solution for bridges design and analysis

Solution for Bridges Design and Analysis

The state-of-the-art technology for the civil

engineering world

Main Features• Concrete Creep and Shrinkage• Bridge layout modeling (in plan and

elevation view)• Utilities for generating common bridge sections

and layout design• Geometric and finite element model generation

with both Beams (1D) and Solid elements (3D)• Loads Generation

• Overloads• Moving loads (vehicle’s editor)• Utility for Prestressing forces input• User loads

• Automatic Loads combination• Simulation of the construction process

Concrete Creep and Shrinkage• Effects of Creep and Shrinkage relative to concrete maturity can be easily

considered• Allows to obtain the deformed

shape as well as the forces,

moments and stresses in the model

Bridge Layout Modeling• This utility allows to generate the geometry and the finite element

model of the bridge from common engineering blueprints. It works as a “layout program”, allowing to define the layout design in both plan and elevation views

• The procedure used for the bridge layout definition is the following:• Definition of the mileage points (MP’s) that represent the

structure axis• Definition of plan and elevation layout

• All the input data to create the layout and their corresponding results can be later retrieved with a single command (~CFGET)

Bridges Layout in Plan View• In plan view, the mileage points line is a succession of user-

defined stretches:• straight segments • circular arcs• clothoid arcs

Caso R = R : Defin ition of the section elem entsi f/

(x ,y )i i

(x ,y )f f

R

i

f

s = s + Long

R

ii

s x

y C lothoid axis

cl

cl

Bridge Layout in Elevation View

• In elevation view, the mileage points line is a succession of user-defined stretches:• straight segments • parabolic arcs

Vertical fillet

s i

s f

i

f

f

L

T

z f

z i

s

Stra igh t sec tion

Stra igh t sec tion

P arab o lic fille t

s

si f

i i

z

Bridge Cross Sections

Bridge Section Types

R ectangular section

Trapezoidal section

Trapezoidal section w ith flanges

Polygonal section w ith tw o bends

Polygonal Asym m etric w ith tw o bends Note : The upper line (deck) is a lwayshorizontal. The slope m ust be laterdefined w ith the section ’s bank.

B

D EPTH

RS

BTO P

BBO T

D EPTH

TTO P

TS

D EPTH

BTO P

BM

BBO T

TTO P

TBO TTF

TBO T BBO T

BM 2

BM 1

BTO P

D EPTH

TTO P

TMPS

BBO TR

BM 2R

BM 1R

BTO PRBTO PL

BM 1L

BM 2L

BBO TL

D EPTH L

TBO TL

TM L

TBO TR

TTO PR

TM R D EPTH R

axis

PATri-cell box section definition

a1

p11

b1

a2

t 22 t 21

t 11

p21p22

s31

1

1

p121

11

t 31

hL

vL

y

z

vC L

hC L

hC U

vC U

t 41

vU vU r

hU hU r

a /20

vC U r

hC U r

hC Lr

vC Lr

• This module includes a library of typical bridge cross sections, which are defined by the outline of the section:• Slab cross sections• Box cross sections

Slab Concrete Sections• It’s possible to define holes• The sections can be symmetric or asymmetric• Sections and the hole diameters might vary along the bridge

Box Sections with Variable Depth• Any generic box section can be easily defined• All the necessary input parameters can be introduced either by

menu or using the corresponding command (allows performing a parametric design of cross sections, creating macros, etc).

Tri-cell box section definition

a1

p11

b1

a2

t 22 t 21

t 11

p21p22

s31

1

1

p121

11

t 31

hL

vL

y

z

vC L

hC L

hC U

vC U

t 41

vU vU r

hU hU r

a /20

vC U r

hC U r

hC Lr

vC Lr

Assigning Attributes

Trans = 0Trans=1

Section's transition definition

• For the automatic generation of the geometrical and FEM model, the defined cross sections are assigned to the mileage points (MP’s) forming the bridge layout

• The transition of sections between MP’s can be defined using straight segments and splines

Assigning Attributes• The cross sections may have the following attributes:

• Offsets• Banks• Skew• Hollow or solid sections

z

y

Zoffs

Yoffs

MP,s line

Bank (Rotation's center P) P

Model Generation• Once the layout and cross sections are defined the geometrical and FEM

model generation can be automatically performed by the program

Model Generation

Beam element model (shape option)

Solid element model

• Just by specifying an element type, a Solid finite element model or a Beam finite element model can be generated

Model Generation• From this version on, generation of Box Bridges using SHELL elements is

supported

Model Generation• Allows for a trial and error process using beam elements (less CPU

and engineer time).• Automatic discretization of the beam element cross- sections into

points and tessella (allows for analyzing the section’s internal behavior using beam elements)

• More accurate design can be performed using SOLID elements by only changing the element type and running the analysis again.

