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## Main Question or Discussion Point

Hi, great forum

My apologies for my first post being a question, but I am trying to calculate the size of a Steel Universal I-Beam that I will need to replace an old wooden beam.

It is a simply supported beam that needs to hold up a uniformly distributed load of around 1.5tonnes, over a length of 14.5ft. The beam is supported at either end by an upright column.

I have calculated this weight using the following:

Surface Area of Slate & Wood Roof = 103 sq ft @ 16lbs / sq ft

= 1624 lbs

Surface area of Wood Panal and Partially Glazed wall = 100sq ft @ 6lbs / sq ft =609lbs

TOTAL Weight = 2233 lbs

Safety Factor = 2233*1.5

= 3349lbs

(I also included an assumed live load of approximately 40lb sq ft, but did not show this in teh calculatiosn above.)

I have tried using BM = wl^2/8 and D= 5/384 x wl^3/EI , but I am not having much luck as I am getting figures that say a 203 x133 will be sufficient but this seems light.

Any help would be greatly appreciated. If you could show me the calculations it would be fantastic so I can see where I am going wrong.

Rob

My apologies for my first post being a question, but I am trying to calculate the size of a Steel Universal I-Beam that I will need to replace an old wooden beam.

It is a simply supported beam that needs to hold up a uniformly distributed load of around 1.5tonnes, over a length of 14.5ft. The beam is supported at either end by an upright column.

I have calculated this weight using the following:

Surface Area of Slate & Wood Roof = 103 sq ft @ 16lbs / sq ft

= 1624 lbs

Surface area of Wood Panal and Partially Glazed wall = 100sq ft @ 6lbs / sq ft =609lbs

TOTAL Weight = 2233 lbs

Safety Factor = 2233*1.5

= 3349lbs

(I also included an assumed live load of approximately 40lb sq ft, but did not show this in teh calculatiosn above.)

I have tried using BM = wl^2/8 and D= 5/384 x wl^3/EI , but I am not having much luck as I am getting figures that say a 203 x133 will be sufficient but this seems light.

Any help would be greatly appreciated. If you could show me the calculations it would be fantastic so I can see where I am going wrong.

Rob

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