Light Truck Frame Joint Stiffness Study Phase 1 Final Report

JOINT STIFFNESS TOOLBOX
Notes:
* Modify the input values (yellow) based on
your design criteria. The calculated stiffness
will be displayed in red.
* Design variables are listed in order of
influence on stiffness.
Illustration Key:
A = Side Rail End Square
B = Side Rail Plate
C = Crossmember
D = Side Rail C Channel
Design Rules:
* Increase crossmember thickness to
increase stiffness in all three directions.
* Increase crossmember thickness to
increase stiffness in all three directions.
* Increasing the side rail height
increases the stiffness in the Bending
(Kx) and Torsional (Ky) loading
directions, but decreases the stiffness
in the Fore/Aft (Kz) direction.
* All of the other design variables have
a small, but significant impact on the
joint 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 compliance is a combination of
deflections in the crossmember, bottom
reinforcement, and side rail after wall. The
max stress occurs at the top and bottom
corners of the crossmember.
* Vertical compliance is a combination of side
rail, crossmember and bottom plate deflection.
* Torsion compliance is mostly in the
crossmember and is probably higher because
of the hole in the crossmember. High stress
occurs in the bottom reinforcement plate at
the weld temination and the top of the side
rail.
* Thickness Importance: Crossmember
thickness then outer Side Rail and plate
thickness.
Figure 35: Joint 2 Joint Stiffness Toolbox Spreadsheet
Joint Observations, Notes and Design Rules
Report: A/SP-005-1 Light Truck Frame Joint Stiffness Study 62