When I was a kid, I discovered a Calvin and Hobbes comic strip that posed one of my own burning questions: How do they know the load limit on bridges? Calvin’s dad (incorrectly) tells him, “They drive bigger and bigger trucks over it until it breaks. Then they weigh the last truck and rebuild the bridge.” Several decades later, I’m a geotechnical engineer. That means that I work on any construction projects that involve soil. Now I know the real answers to things people wonder about infrastructure. Oftentimes, like Calvin’s dad, they’re thinking about things from the wrong direction. Engineers…