliability of reinforced concrete compression members Map of the lowest median daily temperature in Germany Approval tests Sliding bearing tests General Results of investigations an PTFE sliding bearings Model bearings Reviewed bridge bearings Results of investigations with composite sliding bearings Materials Testing technique Tribological behavior Summary Pot bearing tests General Material testing Control of finished test bearing Wear test Determination of the restoring moment Ultimate load test Permanent load test Summary and future work Glossary Literature Literature, with brief comments General literature Historicalliterature Testreports Practical applications Analysis Cited literature Subject index

7 Seite 7 Preface Organization of this book Like its German edition, this book has nine main chapters. These chapters are broken down in the list of contents into a maximum of five section levels. In the text, some further subdivision is used to improve ease of reading and referencing. The use of a glossary, which provides a brief definition of subject index terms, is not very common in technical books; we have included one in this book in the hope that it will aid readers in their understanding of this special subject. Contents This book should provide sufficient answers to typical questions related to the design and construction of bridges and industrial structures. Topics covered include: how to support a structure (chapter 2), which loads are transferred from the structure into the bearing (chapter 3) what types of bearings are available (chapter 4), and which technical guidelines must be taken into account (chapter 5). Chapter 6 provides information an the Approvals of the German Institute for Civil Structures (Deutsches Institut für Bautechnik, DIBt). Reports dealing with research and scientific problems related to the subject of bearings are listed in chapter 7. This book is meant to serve as a tool for the design engineer, architect, or engineer writing specifications, for the designing, calculating, and testing engineer, and for the civil contractor. The design of a structure will usually a priori define - whether intended or not - the support system. Neglect of this connection can later result in damage if, for example, the necessary support system cannot be realized. Costs incurred by damage to bearings can be very high if complete replacement of the constructions is necessary. Examples from Germany include: unsuitable roller bearings unsuitable top sealing installation mistakes, and material mistakes (essential elastomeric bearings). The most frequent bearing damage is corrosion damage. Serious economic damage can also be caused by corrosion in other fields. Chapter 4 contains proposals for construction with low levels of corrosion. The word "bearing" has different technical meanings. This book refers to bearings as technical parts that are manufactured in special plants and used in structures as an interface between the substructure and superstructure. It transfers loads in a defined way and allows for motion or displacements. The different types of bearings are characterized by their function as well as their main material (see section 1.2.4). The glossary provides further definitions.

8 Seite 8 Centering elements built together with the structure, such as concrete hinges, are not covered in this book. This book concentrates an bridges, the classic application of the bearing technique. It mainly deals with nondynamic applications but also gives some additional information an dynamic influences (see sections 2.2.5, 2.2.6, and 3.4). February 2002 Helmut Eggert Wolfgang Kauschke Preliminary remarks We wish to thank everyone who has helped us produce this book, particularly our wives for their patience and Dr. Günter Hüffmann for his excellent translation. Contributors to this book: Hans-Peter Rieckmann (section 3.3) Günter Hüffmann/Karl-Heinz Reinsch (section 3.4) Armin Gerber/Jochen Wiedemeyer (section 7.3.1) Karl-Heinz Hehn (section 7.3.2) Section 4.5 was revised for this edition by Florian Deischl Chapters 1 to 4, 8, and 9 were translated into English by Günter Hüffmann

Design of Steel-Concrete Composite Bridges

Design of Steel-Concrete Composite Bridges to Eurocodes Ioannis Vayas and Aristidis Iliopoulos CRC Press Taylor & Francis Croup Boca Raton London New York CRC Press is an imprint of the Taylor & Francis