# FINITE ELEMENT MODELING AND COMPUTATIONS IN THE FIELD OF CIVIL ENGINEERING

Others languages : fr

This collaborative work elaborated by professionals confronted daily to the use of FE methods targets young engineers, who recently graduated from university and often studied exclusively the fundamentals of the FE calculations. Its objective is to answer some recurring questions (such as the mesh size, how to smoothen the peaks, …,) to avoid some issues, and to specify what the FE cannot do. The task force favored to name the project Recommendations and Advices rather than Guide because the document aims to share applications and discuss about finite elements and not create an exhaustive guideline.

#### Table of contents

EDITORIAL Finite Element (FE) calculations – a paradigm shift Words from the Scientific and Tec...

#### The AFGC Editorial

Thierry Kretz was the president of the AFGC Scientific and Technical Counsel when the finite elem...

#### Finite Element (FE) calculations – a paradigm shift

Finite Element (FE) calculations – a paradigm shift It is no exaggeration to say that FE calcula...

#### Preface - Words from the Scientific and Technical Council

Emmanuel Ferrier is the president of the AFGC Scientific and Technical Council. He shares with us...

#### Foreword

#### Introduction

#### PART 1 – THEORETICAL ELEMENTS

#### Chapter A. Introduction

Chapter A. Introduction When performing a FE calculation of a structure, the modeling assumption...

#### A1. General formulation for linear elastic calculations

A1. A general formulation for linear elastic calculations The two main formulations for linear c...

#### A2. The dimensionality of the model

A2. The dimensionality of the model It is very important to simplify the full-size problem to mo...

#### A3. Choosing the finite elements

A3. Choosing the finite elements Choosing the element is an important step. The goal is to selec...

#### A4. Interaction between the structure and its environment

A4. Interaction between the structure and its environment Taking into account the interactions b...

#### A5. Estimation of the quality of the approximated numerical solution

A5. Estimation of the quality of the approximated numerical solution The difference between the ...

#### Chapter B. Structural Dynamics

Chapter B. Dynamics For many applications such as seismic calculations, collisions, vibrations… ...

#### B1. Analysis based on a modal search

B1. Analysis based on a modal search A reminder of the concept of simple oscillator – Concept of...

#### B2. Analysis based on a direct temporal integration

B2. Analysis based on a direct temporal integration Schemes of integration Main Principles: T...

#### B3. Considering damping

B3. Considering damping The damping of a structure’s vibration is related to dissipation phenome...

#### B4. Specificities of the seismic analysis

B4. Specificities of the seismic analysis Spectral response – Specific case of earthquakes The ...

#### Chapter C. Static non-linear calculations

Chapter C. Nonlinear Static calculations Nonlinear calculations are generally time-demanding: a ...

#### C1. Mechanical non-linear problems

C1. Mechanical non-linear problems Description of possible non-linearities The non-line...

#### C2. Why performing non-linear calculations

C2. Why performing non-linear calculations As in many areas of physics, it is only reasonable to...

#### C3. Implementation

C3. Implementation The correct method consists of always proceeding step by step so that non-lin...

#### C4. Convergence issues? Symptoms and solutions

C4. Convergence issues? Symptoms and solutions As opposed to linear elastic calculations, non-li...

#### Chapter D. Civil Engineering

Chapter D. Civil Engineering D.1 Civil engineering materials D.1 Civil engineering materials D...

#### D1. Civil engineering materials

D1. Civil engineering materials The objective of this chapter is to highlight the peculiarities ...

#### D2. Different categories of structural elements

D2. Different categories of structural elements Here are presented the peculiarities of these e...

#### D3. The different construction phases

D3. The different construction phases Studying the phases of construction has two objectives: ...

#### Chapter E. Typical post-treatment in Civil Engineering

Chapter E. Typical post-treatment in Civil Engineering Introduction In civil engineering there ...

#### E1. Generalities

E1. Generalities The different post-treated quantities may change significantly according to the...

#### E2. Quantities in Dynamics

E2. Quantities in Dynamics Time-dependent analyses Post-processing of time-dependent qu...

