Moment-resisting frame

Definition

A moment-resisting frame is a structural system that provides resistance to lateral forces through rigid connections between beams and columns, allowing the building to withstand bending moments during events such as earthquakes. This system is crucial for ensuring the stability and integrity of structures in seismic-prone areas, as it helps them maintain their shape and prevent collapse under stress.

5 Must Know Facts For Your Next Test

1. Moment-resisting frames are designed to provide strength and flexibility, allowing buildings to sway without suffering major damage during an earthquake.
2. The connections in a moment-resisting frame are typically welded or bolted, which helps to distribute loads and moments throughout the structure.
3. This type of frame can be made from various materials, including steel and reinforced concrete, each offering different advantages in terms of performance and cost.
4. To enhance performance, moment-resisting frames can be combined with other systems, like shear walls or braced frames, providing additional resistance to lateral forces.
5. Seismic design codes specify criteria for moment-resisting frames to ensure they can adequately perform during seismic events, helping to protect both life and property.

Review Questions

• How do moment-resisting frames function to provide stability during seismic events?
  • Moment-resisting frames function by utilizing rigid connections between beams and columns to transfer forces and moments throughout the structure. This rigidity allows the frame to effectively resist lateral loads caused by earthquakes, enabling the building to sway while maintaining its overall integrity. The design aims to prevent structural failure by ensuring that the frame can absorb and dissipate energy during seismic activity.
• Discuss the advantages of using moment-resisting frames compared to other lateral force-resisting systems in earthquake-prone regions.
  • Moment-resisting frames offer several advantages over other lateral force-resisting systems, such as their ability to maintain architectural flexibility without sacrificing structural integrity. Unlike shear walls, which can limit openings and design options, moment-resisting frames allow for more open floor plans. Additionally, they can efficiently distribute forces throughout the structure, minimizing localized stresses. These benefits make moment-resisting frames a popular choice in the design of buildings located in earthquake-prone areas.
• Evaluate the role of moment-resisting frames in modern seismic design practices and how they contribute to performance objectives.
  • Moment-resisting frames play a critical role in modern seismic design practices by aligning with performance objectives aimed at enhancing safety and resilience. They are designed not only to withstand significant lateral loads but also to ensure that buildings remain operational after an earthquake. By adhering to stringent seismic codes and incorporating advanced materials and technologies, engineers optimize moment-resisting frames for ductility and energy dissipation. This contributes to minimizing damage and protecting occupants, thus highlighting their essential function in achieving sustainable building performance in seismic environments.

Related terms

Lateral loads: Forces acting horizontally on a structure, often caused by wind or seismic activity, that require special consideration in design.

Shear wall: A vertical structural element that resists lateral forces through shear, typically made of reinforced concrete or masonry.

Ductility:

The ability of a material or structure to undergo significant plastic deformation before failure, which is essential for absorbing energy during seismic events.