How do you calculate Universal Distributed Load?

Answer 1

Hi, I am only an undergrad civil engineer so feel free to correct me if I am wrong, but I will try to help! Say we are dealing here with a steel beam, spanning across a ceiling, and the load applied to it is the floor above. Let's presume it is supporting 2 loads, the concrete slab above it (dead load) and the service load (live load), i.e. people walking over the floor and hence varying. We need to estimate the area of floor the beam is supporting, so obviously this will be in m^2, and we also need to depth. We also need the characteristic service load for our type of building, and this can be found in a book such as the Metric Handbook (a must have for engineers!!) We then take the total area value to British Standards tables, which will give us a self weight of the concrete for a certain depth and a certain characteristic service load. It will also tell us the effective span of the floor. We then add together the dead load and live load, for the total load on the beam, so: applied load = (total area x concrete self weight) + (total area x characteristic service load) This should give you quite a large value with real buildings. UDLs are measured in N/m or kN/m, and so finally we just need to divide the total load by the span of the beam in metres. Also, not all of the load will be on the beam, some will be applied to the supporting structures, so you can assume that only somewhere around half of the final load is the UDL over the span of the beam. Hope this helps, Luke