十万个为什么·科学启蒙30篇（2）
13 / 30
正在校验访问权限...
Why Do Bridges Not Collapse Under Heavy Traffic?
为什么桥梁不会在重载车流下坍塌？
-
Engineers carefully calculate how much weight a bridge can safely hold.
-
They use strong materials like steel and reinforced concrete to handle heavy loads.
-
The shape of the bridge—such as arches or suspension cables—helps spread force evenly.
-
Wind, temperature changes, and even earthquakes are tested in computer models before building.
-
Regular inspections check for tiny cracks or rust that could grow over time.
-
Expansion joints allow bridges to safely shrink or stretch with temperature shifts.
-
Each part of the structure shares the load so no single point bears too much stress.
-
Modern sensors now monitor vibrations and strain in real time during rush hour.
-
Even a small design error could cause failure, so safety margins are always built in.
-
That’s why well-designed bridges can last over a hundred years without collapsing.