GEOLOGY

Detailed explanation-1: -Mid-rise buildings-especially ones with unreinforced masonry are often the most dangerous places to be. Their rigid walls tend to crack and crumble rather than sway.

Detailed explanation-2: -Japanese high-rise construction commonly uses a grid of steel beams and columns that evenly distributes seismic forces across the structure and diagonal dampers that serve as shock absorbers. American high-rises are typically built with a concrete core that resists most of the seismic forces of an earthquake.

Detailed explanation-3: -A lack of bond beams, poor connections among the walls and the roofs, and large unsupported wall lengths cause the separation of walls and cause damage to occur via the of out-of-plane mechanism. Thus, the whole or the significant parts of the wall fall down during the earthquake.

Detailed explanation-4: -The epicenter is on the earth’s surface directly above the focus where seismic waves originate. The damage caused by an earthquake is more severe when an area is closer to the epicenter of the earthquake as the intensity will be greatest/vibration strongest.