#### E3. The specific case of reinforced concrete

E3. The specific case of reinforced concrete Overview of the common methods for designing th...

#### Chapter F – Geotechnical calculations

Chapter F – Geotechnical calculations Introduction Conventional methods for the design and dim...

#### F1. Geometric aspects

F1. Geometric aspects One of the advantages of the FE method is the possibility of describing t...

#### F2. Material non-linearities

F2. Material non-linearities In geotechnics, it is very rare to be able to study a structure ex...

#### F3. Soil-structure interactions

F3. Soil-structure interactions Geotechnical structures often combine layers of soil with metal ...

#### F4. Hydraulic effects

F4. Hydraulic effects Hydromechanical coupling Another peculiarity of geotechnical calc...

#### F5. Uncertainties and recommendations

F5. Uncertainties and recommendations Uncertainties There are many sources of uncertai...

#### F6. Normative aspects: Principles of the Eurocode 7

F6. Normative aspects: Principles of the Eurocode 7 Numerical modeling always had a particular r...

#### F7. Modeling in Dynamics

F7. Modeling in Dynamics Because of the continuous and unconfined nature of geomaterials, the...

#### F8. Characteristic scales

F8. Characteristic scales Firstly, to frame the discussion about soil dynamics problems, it is n...

#### PART 2 – USEFUL ELEMENTS

#### Chapter A. Understanding the finite elements

Chapter A. Understanding the finite elements A.1. What does a finite element software do? Exampl...

#### A1. What does the software do in a finite element calculation? The example of beam structures

A1. What does the software do in a finite element calculation? The example of beam structures Th...

#### A2. What is a finite element?

A2. What is a finite element? The resolution of the efforts in the elements is carried out follo...

#### Chapter B. Computational objectives and necessary characteristics of the tool

Chapter B. Computational objectives and necessary characteristics of the tool Creating a finite...

#### B. Calculation objectives and necessary tool characteristics

B. Calculation objectives and necessary tool characteristics Creating a finite element computat...

#### B.7 Organization of the calculation

B.7 Organization of the calculation This is an essential step to be carried out at the beginnin...

#### Chapter C. Good practices to create a model

Chapter C. Good practices to create a model The different levels of analysis and the complexity ...

#### C1. Input data and units

C1. Input data and units The input data must be consistent, whether these values are defined in ...

#### C2. Modeling of the main elements

C2. Modeling of the main elements C.2.1 Creating the geometry The first stage of modeling consi...

#### C3. FE and meshing

C3. FE and meshing C.3.1 Types of finite elements First and foremost, the user of FE software m...

#### C4. Modeling the non-structural elements or equipment

C4. Modeling the non-structural elements or equipment Non-structural elements and equipment are ...

#### C5. Boundary Conditions

C5. Boundary Conditions C.5.1 General case The boundary conditions are determined by the degree...

#### C6. Connections - links – assembly

C6. Connections - links – assembly C.6.1 Releasing the bars/springs/degrees of freedom In all m...

#### C7. Offsets

C7. Offsets Most finite element software offer several options to define a beam on a fiber othe...

#### C8. Composite Sections (Beams/Slabs)

C8. Composite Sections (Beams/Slabs) Composite sections are made up of the assembly, rigid or e...

#### C9. Materials

C9. Materials Part 1 Chapter 4 is dedicated to civil engineering materials and their specificiti...

#### C10. Specific behavior in shear and torsion

C10. Specific behavior in shear and torsion In general, it should be noted that beam element mod...

#### C11. Modeling the loading

C11. Modeling the loading As explained in chapter E, it is important to always verify for each l...

#### C12. More about solid elements

C12. More about solid elements The principles stated for 2D modeling remain applicable in 3D, in...

#### C13. More about non-linear calculations

C13. More about non-linear calculations This paragraph deals with non-linearities related to the...

#### C14. More about prestressed concrete

C14. More about prestressed concrete The proper modeling of prestressing requires using specific...

#### C15. More about phased calculations

C15. More about phased calculations The reader may also refer to Part 1 - D.3 Construction Phase...

