Momenttirunko

Momenttirunko is a Finnish term that translates to "moment frame" in English. It refers to a structural system designed to resist lateral forces, such as wind and seismic loads, primarily through the flexural rigidity of its members and their connections. Unlike shear wall systems or braced frames, moment frames do not rely on diagonal bracing or stiff vertical walls for lateral stability. Instead, the beams and columns are rigidly connected, forming a stable framework that can resist deformation by bending.

The design of a moment frame involves careful consideration of the forces acting on the structure and the capacity of the beam-to-column connections. These connections are critical as they must be able to transfer bending moments and shear forces between members, ensuring the frame acts as a continuous unit. Moment frames are often used in buildings where open floor plans are desired, as they do not require the internal bracing that would obstruct such layouts. They are commonly found in mid-rise to high-rise structures. The flexibility of moment frames, while allowing for some sway, is engineered to remain within acceptable limits to ensure the safety and serviceability of the building.