Istanbul Technical University

Faculty of Mechanical Engineering

Solid Mechanics Department

Istanbul Technical University

The Faculty of Mechanical Engineering

PROJECT

DYNAMIC EXPLICIT ANALYSIS OF RUBBER BALL HITTING CONCRETE WALL

MAK 525E Finite Element Methods

Submitted by : Begüm Derebay 503101511

Submitted to : Prof. Dr. Ata Muğan / Dr. Emin Sünbüloğlu

Due to :24-May-2011

INFORMATION ABOUT ANALYSIS BEFORE THE RESULTS

Two parts are generated for this analysis.

1. Concrete wall

2. Rubber ball

Material properties entered as below:

1. Concrete

Density : 0.14

Young’s Modulus: 170000

Poisson’s Ratio: 0.3

2. Rubber

Density: 0.0001

Hyperelastic material property was selected and below values were entered as data:

Polynomial

Coefficients:

C10: 500 C01: 100 D: 0.0001

Rubber material was assigned to BallSection (Type: Shell / Continuum Shell, Homogeneous)

Shell thickness: 1

Concrete material was assigned to WallSection. (Type: Solid, Homogeneous)

BallSection assigned to the part named Rubber Ball and ConcreteSection assigned to the part named

Concrete Wall as well.

After assembly process, in the Initial Step, boundary condition for concrete wall was given for the

bottom surface fixed as Encastre. Velocity is given for the rubber ball as V1: 800, V2= 800, V3= -1200.

In the Dynamic Step Field Output Request for the whole model domain, and a frequency of every 3E-

005 units of time, output variables were selected. History Output Request 1 is created for interaction

domain and History Output Request 2 for the whole model domain.

Interaction was created as Dynamic, between outer surface of the rubber ball and front surface of

the concrete wall. Kinematic contact method was chosen for the analysis.

Interaction property option is setted to Tangential Behavior and Frictionless.

With a approximate global size of 0.8 concrete wall was meshed.

With a approximate global size of 0.3 rubber ball was meshed.

Result of the analysis is as below:

Undeformed:

First Analysis Deformed

Stress Distribution

Contours on undeformed shape

External work for the whole model:

Strain energy for the whole model

Total area in contact

Contact pressure distribution

Contact shear distribution

Strain components at integration points (Kinematic Strain)

LE11

LE22

LE33

Reaction forces

Stress

S11

S22

S33

If mesh size is changed (Rubber Ball seed size cahnged to 0.1):

CPRESS

LE13

INTERNAL ENERGY

KINETIC ENERGY

STRAIN ENERGY

EXTERNAL WORK