Suspension Bridges WizardSuspension Bridge Generator windows can

generate 3D models for:• Concrete Suspension Bridges

(with a CivilFEM bridge section)

• Steel Suspension Bridges(with a CivilFEM 3D steel truss pattern)

• Generic Suspension Bridges(with a CivilFEM generic cross section)

• Mixed section, two types of section:- Concrete slab over I-section steel beams - Concrete slab over a steel box section

Suspension Bridges Wizard• By using this Wizard it is possible to easily introduce the

number of segments and the corresponding data to generate the entire bridge model for both 3D beams and solid elements.

Suspension Bridges Wizard• Concrete

Suspension Bridges Wizard• Both concrete and steel truss suspension bridge models are

automatically generated for any generic configuration by just inputting a few parameters.

• Steel

Suspension Bridges Wizard

• Steel

Suspension Bridges Wizard• Any generic cross section from library and/or any 2D defined

using CivilFEM with ANSYS meshed drawing (capture utility) can be used as a bridge cross section

• Optimization of the geometry

and initial tensions of cables


Bridge section is composed of a concrete slab over I-section steel beams:

• Mixed Section (type 1)

nB bB

hBeam

tFLtWeb

yz

bSlab/2

bSlab

tSla

bfSRfSL

Suspension Bridges Wizard• Mixed Section (type 1)

Suspension Bridges Wizard• Mixed Section (type 1) Example


Bridge section is composed of a concrete slab over a steel box section:

• Mixed Section (type 2)

bSlabfSL fSR

hBox

tSlab

tboxL tboxRtboxB

alphaLalphaR

yzbSlab/2

Suspension Bridges Wizard• Mixed Section (type 1)

Suspension Bridges Wizard• Mixed Section (type 2) Example

Supported Bridges Wizard• Same parameters used in suspension bridges are also employed

here, but only the bridge deck is generated.

Suspension Bridges Wizard• Supported Bridge Examples

Cable Stayed Bridge Wizard

• Generation window


• Model generation• Cable arrangements:

HARP TYPE FAN TYPE

z

x

XL1XL2XL...

XR1 XR2 XR...

ZB1

ZB2

ZT1

ZT2

ZT...

ZB...

ZT3

(XB, ZB)

(XT, ZT)

z

x

XL1XL2XL...

XR1 XR2 XR...

ZB1

ZB2

ZT1

ZT2

ZT...

ZB...

ZT3

(XB, ZB)

(XT, ZT)

z

x

XL1XL2XL...

XR1 XR2 XR...

ZB1

ZB2

ZT1

ZT2

ZT...

ZB...

ZT3

(XB, ZB)

(XT, ZT)

z

x

XL1XL2XL...

XR1 XR2 XR...

ZB1

ZB2

ZT1

ZT2

ZT...

ZB...

ZT3

(XB, ZB)

(XT, ZT)

Cable Stayed Bridge Wizard• Model generation

• Towers: Unlimited in number, variable cross sections, vertical or inclined with multiple cable arrangements


• Model Generation

• Different boundary conditions and connection between towers and deck

MN

MX

XY

Z

Cable Stayed Bridge Wizard• Nonlinear Construction Process

Analysis:

XY

ZXY

ZX

Y

Z

Cable Stayed Bridge Wizard• Nonlinear Construction Process Analysis:


Analysis:• Cable force optimization: Deflection


Analysis:• Cable force optimization: Bending

Moment

Arch Bridge Wizard• Arch Bridge Generator (Beam

Model)

Arch Bridge Wizard• Depending on the position of the bridge deck

compared to the arch, there are different cases:

Arch Bridge Wizard

• Beam Model

Arch Bridge Wizard

Arch Bridge Wizard

• Shell Model

Bridge Components• CivilFEM with ANSYS allows a detailed analysis

of piers, cross bracings, diaphragms, etc.

Special Features• Any of the bridge parameters (layout, sections, dimensions, etc.)

can be easily parameterized by the user, allowing very fast sensitivity analysis, making use of some advanced features:• Log files

the program stores in a file all the orders executed by the program during a job. This file can be edited by the user at any time and the model can be executed again by just reading it

• Macros (APDL)

• Customization: users are able to create their own windows, commands, etc, customizing the program as much as possible to their own needs

Loads Generation• CivilFEM automatically

generates the loads corresponding to the various load hypotheses over a 2D or 3D structure, such as:• Moving loads (traffic loads)• Surface loads (Overloads)• Prestressing tendons

• Any kind of “user defined” loads• “Smart” load combination of all

the load steps generated during the analysis

Loads Generation (Traffic Loads)

Vehicle library: just choose the vehicle and the corresponding properties are automatically

defined

Property window

• With the vehicle editor it is possible to create, import from library, modify, copy, delete and list vehicles


• Allows considering the braking or starting load (horizontal) for each vehicle wheel

