How Do You Determine Displacement and Rotation at Point A in a Beam?

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To determine displacement and rotation at point A in a beam with constant EI, it is established that there is no displacement at A, which can be confirmed by substituting x with 0 in the deformation equation u(x). The rotation at point A is defined as the first derivative of u(x), or du(x)/dx, which represents the slope of the beam at that point. This slope can be approximated as the angle of rotation for small angles, where tan θ is approximately equal to θ. Understanding these concepts is crucial for analyzing beam behavior under load. The discussion clarifies the relationship between displacement, rotation, and slope in beam mechanics.
kasse
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A beam AB has constant EI and u(x) describes the deformation:

http://www.badongo.com/pic/625051

The first task here is to show that there's no displacement or rotation at A. For the case of the displacement, I guess I can do that simply by replacing x with 0 in the u(x)-equation?

But how about the rotation? What is meant by that? Is it the same as slope?
 
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kasse said:
A beam AB has constant EI and u(x) describes the deformation:

http://www.badongo.com/pic/625051

The first task here is to show that there's no displacement or rotation at A. For the case of the displacement, I guess I can do that simply by replacing x with 0 in the u(x)-equation?

But how about the rotation? What is meant by that? Is it the same as slope?


Yes and yes the first derivative du(x)/dx is the rotation or slope (Remember that for small angles \tan \theta \approx \theta)
 
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