Transmitting load to a fixed support of a structure

Question

In structural optimization, we try to design our structure in a way to sustain loads in the best way possible. An example could be thinking about transmitting loads to fixed supports in an optimal way.

I am thinking of the instant when a load reaches a support. First, before the load reaches the support, it has already traveled inside the structure, so I don't know why we care to transmit it to the support. Second, I suppose that the support for the load is considered as its "end life". So, why do we want the load to vanish at the support and not within the structure itself?

Answer 1

Because the force of the load needs to be counteracted (remember Newton's 3rd law?).

A force doesn't just disappear, it needs to be counteracted or things will start moving (remember Netwon's 2nd law?).

A support is a great way to create a force in the opposite direction that will prevent the force from acting on elements that cannot handle that force.