HW 2 (1) Visit Monsanto (http://www.monsanto.com) again and Google to find various information about internal factors of Monsanto. (2) Based on the information, perform your own internal audit for Monsanto. You do not need to perform financial analysis for this assignment. If you perform the internal audit, you will find strengths and weaknesses of Monsanto. (3) List the strengths and weaknesses of Mondanto. Then, explain why you think so. Note: Strengths and Weakness are SW of SWOT analysis. We will use strengths and weaknesses in the last module later. 1 Class Today • Print notes and examples • Trusses – Definition – Working with Trusses – Truss Analysis • Example Problems • Group Work Time http://www.mst.edu/~ide50-3/printable_notes/13_Trusses.pdf http://www.mst.edu/~ide50-3/printable_notes/13_Trusses_examples.pdf …these are cool trusses Norman Foster Sainsbury Centre Santiago Calatrava Turning Torso Shigeru Ban Japanese Pavilion KMR … be inspired! 3 Renzo Piano Kansai International Airport Rem Koolhaas The Shenzhen Stock Exchange KMR So what are trusses? http://bridgehunter.com/story/1109/ http://www.americanpoleandtimber.com/img/wood-timber-trusses-park-BIG.jpg http://www.hndszj.com/eng/uploads/201008101822313.jpg Trusses are … • Structures designed to support loads: − Will transmit loads through the joints of the structure − Will ultimately transmit loads to the foundation • Cost effective in design because: − Weight is minimized (weight of members is typically light compared to loads carried, so it is often neglected) − Strength to weight ratio is maximized Image copyright 2013, Pearson Education, publishing as Prentice Hall Working with Trusses: Assumptions • All loads are applied / transmitted at joints • All members are joined by pin connections • Consist entirely of two-force members (review section 5.4) • Can contain zero-force members Image copyright 2013, Pearson Education, publishing as Prentice Hall Zero-force Members What are zero-force members? • Structural members that carry no force Why do we use them? • Used to provide stability – During construction – If (intermittent) loading of the truss changes • Shortens chord length and increases buckling capacity of compression members 7 Zero-force Members: Case 1 Zero-force Members: Case 2 10 http://www.tatasteelconstruction.com/static_files/Images/Construction/Reference/ architectural%20studio/elements/Structural%20steel%20trusses/j2.jpg http://www.tboake.com/SSEF1/rose2.shtml http://sluggyjunx.com/rr/georgetown_branch/gallery/04_16_0 3_gb_canal_bridges/04_16_03-gb_canal_br-34.jpg Gusset plate pin Joint Connections Welded connection http://www.tatasteelconstruction.com/en/reference/teaching- resources/architectural-teaching-resource/elements/connections/connections- in-trusses 11 http://civildigital.com/wp-con ...

1. HW 2
(1) Visit Monsanto (http://www.monsanto.com) again and
Google to find various information about internal factors of
Monsanto.
(2) Based on the information, perform your own internal audit
for Monsanto. You do not need to perform financial analysis for
this assignment. If you perform the internal audit, you will find
strengths and weaknesses of Monsanto.
(3) List the strengths and weaknesses of Mondanto. Then,
explain why you think so.
Note: Strengths and Weakness are SW of SWOT analysis. We
will use strengths and weaknesses in the last module later.
1
Class Today
• Print notes and examples
• Trusses
– Definition
– Working with Trusses
– Truss Analysis
• Example Problems
• Group Work Time

2. http://www.mst.edu/~ide50-3/printable_notes/13_Trusses.pdf
http://www.mst.edu/~ide50-
3/printable_notes/13_Trusses_examples.pdf
…these are cool trusses
Norman Foster
Sainsbury Centre
Santiago Calatrava
Turning Torso
Shigeru Ban
Japanese Pavilion
KMR
… be inspired!
3
Renzo Piano
Kansai International Airport
Rem Koolhaas
The Shenzhen Stock Exchange
KMR

3. So what are trusses?
http://bridgehunter.com/story/1109/
http://www.americanpoleandtimber.com/img/wood-timber-
trusses-park-BIG.jpg
http://www.hndszj.com/eng/uploads/201008101822313.jpg
Trusses are …
• Structures designed to support loads:
− Will transmit loads through the joints of the structure
− Will ultimately transmit loads to the foundation
• Cost effective in design because:
− Weight is minimized (weight of members is typically
light compared to loads carried, so it is often
neglected)
− Strength to weight ratio is maximized
Image copyright 2013, Pearson Education, publishing as
Prentice Hall
Working with Trusses:
Assumptions

4. • All loads are applied / transmitted at joints
• All members are joined by pin connections
• Consist entirely of two-force members
(review section 5.4)
• Can contain zero-force members
Image copyright 2013, Pearson Education, publishing as
Prentice Hall
Zero-force Members
What are zero-force members?
• Structural members that carry no force
Why do we use them?
• Used to provide stability
– During construction
– If (intermittent) loading of the truss changes
• Shortens chord length and increases
buckling capacity of compression members
7

5. Zero-force Members: Case 1
Zero-force Members: Case 2
10
http://www.tatasteelconstruction.com/static_files/Images/Constr
uction/Reference/
architectural%20studio/elements/Structural%20steel%20trusses/
j2.jpg
http://www.tboake.com/SSEF1/rose2.shtml
http://sluggyjunx.com/rr/georgetown_branch/gallery/04_16_0
3_gb_canal_bridges/04_16_03-gb_canal_br-34.jpg
Gusset plate
pin
Joint Connections
Welded
connection
http://www.tatasteelconstruction.com/en/reference/teaching-
resources/architectural-teaching-
resource/elements/connections/connections-

