deadload

Dead load, in structural engineering, is the permanent, static weight that a structure must support due to the structure itself and fixed components. It does not include live loads, such as occupants or movable furniture, nor environmental loads like wind or snow. Dead loads are the constant part of the load that remains present during the life of the building.

Dead loads encompass the weight of the structural framework (beams, columns, slabs), walls, roofs, floors, finishes, and fixed equipment. They also include built-in fixtures, insulation, and other permanently attached systems and elements. Changes in dead load can occur with renovations, deterioration, or moisture-related changes.

Calculation and representation: Dead load is treated as a constant during design. Engineers estimate it by summing the weights of all permanent components and express the result per area or per length, using units such as kN/m, kN, or pounds per square foot (psf). This value is combined with live-load estimates to assess overall design demands.

Role in design and codes: Dead load influences foundation design, framing, connections, and overall structural behavior, including deflection and stress distribution. Design codes and standards, such as the International Building Code (IBC), ASCE 7, and Eurocodes, specify procedures for determining dead loads and for applying load combinations to ensure safety and performance.

Limitations and changes: Dead load can change over time due to remodeling, retrofits, material aging, or moisture absorption. Any significant modification to a structure often requires re-evaluation of dead-load effects to maintain safety and code compliance.