Megacities are especially vulnerable to earthquakes.
For example, the 10 million residents of Los Angeles County rely on a complex tapestry of water and gas pipelines and electricity and communication cables, and 22,000 miles of public roads. Damage to any part of that infrastructure can impair the rest.
Scientists and engineers study the resilience of the materials, structures, and systems that make up cities, and what they learn informs policy.
Caltech's Domniki Asimaki, a professor of mechanical and civil engineering, develops physics-based computer models to assess how geotechnical structures, such as slopes, embankments, retaining walls, and tunnels, will respond when the ground shakes, deforms, acts like a liquid, or slides because of earthquakes or other hazards.
In this video, Asimaki describes how an earthquake could affect a major city and why modeling future earthquake effects can minimize the risk of a natural hazard turning into a disaster.