Light Truck Frame Joint Stiffness Study Phase 1 Final Report

JOINT STIFFNESS TOOLBOX
Notes:
* Modify the input values (yellow) based on
your design criteria. There are two columns in
which in to input and evaluate data, case 1
and case 2. The calculated stiffness will be
displayed in red.
* Design variables are listed in order of
influence on stiffness.
Illustration Key:
A = Outer Rail
B = Inner Rail
C = Crossmember
Design Rules:
* These are the major contributors to
the joint stiffness:
- Crossmember thickness
- Inner side rail thickness
- Crossmember height
- Crossmember width
* The weld flange should be as small
as possible.
* Design variables are listed in order of
influence on stiffness.
* Click on the animation to the left of the
variables and loading conditions to see an
animation of respective shape variable or
loading condition.
* The mass calculation is based on 150 mm
extension of joint members from the side rail
to interface. This is to serve as a reference,
not the absolute value.
* The password to unprotect cells in this
spreadsheet is: steel.
Joint Observations:
Fore/Aft Loadcase (Mz)
* Lots of flange deflection in the crossmember
and siderail.
* Side rail wall also has a lot of deflection.
Vertical Loadcase (Mx)
* Crossmember flange deflects quite a bit,
especially at the top.
* Side rail wall deflects a lot.
* Side rail wall also has a lot of deflection.
Torsional Loadcase (My)
* Weak in torsion because the crossmember
is an open section.
* There is a lot of flange deflection.
* The top flanges do not attach to anythingattaching
to the side rail would increase the
stiffness.
Figure 41: Joint 5 Joint Stiffness Toolbox Spreadsheet
Joint Observations, Notes and Design Rules
Report: A/SP-005-1 Light Truck Frame Joint Stiffness Study 68