Failure Types

Soft-Story Collapse

Occurs when the ground floor is significantly weaker than upper floors, often due to large openings (garages, storefronts) or fewer walls. During earthquake shaking, the weak story concentrates deformation and eventually collapses.

📊 Ground Motion Characteristics

Typical Conditions:
• Strong lateral forces
• Medium to long duration shaking
• Inter-story drift concentration

🔧 Reinforcement Solutions

Recommended Retrofits:
• Add shear walls to weak story
• Install moment-resisting frames
• Strengthen existing columns
• Add steel bracing systems