The ones that could deal with the most strain resulted in better grades. We stressed the bridges until they snapped. The teacher had divided us into teams and instructed us to come up with bridge designs, and the team with the strongest bridge would win. This flexular modulus definition reminds me of what we did in high school to determine how strong our wooden bridges were. With something as thick and as sturdy as glass, you will either hear it break or hear it do nothing at all. I can see how glass would yield to stress suddenly instead of deforming. The glass will break long before the rubber will. So, though rubber would bend much further because it is more elastic, it is actually stronger than the glass when tension is being measured. This is because elastic modulus measures stress changes when strain is applied. September 18, – It sounds strange, but glass would have a larger elastic modulus than rubber. In a structural perspective, could anyone out there help educate me as to what these test results really mean? Explain the concepts of stress and strain in describing elastic deformations of materials Describe the types of elastic deformation of objects and materials. My problem is that some materials passed the flexural stress but failed to meet the Flexural Modulus requirement, and for other samples its the other way around. at 5 percent strain, and for a Flexural Modulus of at least 300,000 psi. For example, the contract specs for mechanical testing call for a flexural stress of at least 4,000 psi. Young’s modulus of rocks varies fromabout 10 to 100 GPa, and Poisson’s ratio varies between 0.1 and0.4.Theelastic properties of the earth’s mantle and core can be obtained from seis-mic velocities and the density distribution. In flexural stress, however, both elastic and plastic behavior can occur, depending on the magnitude of the bending moment and the properties of the material. I am a construction inspector and I have a problem interpreting the test results submitted to us. I am only giving my 2 cents for our mutual edification. Please consult someone else who is qualified if you are going to do job related stuff. What I post is in no way professional advice and I am not giving it as such. However, it just isn't strong enough to handle the flexural stress desired.ĭisclaimer: I'm only a third year undergrad. The other case is that the material has the right slope (flexural modulus), meaning it is stiff enough. In other words, it is too bendable, even if it doesn't break. What you're describing is that some materials don't have a high enough slope (flexural modulus) although they do reach the flexural stress desired (I am assuming it is yield flexural stress). November 29, It is easier to understand if you look at the stress strain graphs. Anumeya: flexural stress is highest stress within material at its moment of rupture while as flexural modulus is the ratio of stress to strain in flexural defomation.
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