ENT 251/4 – Solid Mechanics
Laboratory Module
BENDING ANALYSIS (ETBX)
1.0. OBJECTIVE
To provide a quick overview on how to use ETBX, an engineering toolbox in Bending
Analysis
2.0. INTRODUCTION & THEORY
EngineersToolbox (ETBX) is a graphics-based rapid analysis tool for engineers. ETBX
provides fast, interactive solutions to a wide range of engineering problems using an
integrated library of computational modules.
The core of ETBX functionality is provided by ETBX computational modules. ETBX
modules help guide the engineer through an analysis by providing labeled input fields, text
descriptions, and graphical schematics. More importantly, ETBX modules provide the data
and formulas required to conduct the analysis. ETBX modules consist of:
1. Solid Mechanics
2. Fluid Dynamics and Heat Transfers
3. Dynamic and Controls
4. Fatigue and Fracture Mechanics
This lab, we only discuss on how to use ETBX in Solid Mechanics Module
2.1 Solid Mechanics Module
The ETBX software can be started by double clicking the ETBX icon on your desktop. Small
menus will appears on your desktop as shown in Fig. 1
Fig. 1 ETBX menu
20
ENT 251/4 – Solid Mechanics
Laboratory Module
2.2. Uniform Beam Analysis
The Uniform Beam Analysis module calculates the vertical shears, moments, slopes, and
displacements of a transversely loaded uniform beam with various end supports. The
module also calculates the natural frequencies and mode shapes of the beam. The module's
closed-form equations are based on the following assumptions:
 The cross section is uniform.
 The beam is of homogeneous material with the same elastic modulus in tension and
compression.
 The beam is straight.
 The beam is long in proportion to its depth.
 The maximum stress does not exceed the proportional limit.
By double clicking uniform beam analysis link will bring the menu as shown in Fig. 2(a)
(b)
(a)
Fig. 2 Uniform Beam Analysis menu and load condition
The load conditions are limited to (1) concentrated force, (2) concentrated moment, and (3)
distributed force as shown in Fig. 2(b). The section beam and material properties menu are
also provided in order to match the problem of simple beam. (See Fig. 3)
21
ENT 251/4 – Solid Mechanics
Laboratory Module
Fig. 3 Beam sections and material properties database.
2.3. General Beam Analysis
The General Beam Analysis module performs a finite element analysis of a general beam
with multiple sections and supports subject to transverse loads. The module calculates
static displacements, rotations, shears, moments, and stresses; and natural frequencies and
mode shapes. The beam problem is defined using multiple nodes and elements as shown in
Figure 1. The beam can be split into as many as 19 discrete elements of varying lengths,
and with independent boundary conditions, cross-sectional properties, and materials.
Results are output in both text and graphic form.
The General Beam Analysis title panel shown in Fig. 4 provides the primary interface for
specifying the solution type, navigating between input and output panels, viewing the beam
model, and running an analysis. The title panel is partitioned into 3 groups:
 Analysis Input Group
Contains the basic controls for defining global analysis parameters, editing the beam
model, and post-processing results.
 Graphics Options Input Group
Contains controls for customizing the display of the analytical model.
 Beam Design Display
Contains a graphical view of the analytical model, including beam geometry,
boundary conditions, and applied loads
22
ENT 251/4 – Solid Mechanics
Laboratory Module
Fig. 4 General Beam Analysis.
3.0. EQUIPMENT
Computers and ETBX program in the computer lab
3.0. PROCEDURE
5.1.
5.2.
5.3.
5.4.
5.5.
For case study, sketch your own free body.
Choose the beam constrains appropriately.
Determine the appropriate loads according to your case.
Determine the beam section and material properties.
Calculate and see the results in graphics, scatter plot and tabular outputs.
23
ENT 251/4 – Solid Mechanics
Laboratory Module
5.0. CASE STUDY
5.1. Uniform Beam Analysis
Case 1 Simply supported beam with concentrated force
This is example 6.1 in your text book and compares the result.
Case 2 Simply supported beam with concentrated moment
This is example 6.2 in your text book and compares the result.
Case 3 Simply supported beam with distributed load
This is example 6.3 in your text book and compares the result.
Case 3 A cantilever beam and distributed load
24
ENT 251/4 – Solid Mechanics
Laboratory Module
This is example 6.4 in your text book and compare the result.
Case 4 Simply supported beam with combination of loads
This is example 6.6 in your text book and compare the result.
5.2. General Beam Analysis
Case 1 Beam with combination of load and supports
20 kN/m
D
C
2.0 m
2.0 m
2.0 m
2.0 m
Case 2 Beam with combination sections and loads C
20 kN/m
20 kN
30 kN/m
70 kN.m
I =1.0
2.0 m
I =0.7
1.0 m
I =1.0
1.0 m
2.0 m
25
I =0.7
1.0 m
1.0 m
ENT 251/4 – Solid Mechanics
Laboratory Module
Report Example
Name
Matrix No
:
:
___XXX YYY____________________
___0XXX_______________________
Date : _25/0906____
CASE STUDY: BENDING
CASE:
The maximum bending stress occurs in the handle of cable cutter.
Free Body Diagram:
0.3 N/mm
200 N
C
RAX
RAY
FBC
26
ENT 251/4 – Solid Mechanics
Laboratory Module
MODULE OF SOLID MECHANICS:
Uniform Beam Analysis

General Beam Analysis
BEAM DESIGN
Fig. 1 Original beam design
BEAM ANALYSIS
Fig. 2 Original beam analysis
27
ENT 251/4 – Solid Mechanics
Laboratory Module
NEW BEAM DESIGN
50 mm
Fig. 3 New beam design
Fig. 4 New beam analysis
DISCUSSION
Explain how the new design provides more benefit to the original beam.
28
ENT 251/4 – Solid Mechanics
Laboratory Module
Appendix
Cases that can be considered
Case of Pin
Case of Connecting Rod
Case of Chair
29