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The weight of the beam is frequently ignored in homework and at the lecture or the class, for simplicity. Unless it is given in the question. And for the second part of your question, I would say first do the test without self-weight and then with that, with a comment explaining the difference, this way it will be more clear. As you already know the weight ...


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Macaulay and UDL If by Macaulay's method you mean the use of singularity function (the use of Macaulay's bracket <>), then the method can account for distributed load. For example the moment for a Uniform distributed load (UDL) starting at point x=a and carrying until the end of the beam is : $$M(x) = \frac{w}{2}\langle x-a\rangle^2$$ Discrepancy in ...


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You need to know what type of lumber is used in your ceiling to know its strength for moment and shear,$F_b \ , V_{allowable}$ and its elastic modulus, E. but for illustration assume a lower range of $$F_b=1000psi \ and\ V=100psi$$ Then your moment is $$M=\omega l^2/8= \omega*(11*12)^2/8=2178\omega$$ you beam elastic module $S_x$ is $$S_x=bh^2/6=2*8.8^2/6=...


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Poisson's ratio is defined in the case of uniaxial tensile testing. As such the x axis is in the direction of the loading, while the y and z axis are transverse. In isotropic materials it doesn't make any difference which axis the material is tested. However for anisotropic (i.e material that don't behave in the same way in all directions), there are ...


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The definitions below ar quite clear: https://www.mechanical.in/what-is-stress-and-types-of-stress/


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Example: You provide confinement reinforcing to a column. That is passive confinement, which will automatically activate and provide confining stress, if there is the need, after a certain amount of strain. But if you applied that confinement force actually yourself, instead of the confining reinforcing, then that would be active confinement. You would be ...


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Modern building failure due to tipping is rare but did occur, usually under strong earthquakes and loss of foundation (soil and structure), as the tilt will shift the gravity center of the building that induce a tremendous amount of stress on the foundation piling and the soil mass surrounding the piling. So, how much is too much for a building to handle (...


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It depends what you think should be the frequency of the external force, which will cause it to vibration. If the frequency of the external force is overlapping with any of the natural frequencies, then the structure resonates and you have high amplitude of vibration, which can catastrophically damage the structure.


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Assuming that the model is adequate and appropriate, then to answer your second question: Which frequency out of those five is right? All of those modes and frequencies are possible in the structure. Usually the frequencies are provided in increasing order (i.e. the numerical smallest is presented first etc). The frequency that is usually more important, ...


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We can use some examples. Direct shear stress: Punching a hole into a sheet of metal with a tool. Shear stress caused by a pair of scissors on the paper when cutting it. shear stress on a footing due to a load of column. Indirect shear stress: the shear caused by a change of moment in a beam. the shear created at the base of the column due to column's ...


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A direct application of applied load/moment are the reason why we experience anything that happens within the structure (like deformations, strains, stresses etc). If not direct load/moment are applied, then nothing will happen and the body will just remain as it is. So anything that happens (for instance, warping in a rectangular shaft due to torsion, which ...


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