Design of Bridges

Module aims

  • To introduce students to the design and construction of bridges. This module covers the structural behaviour of the main longitudinal and transverse bridge typologies, the fundamental design principles, and main construction procedures for short, medium and long span bridges.
  • To provide the students with the minimum knowledge threshold to be able to participate in the Conceptual Project on Bridges, and the Bridge Detailed Project, offered as part of the MSc programme over the summer term. 

Learning outcomes

On successfully completing this course unit, students will be able to: 

  •  Develop the conceptual design for short, medium and long span bridges.
  • Understand the structural behaviour of the different longitudinal and transverse bridge types.
  • Select appropriate longitudinal and transverse schemes for particular cases.
  • Determinate the actions to be considered for the design of a bridge according to Eurocodes.
  • Propose conventional models for structural analysis of bridges.
  • Design a concrete or steel composite bridge deck of medium span according to Eurocodes.
  • Selection of bearings, joints, piers and abutments.
  • Select the appropriate construction method.

Module syllabus

  • The structural behaviour and design principles for the main longitudinal (such as beams, portal frames, arches, cable-stayed bridges, and suspension bridges) and transverse (such as beams, slabs, and box girders) bridge typologies.
  • The preliminary design of prestressed concrete composite bridge decks, and steel-concrete composite bridge decks.
  • The design of different bridge components and elements (such as parapets, waterproofing, drainage, bearings, joints, abutments, piers, etc.).
  • The main bridge construction procedures.  





Introduction to the module; aims, objectives and learning outcomes, contents, and schedule, assessment, general references; bridge infrastructure, functions and design requirements; platform types; waterproofing and surfacing

parapets; drainage and services, and bearings; Joints, piers and abutments

bridge design codes and standards.



Actions (pedestrian, road, railway bridges)



Transverse schemes; beams; section types in structural concrete decks (precast and in-situ construction; T-beams; U-beams; transverse spacing)

Section types in composite decks

Advantages and disadvantages of this transverse scheme

Transverse load distribution

Structural behaviour under uniform distributed loads

Structural behaviour under point loads

Transverse schemes. Slabs

Section types (solid and voided slabs)

Advantages and disadvantages of this transverse scheme

Transverse load distribution

Voids geometry

Transverse sections in both variable-depth decks variable-width decks

Diaphragms at support sections

Transverse schemes. Box girders

Sections types for prestressed concrete, composite, and steel decks

Advantages and disadvantages of this transverse scheme

Structural behaviour under uniform distributed loads

Structural behaviour under point loads

Effective width




Longitudinal schemes. Beams


Statically determinate beams (uniform depth, fish-belly shape, Gerber; advantages and disadvantages)

Statically non-determinate beams (constant/variable depth; advantages and disadvantages)

Appropriate transverse types for different span lengths

Geometry of continuous bridges (constant/variable depth)

End spans in continuous bridges

Coupled torsion and bending responses in curved beams

Longitudinal schemes. Portal frames

Advantages and disadvantages of this longitudinal scheme


Longitudinal schemes. Arches

Span ranges



Superior deck arch bridges (links between elements; geometry; arch cross-sectional section; rigid and deck-stiffened arches)

Inferior deck arch bridges / Tied arch bridges / Bow strings (behaviour; stays / hangers)



Longitudinal schemes. Cable-stayed bridges

Span ranges


Structural behaviour under permanent and live load

Efficiency of cable-stayed bridges

Longitudinal and transverse stay cable arrangement

Deck cross-sectional sections (for different stay cable configurations; for different spans)

Tower types

Configuration of cable-stayed bridges with two, three and multiple spans

Ernst modulus

Stay cables

Longitudinal schemes. Suspension bridges

Introduction to FE models for structural analysis of bridges

Grillage models for beams, slabs and box girders




Pretensioned and postensioned concrete decks



Composite decks with steel beams and concrete slabs



Design of Bridges



Construction of bridges

In-situ and precast construction

Falsework, gantries and self-launching gantries

Span by span construction

Cantilever construction

Transverse launching

Longitudinal launching


Redistribution of internal forces due to loads which are applied on temporary structural schemes in concrete bridges.



(if there is a 10th session available, the material will be divided in 10 sessions)


Teaching methods

A combination of lectures and tutorials.


Assessment is via examination.

Reading list

Module leaders

Dr Ana Ruiz-Teran