Innovative Bridge Design Handbook

Construction, Rehabilitation and Maintenance

Alessio Pipinato

• Publisher: Butterworth-Heinemann
• Year: 2015
• ISBN:
  9780128004876
• Topic: Technology & Engineering
• Subtopic: Civil Engineering
• Index: Technology & Engineering

As known, each bridge presents a unique set of design, construction, and maintenance challenges. The designer must determine the appropriate methods and level of refinement necessary to design and analyze each bridge on a case-by-case basis. The Innovative Bridge Design Handbook: Construction, Rehabilitation, and Maintenance encompasses the state of the art in bridge design, construction, maintenance, and safety assessment. Written by an international group of experts, this book provides innovative design approaches used in various parts of the world and explores concepts in design, construction, and maintenance that will reduce project costs and increase structural safety and durability. Furthermore, research and innovative solutions are described throughout chapters.

The Innovative Bridge Design Handbook: Construction, Rehabilitation, and Maintenance brings together the specific knowledge of a bevy of experts and academics in bridge engineering in the areas of design, assessment, research, and construction. The handbook begins with an analysis of the history and development of bridge aesthetics and design; various types of loads including seismic and wind loads are then described, together with fatigue and fracture. Bridge design based on material such as reinforced concrete, prestressed reinforced concrete, steel and composite, timber, masonry bridges is analyzed and detailed according to international codes and standards. Then bridge design based on geometry, such as arch bridges, girders, cable stayed and suspension bridges, is illustrated. This is followed by a discussion of a number of special topics, including integral, movable, highway and railway bridges, together with seismic component devices, cables, orthotropic decks, foundations, and case studies. Finally, bridge construction equipment, bridge assessment retrofit and management, bridge monitoring, fiber-reinforced polymers to reinforce bridges, bridge collapse issues are covered.

• Loads including seismic and wind loads, fatigue and fracture, local effects
• Structural analysis including numerical methods (FEM), dynamics, risk and reliability, innovative structural typologies
• Bridge design based on material type: RC and PRC, steel and composite, timber and masonry bridges
• Bridge design based on geometry: arch bridges, girders, cable stayed and suspension bridges
• Special topics: integral, movable, highway, railway bridges, seismic component devices, cables, orthotropic decks, foundations
• Construction including construction case studies, construction equipment, bridge assessment, bridge management, retrofit and strengthening, monitoring procedures

Section III

Structural analysis

Chapter 5

Bridge structural theory and modeling

A. Pipinato AP&P, Technical Director, Italy

Abstract

Structural analysis and modeling in bridge engineering and design are the themes of this chapter. The first section is dedicated to structural analysis, including equilibrium, compatibility, and constitutive laws equations, with a computational mechanics and theoretical approach. Furthermore, the structural behavior of materials, including nonlinearity, is discussed. The second section is dedicated to structural modeling, including finite element method (FEM) basic principles, modeling elements, modeling methods, material and cross-section details, boundaries, modeling strategies, modeling approaches, and modeling tips subdivided by bridge type.

Keywords

Structural analysis

computational mechanics

equilibrium

compatibility

finite element method (FEM) model

finite element method (FEM) applications

bridge analysis

bridge theory

1 Introduction

The bridge engineering and design process involves a number of disciplines, at the basis of which undoubtedly lies the structural analysis theory. This chapter deals with the most interesting aspects of the structural analysis of bridges. Later, the text focuses on finite element method (FEM) theory and its applications to bridges, to emphasize the importance of this design instrument, commonly used by bridge engineers in their everyday applications.

2 Structural theory

Stresses inside a body generated by external excitations (volume and surface forces) can be obtained using equilibrium equations. Three equilibrium equations relate to the six components of the σ_ij stress tensor for an infinitesimal element in a static state; in the dynamic case, equations of motion are needed, including second-order derivatives of displacement (with respect to time). Considering the geometrical conditions, strains and displacement could be linked by using strain-displacement equations of kinematics expressing the components of strain ɛ_ij by the displacement components (u_i). The constitutive laws exert a material influence on these mathematical relations. The 15 variables are described and can be connected by 15 equations (3 equilibrium equations, 6 kinematics equations, and 6 constitutive equations). To solve the general problem of solid mechanics, two basic methods are available: the displacement method and the stress method. A combination thereof can also be used. In fact, while these methods could be directly applied for simple elastic problems, the discretization procedure is applied nowadays for complex and irregular structural forms and components, as in bridge engineering. This implies a preference for the use of the so-called FEM model, which can subdivide every complex body in...