Primary structural archetypes for tall buildings
Beam-column frames (moment frames) use rigid connections to transfer loads. Columns and beams form a grid where joints resist bending, allowing lateral sway to be absorbed by frame deformation. Shear walls are solid vertical elements (typically reinforced concrete or masonry) that resist lateral loads with minimal deformation. Tube systems wrap the building perimeter with closely spaced columns and walls, creating a very stiff lateral system that can efficiently support 100+ story heights. Diagrid systems (diagonal grids) use diagonal bracing to create stiffness while minimizing columns, often favored for slender or curved towers. Braced frames use diagonal X or chevron patterns to resist lateral loads independently of vertical load-carrying columns.
Selection by height, cost, and design intent
Low-rise buildings (under 10 stories) typically use simple moment frames or wood-stud walls. Mid-rise (10-40 stories) combines moment frames with shear walls for redundancy and cost efficiency. High-rise (40-100+ stories) often uses tube or diagrid systems because their lateral stiffness scales better than simple frames. Moment frames allow more open floor plans (fewer internal walls) but require deep beams and rigid connections, increasing cost. Shear wall systems maximize usable floor area but restrict window placement and plan flexibility. The choice balances structural efficiency, architectural flexibility, construction speed, and material availability. Seismic and wind engineering often drive system selection: a tube building performs excellently in wind, while braced frames with ductile connections excel in seismic zones.