#### C16. More about dynamic and seismic calculations

C16. More about dynamic and seismic calculations The dynamic solicitations generate inertial and...

#### Chapter D. Analysis and processing of the results

Chapter D. Analysis and processing of the results D.1 General information about numerical calcu...

#### D1. General information on numerical calculations

D1. General information on numerical calculations D.1.1 Calculation time Computation time (in t...

#### D2. Load combinations

D2. Load combinations D.2.1 Combinations and envelopes Recall that using a load combination co...

#### D3. Data processing

D3. Data processing D.3.1 Stresses/Deformations or Internal forces It is important to define wh...

#### D4. Normative verifications: the behavior of reinforced concrete elements

D4. Normative verifications: the behavior of reinforced concrete elements D.4.1 Reinforcement ma...

#### D5. Understanding and analyzing the peaks (case study about concrete)

D5. Understanding and analyzing the peaks (case study about concrete) The smoothing referred to ...

#### D6. Understanding and analyzing the peaks (case study about steel assembly)

D6. Understanding and analyzing the peaks (case study about steel assembly) The results of a cal...

#### D7. Further information specific to dynamic calculations

D7. Further information specific to dynamic calculations D.7.1 Total mass verification In the c...

#### Chapter E. How to ensure quality?

Chapter E. How to ensure quality? Below are some simple advice to assess the quality of the fini...

#### E1. Starting with a new software

We propose below some simple advice to deploy a quality approach in finite element calculations. ...

#### E2. Model validation using self-checking

E2. Model validation using self-checking Before exploiting the model results, several verificati...

#### E3. Traceability and group work

E3. Traceability and group work While there are projects where a single engineer will do all the...

#### Chapter F. How to properly present the finite element calculation note?

Chapter F. How to properly present the finite element calculation note? This paragraph introduce...

#### F. How to properly present the finite element calculation note?

F. How to properly present the finite element calculation note? This paragraph provides the mini...

#### PART 3 – EXAMPLES AND COMPLETE CASE STUDIES

#### EXAMPLES AND COMPLETE CASE STUDIES

This part contains modeling examples for simple and more complex objects. They are presented as a...

#### Example A - Modeling a complex high-rise building

Example A - Modeling a complex high-rise building Franck DUBOIS - Structures Engineering ...

#### Example B - Mixed and Steel Girders

Example B. Mixed and Steel Girders The subgroup responsible for these examples is still workin...

#### Example C - Beam Grillage Modeling

Example C - Beam Grillage Modeling Benjamin Tritschler (Arcadis) - Transverse Bending of a M...

#### Example D - Simple example: modeling of a Br wheel

Example D - Simple example: modeling of a Br wheel The purpose of this example is to show the di...

#### Example E - Transverse bending of a prestressed concrete box girder

Example E - Transverse bending of a prestressed concrete box girder Author : Jean-Paul Deveaud...

#### Example F – Dynamic calculations of tanks

Example F – Dynamic calculations of tanks Coming soon... a little patience required. Author: Gi...

#### Example G – Cable-stayed bridges

Example G – Cable-stayed bridges Coming soon... a little patience required.

#### Beam Grid Example

Beam Grid Example 1. Beam grid The beam grid is a generally horizontal structure consisting of ...

#### Contribution to the beam grillage analysis

Contribution to the beam grillage analysis Author: Pierre PERRIN – Assistant director of the bri...

#### Transverse bending of a multi-beam bridge

Transverse bending of a multi-beam bridge Author: B. Tritschler (Arcadis) – April 29th, 2020 1....

#### Example of a beam grillage calculation according to different methods - Part 1

Example of a beam grillage calculation according to different methods Comparison of the results...

#### Example of a beam grillage calculation according to different methods - Part 2

Example of a beam grillage calculation according to different methods Comparison of the results...

#### Example of a beam grillage calculation according to different methods - Part 3

Example of a beam grillage calculation according to different methods Comparison of the results...

#### Practical application of smoothing

Practical application of smoothing Example of the Br wheel in Handbook 61, title II Finite Elem...