A ___ collapse may occur when a heavy load concentrated near the center of a floor.

A ___ collapse may occur when a heavy load concentrated near the center of a floor.

• A. Pancake collapse
• B. V-shaped collapse
• C. Lean-to collapse
• D. A-frame collapse

Answer: (B)

When a floor fails, the pattern it makes reveals how the load and supports gave way. If a heavy load is concentrated near the center of a floor, the center joists and structural members are overloaded and fail first. As the center drops, the surrounding floor sections lose support and tilt downward away from the center, creating a V-shaped collapse with the apex at the center. The outer edges may remain connected to walls, so the collapse appears as two wings opening outward from the middle. This differs from a pancake collapse, where floors drop straight down in a block-like stack due to uniform failure. It also differs from a lean-to collapse, where one side collapses while the opposite side remains supported, producing a sloped face. And it differs from an A-frame collapse, where a pair of walls or members give way and fold inward to form an A-like profile.

When a floor fails, the pattern it makes reveals how the load and supports gave way. If a heavy load is concentrated near the center of a floor, the center joists and structural members are overloaded and fail first. As the center drops, the surrounding floor sections lose support and tilt downward away from the center, creating a V-shaped collapse with the apex at the center. The outer edges may remain connected to walls, so the collapse appears as two wings opening outward from the middle.

This differs from a pancake collapse, where floors drop straight down in a block-like stack due to uniform failure. It also differs from a lean-to collapse, where one side collapses while the opposite side remains supported, producing a sloped face. And it differs from an A-frame collapse, where a pair of walls or members give way and fold inward to form an A-like profile.