Floor Load Transmission To Beams And Girders

Joists supported directly by walls 3 double layer framing.

Floor load transmission to beams and girders. Live and dead loads are given in the building code. Cross sectional areas of the floor beams and girders are 14 7 in2 and 52 3 in2 respectively as shown on the next page figure. This property of floor help in the effective transmission of loads to the various vertical frame elements i e the shear walls columns and walls figure 1. W q t w.

For example a basic floor joist is a beam which is lightly loaded and a roof joist commonly goes by a rafter is also a beam. Top of joists and beams line up may require additional depth for mechanical ducts 6 layered framing. 2 single layer framing. The decking transfers the loads to the joists.

Notice that the other girder on grid 1 has the same load intensity. You should be able to say way that is so at this point. Beams and girders are heavier structural members and are harder to tell apart. Generally a girder is heavier than a beam meaning that if either spans a wider gap or carries a heavier load or supports beams.

Jirsa research report 1746 3 research project 0 1746 effects of overloads on existing structures conducted for the texas department of transportation in cooperation with the. A beam that supports other smaller beams is commonly called a girder while it is still a beam its load bearing capacity is much greater than a beam and is designed to support major portions of a structure. Lateral load distribution on transverse floor beams in steel plate girder bridges by k. The girders or trusses transfer the loads to columns or bearing walls.

By beam action the load is transferred to the main columns that are supporting the girder from below. Joists supported by beams beams by girders and girders by columns 5 flush framing. The center beam carries half of the floor load the partition load and half of the second floor load. The widest span in the floor joist span table in part 2 of this tutorial module showed that floor joists can span 17 2 if they are 2 x 12s spaced 12 o c.

Example load distribution problem 7 the floor system of a library consists of a 6 in thick rein forced concrete slab resting on four floor steel beams which in turn are supported by two steel girders. Area tributary to girder 1 ab. B first floor girder conditions. The joists transfer the loads to the beams.

The weight of the partition is listed in the architectural graphic standards as 10 pounds per square foot. Let s expand our house beyond that 17 2 span capability to 24 feet wide. In buildings that have joists beams and girders the joists carry the direct floor loads transferring these loads to the beams which. The load diagram for the beam would be that of a simply supported uniformly loaded beam having a load intensity.

The load from the above columns are transferred to the girder. So the house dimensions will now be 24 x 13. Joists supported by beams and beams by columns 4 triple layer framing.