• One or more vehicles can be used at the same time


• Two different types of vehicles: Rigid (truck) or flexible (train, adaptable to the path)

• User friendly path definition: road surface and road axis are automatically detected by the program

Trajectory definition (R igid veh icle)

MP,s

line com ponents

Vehicle trajectory

Assembly the bridges nodes and elem ents, where the loads are applied

Dist

The tangency occurs in the point (xLoc, yLoc) of the vehicle

Trayectory defin ition ( )adaptable to the trajectory

KP,s

Lines com ponent

Vehicle trayectoryAssembly the bridges nodes and elem ents, where the loads are applied

Loads Generation (Surface Loads)

Definition of surface loads

KP,s Lines component

Overload grid

s1

d1

d2

dm

Assembly with the bridges nodes and elements over which the surface load will be applied

• Definition of an overload grid over the deck• Automatic load generation and combinations of all possible load

case scenarios

Loads Generation (Prestressing Cables)

• Definition of points along the cable’s path (automatic adjustment of the points using splines)

• Introduce the tensile force at specific locations in the tendon’s path• Automatic transfer of the cable action to the structure:

• the program calculates an equivalent system of forces at each node of the element that equilibrate the system

3D spline generation

P

P

P P

P 1

2

k+2 k+1

N

P' 1 P' N

P k

Transmision of the cable actions to the model

OP

xR

R

MRy

z

MRz

xMR

c.d.g.R

y

Kfx

Kfy

Kfz

T1

T2

1

2

Loads Generation - Notes

• In addition to the automatic loads generation explained here, any other “user-defined” load can be applied to the structure such as wind loads, snow, seismic (automatic definition of spectrum according to codes) and so on.

• The automatic load generation feature, although is inside the bridges module, can be applied to any other type of structure simply by defining the surface over which the loads are to be applied.

Dynamic Analysis• A transient analysis can be automatically performed. • It is also possible to input speeds in the definition of the

moving loads

Load Combination - Example• Where must be located the two engines to obtain the

maximum stresses at point P?• What is the maximum bending moment at section A-A ?• What are the corresponding concomitant values?

P

A ----- A

Load Combination• In the bridge analysis process, a great number of load

steps are generated, which later on have to be combined looking for the worst case scenario. CivilFEM includes functionalities that can automatically handle all possible load cases

• Obtains the envelop that considers the worst case scenario for each structural point by specifying a target

• Concomitance at both global and element levels• Variable load coefficients can be defined • Combining the moving loads (traffic loads)

• The program automatically combines them as an “incompatible” load (which is the same as saying that a vehicle can only be located at one position at the same time)

Load Combination• Combining the surface loads (overloads)

• CivilFEM will automatically combine them as a “compatible” load (these loads will then be allowed to be located at any possible position over the surface)

To obtain the envelop of maximum vertical displacements at all nodes

OBJECTIVE:

Load Combination• Combining the prestressing cable loads

• The program automatically combine them as an “addition” load (adds all the loads and apply them at the same time)

• Combining “user-defined” loads• The same procedure is applied simply by defining the

combination rule to be used (compatible, incompatible, addition, selection, etc) to find the combined results

Checking & Design• Serviceability Limit State

• Cracking checking according to codes

Checking & Design• Ultimate Limit State

• Check and design of the bridge reinforcement according to codes, taking into account all the loads applied to the structure.

Simulation of Construction Process

Normal Procedure

• The bridges module allows to simulate multiple types of construction process


• Cantilever construction

Y

X

Puente construido mediante dovelas yuxtapuestas: Situación después del step #3

Y

Z

Pile Section: A reaU , I , I , A reaB, I ,I , HyyU

z

Bridge p lant

N ot bu ilded zone

10 11 12 13

Sections

12

Steps

Live cab le

7 8 9 14 15 161 2 3 4 5 6

23

112

3

H

Live pile support

N ot live support

zzU yyB zzB

Pile section axis

Bridge section axis


12345

Proceso constructivo de un puente empujado

123

En la etapa in icia l nacen cuatro seccionesy solo una de e llas está "em pujada" (la una)

4

1234

En la segunda etapa se em puja una nueva sección (la 2), la sección 1 ha llegadoa un apoyo interm edio que al final de la construcción ocupará la 4

1234

En la tercera etapa nace la sección 5, perono se em puja n inguna nueva

5

En la ú ltim a etapa el puente está com pleto. Las secciones 4 y 1 a lcanzan sus apoyos defin itivos.

12345 12345 12345 12345

En la cuarta etapa el puente está com pleto, pero tan solo se em pujandos secciones..

6

6

• Push launching

Bridge Postprocessing• CivilFEM with ANSYS performs a wide range of

postprocessing calculations: load combinations, results displays, check and design processes, etc.

Bridges and Nonlinearities Module

solution for bridges design and analysis

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