Structural Rigidity, Anybody used structural foam? Options

[Beebo Kanelle]

Has anybody here used structural foam on their 914 to increase structural rigidity?

Here is the original Abstract of that SAE paper 1999-01-1785

"Stability and structural integrity are extremely important in the design of a vehicle. Structural foams, when used to fill body cavities and joints, can greatly improve the stiffness of the vehicle, and provide additional acoustical and structural benefits.This study involves modal testing and finite element analysis on a Sport utility vehicle to understand the effect of structural foam on modal behavior. The modal analysis studies are performed on this vehicle to investigate the dynamic characteristics, joint stiffness and overall body behavior. A design of experiments (DOE) study was performed to understand how the foam's density and placement in the body influences vehicle stiffness. Prior to the design of experiments, a design sensitivity analysis (DSA) was done to identify the sensitive joints in the body structure and to minimize the number of design variables in the DOE Study."

And the Conclusion:

"The most sensitive area of the body were found to be the A-pillar, the D-pillar and their joints. With structural foam injected into this sensitive areas, the vehicle body was significantly stiffened, as shown by the increase in modal frequencies. The 1st torsional mode was most effected with an increase of 29.1% in modal frequency.The design sensitivity analysis and design of experiments described here, can be used to identify the sensitive ares of the body structure. This results are useful in the determining the best application locations for structural foam."