Janice Jo Nola
Fairview High School
Algebra II; Geometry 

Dr. Michael Miga - Biomedical Modeling Lab 

The main focus of our lab was compression testing to determine the elastic properties of tissue using Young's modulus (or stiffness). The purpose of this testing is to determine the degree of stiffness of fibrotic tumors. Poisson's ratio and viscosity were measured using the Bose Electro Force 3100 and the Win Test program to determine the changes in soft tissue stiffness.  This stiffness measurement was made by placing the sample between two plates and setting the test to compress every few seconds to determine the elasticity of the sample. Ramps (compression force) and dwells (seconds) were used to determine the linear measure of the samples. By graphing the amount of force per second applied to the samples a negative slope reflecting stiffness was determined for each model.   

This experience will allow me to add another important layer to the bridge project that I do in my geometry classes.  After construction of the brides I will work with the physics teacher, who also participated in this program, to determine the stress load of each bridge using moment of inertia. When the ramps and dwells were connected in my research, a negative linear function was formed to determine how stiff the sample was. I discovered that this slope could also be used in a comparative study when bridges are stress tested using stress to collapse the mass or weight of the bridge.  During the testing phase of the project each bridge is placed on a lift, a chain is placed over the center and weights are placed on a platform attached to the chain. Weights are added until the bridge collapses.

By using the weight of the bridge for the y-axis and the load for the x-axis, we will be able to look at the slopes to determine which bridge actually was the strongest.  Hopefully they will make the connection that the more horizontal the slope the stronger the bridge and the more vertical the slope the weaker the bridge.  This is actually how the elasticity models are calculated.