Granite ?

Question

If i had a beam made of granite that was 6 foot tall and 1 foot wide and spanned a 25 foot gap how much wieght would it be able to hold safely?

Answer 1

As your last poster said, there's not enough info., and building a down-sized model for testing won't even give reliable results because granite is an "aggregate" of compressed metamorphic rock: It therefore has inherent "fracture points" that will vary with each slab... it would be better to use a steal I-beam and then "dress it" with your "rough cut" or polished granite with industrial adhesive. Granite is great for supported floors, walls, etc. but is not, to my understanding, a desirable choice for supporting weight over a span of 25 ft.!

Answer 2

The structural integrity of all rocks is so variable that it is impossible to answer this question. That is why engineers don't use building stone to provide structural strength in clear span design - except of course in third world countries where earthquakes cause these structures/buildings to collapse rather predictably.

In any event, a piece of granite with those dimensions would weigh about 11.5 metric tonnes (1.83 x 0.305 x 7.62 m x 2.7 SG). I'd say thats testing the limits of its internal strength and you wouldn't catch me sleeping under it. Of course if you took that same piece of granite and cut it into bricks and made an archway, then it would be extremely strong.

Answer 3

Depends on the thickness of the granite. 6 feet by 1 foot doesn't provide enough information for span distance strength. Good luck

Answer 4

If it were a single piece of granite that were mined in one piece, it would not be homogeneous and the grain would most likely play a major factor in the strength of the material.