6. in-trusses
11
http://civildigital.com/wp-content/uploads/2013/09/Rocker-
Type-Bearing.jpg
http://www.dot.state.mn.us/historicbridges/bridge-pictures.html
Rocker
support Truss
Supports
Roller supports
Working with Trusses:
So what is the objective of an analysis?
• To determine
the support
reactions.
• To determine
the forces
supported by

7. individual
members of the
truss. 12
13
FBDs of each
pin and each
member.
(exploded view
showing tension
and compression
forces in a truss)
Image copyright 2013, Pearson Education, publishing as
Prentice Hall
FBD of
whole
truss

8. 14
Working with Trusses:
Analyzing Structural Forces in Truss Members
• Truss members will carry either
– axial tension (T) forces or
– axial compression (C) forces
• There are two methods of evaluating
trusses.
– Method of Joints (static equilibrium of a point)
– Method of Sections (static equilibrium of a
rigid body)
15
Truss Analysis: Method of Joints
Evaluate an individual joint or pin connection.
• Treat each joint as a 2D particle in equilibrium
• Can have a maximum of two unknowns
• Can sum forces in x & y direction

9. 16
Truss Analysis: Method of Sections
Evaluate a section including multiple joints.
• Treat as 2D rigid body in equilibrium
• Must cut through structural members to evaluate the force.
• Maximum of three unknowns (to solve everything)
• Can sum forces in x & y direction
• Can sum moments
17
Method of Approach for Truss
Problems
1. Solve for support reactions if needed.
2. Mark all members on the truss that need to be
solved.
3. Pick the joint / section for which you will draw your

10. FBD. Make sure you have the appropriate number
of unknowns.
4. ALWAYS assume unknown forces to be in
TENSION.
5. Be sure to designate answers as (T) or (C)
6. In subsequent FBDs, draw known forces in the
direction they actually act.
18
Trusses
Free Body Diagram Practice
Draw the correct FBD to
solve for the forces in
members CD, CJ and IJ.
19
Trusses: More FBD Practice
Assuming the necessary support
reactions have already been

11. found, draw the correct FBD to
solve for the forces in members
DE, JM and JH.
20
Trusses: More FBD Practice
Assuming the necessary support reactions have already been
found, draw the correct FBD to solve for the forces in members
CD
and DE.
Can trusses have curved
members?
• Two-force members do not have to be
straight…
• The ideal answer is NO, but …
• Yes, if the members are sufficiently stiff
so that moments developed at the

12. connections are negligible.
• Curved members are not as cost-
effective.
21
Structural Analysis6
Engineering Mechanics:
Statics in SI Units, 12e
Copyright © 2010 Pearson Education South Asia Pte Ltd
Copyright © 2010 Pearson Education South Asia Pte Ltd
Chapter Objectives
• Determine the forces in the members of a truss using
the method of joints and the method of sections
• Analyze forces acting on the members of frames and
machines composed of pin-connected members
Copyright © 2010 Pearson Education South Asia Pte Ltd

13. Chapter Outline
1. Simple Trusses
2. The Method of Joints
3. Zero-Force Members
4. The Method of Sections
5. Space Trusses
6. Frames and Machines
Copyright © 2010 Pearson Education South Asia Pte Ltd
6.1 Simple Trusses
• A truss composed of slender members joined together
at their end points
Planar Trusses
• Planar trusses used to support roofs and bridges
• Roof load is transmitted to the truss at joints by means
of a series of purlins
Copyright © 2010 Pearson Education South Asia Pte Ltd

14. 6.1 Simple Trusses
Planar Trusses
• The analysis of the forces developed in the truss
members is 2D
• Similar to roof truss, the bridge truss loading is also
coplanar
Copyright © 2010 Pearson Education South Asia Pte Ltd
6.1 Simple Trusses
Assumptions for Design
1. “All loadings are applied at the joint”
- Weight of the members neglected
2. “The members are joined together by smooth pins”
- Assume connections provided the center lines of the
joining members are concurrent
Copyright © 2010 Pearson Education South Asia Pte Ltd
6.1 Simple Trusses

15. Simple Truss
• Form of a truss must be rigid to prevent collapse
• The simplest form that is rigid or stable is a triangle
Copyright © 2010 Pearson Education South Asia Pte Ltd
6.2 The Method of Joints
• For truss, we need to know the force in each members
• Forces in the members are internal forces
• For external force members, equations of equilibrium
can be applied
• Force system acting at each joint is coplanar and
concurrent
• ∑Fx = 0 and ∑Fy = 0 must be satisfied for equilibrium
Copyright © 2010 Pearson Education South Asia Pte Ltd
6.2 The Method of Joints
Procedure for Analysis
• Draw the FBD with at least 1 known and 2 unknown

16. forces
• Find the external reactions at the truss support
• Determine the correct sense of the member
• Orient the x and y axes
• Apply ∑Fx = 0 and ∑Fy = 0
• Use known force to analyze the unknown forces
Copyright © 2010 Pearson Education South Asia Pte Ltd
Example 6.1
Determine the force in each member of the truss and
indicate whether the members are in tension or
compression.
Copyright © 2010 Pearson Education South Asia Pte Ltd
Solution

17. • 2 unknown member forces at joint B
• 1 unknown reaction force at joint C
• 2 unknown member forces and 2 unknown reaction
forces at point A
For Joint B,
)(500045cos
;0
)(1.707045sin500
;0
TNFFNF
F
CNFNFN
F

18. BABABC
y
BCBC
x
Copyright © 2010 Pearson Education South Asia Pte Ltd