Also how do you relate the output of the scale model to that of the life-size structure?
Tests to be performed when testing model on Shaking table are divided into two groups:
• Tests to determine the dynamic characteristics such as their frequency, shape and vibration damping coefficient
• Tests of seismic response
Several posibilities ... one could be that in order to relate the output of the 'scale model' to that of the 'life-size structure', a 'life-size structure model' consisting of all relevant aspects (such as material properties, etc.) must be accurately modeled, to allow for the scale model & its interactions with the outside world to be reliably related to the 'life-size structure model'.
The key is to understand (or have a clue) about the variables that affects your phenomena. For example, if density matters, somehow you should consider it. It is important to read books throughly dedicated to scaling, for instance "Scaling" by Barenblatt. If the phenomena are already described by equations (like many fluid mechanics do) it is easier.. simply by changing length by following Pi-Buckingham theorem, you'll be able to understand which variables are relevant.
The fundamental question os what are you trying to scale?
If you are not sure of what does affect the response of the "thing", you should perform experiments or simulation varying parameters (Design of Experiment) so as to learn more on what you are studying and start creating the "Dimensionless Numbers" that are relevant for your phenomena.
If you are dealing with mainly elastic seismic response, I believe that is relevant Young Modulus, Density and Length (of course). See that, if you use exactly the same material and scale by beta=1/100 (MLT basis), your resonance frequency will be hundred times higher (1/beta) whilst your displacement 100 times lower (as beta).
Hope that helps....
Sometimes is also interesting to define a basis different from MLT (mass length time) in order to account for differences in material properties, an approach called "Distorted Similarity". It important to define the desired characteristics of your model and so verify the influence on the other parameters.
Thank you Leonardo for your help in this aspect. I will take into consideration the factors you have explained here and will get back to you on the progress of the work.
- Badges
- Science topic
- Similar topics
- Philosophy Of Science
- Models