Joints Attachments
If the beam was cut into sections it would basically be put back together with joint attachments and screws and bolts. It would restrict the beam from rotating or pivoting in an unnatural manner and it would be easy to assemble and disassemble. The image below is a rough interpretation of the idea put foward.
Pinned Joints
Probably the simplest idea that was produced. The beam could be split into sections and a male/female connection be cut into each section. Then each joint could be held together by a simple bolt and nut. This idea would be the quickest and most efficient way of splitting the beam. The idea does have flaws, one being that the restraints on the joint do not prevent the pieces from pivoting.
These ideas however all have one thing in common and that is that they will drastically increase the beams chances of failing. This is due to a phenomenon known as Stress Concentration.
Stick Welding
This is the strongest idea produced. If the beam was to transported to the event and when it is to be used, each part is welded together. When the beam is needed somewhere else the beam does not need to be separated again so it can be carried as a whole piece. This does however mean that a stick welding kit would be needed when the crane is being used and someone qualified would have to construct it, but stick welding is one of the quickest and simplest welding procedures it should not take too long to assemble.
All these ideas however have one thing in common, they would all increase the chances of failure massively. This is because of a phenomenon known as Stress concentration.
Stress Concentration
Definition: (mechanics) A condition in which a stress distribution has high localized stresses; usually induced by an abrupt change in the shape of a member; in the vicinity of notches, holes, changes in diameter of a shaft, and so forth, maximum stress is several times greater than where there is no geometrical discontinuity.
If the beam was to be put into sections discontinuities in the geometry would have to be created and as stated would greatly increase the force applied to that point.
The Stress Concentration is measured as the Stress Concentration factor which is either calculated through theoretical methods or by using finite element methods. It calculates the stress along the axis of the discontinuity with stress applied on that point. The factor is a function of the geometry of the discontinuity and not the size, which means it does not matter how big it is, but of what shape it is.
Winch Impairment
Another issue that will arise is the track on which the winch will run will be distorted. This will either restrict or slow down the functioning of the crane, which in turn causes the crane to be unsafe and unreliable.
An example is a simple hole through a sample cause the force lines to distort in the manner shown below.
So in conclusion it would not be plausible to make the beam in sections to be put together otherwise it would undermine the quality of the crane, the safety of the people working with it and general sales of the product. The beams strength is dependant on it being one complete object
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