Architects recognize two types of loads : dead loads, which consist of the weight of the structure, including the walls, floors, roof, etc ., and live loads, which consist of appliances, furniture and people.
32.
These systems require good drainage systems, movable insulation, and an enhanced structural system to support a 35 to 70 lb / ft 2 ( 1.7 to 3.3 kN / m 2 ) dead load.
33.
In order to accurately design an OWSJ, engineers consider the joist span between bearing points, joist spacing, slope, live loads, dead loads, collateral loads, seismic loads, wind uplift, deflection criteria and maximum joist depth allowed.
34.
Reports suggest that the amount of steel required can be reduced by up to 35 %, due in part to a dead load reduction of as much as 30 lbs per square foot on the overall structure.
35.
The span tables get more complicated because they involve not only live and dead loads and the size of the joist or rafter but also how far apart they are set and what kind of wood is used.
36.
Between 1955 and 1959 the timber deck of the rail level was replaced by steel, and ballasted track was substituted for the earlier waybeam track structure, adding 150 tons of dead load to each span of the bridge.
37.
The designer, Hugh L . Cooper from New York, designed the bridge to hold a dead load of 4800 pounds per linear foot, which he claimed was a weight far greater than any standard freight train at the time.
38.
These forces refer to the dead loads of the construction materials themselves, the live loads of the people and things that may be brought into the building, and the wind loads that occur at the exterior of the building.
39.
The principal ones can be classified as live loads ( loads which are not always present in the structure ), dead loads ( loads which are permanent and immovable excepting redesign or renovation ) and wind load, as described below.
40.
In order to accurately design a pre-engineered building, engineers consider the clear span between bearing points, bay spacing, roof slope, live loads, dead loads, collateral loads, wind uplift, deflection criteria, internal crane system and maximum practical size and weight of fabricated members.
