Dynamic loads come from things like wind, earthquakes, and vibrations. These forces can really change how buildings and other structures act. Different materials behave differently when faced with these loads, which is important for design and safety. Let's break it down:

1. Elasticity vs. Plasticity

• Elastic Materials: These are materials like steel and rubber. They can stretch or change shape when something heavy is on them, but they go back to their original shape when the weight is lifted. This is really important for buildings during earthquakes. Steel structures can handle these forces without getting damaged.

• Plastic Materials: On the other hand, materials like concrete and brick are not as flexible. They can crack when faced with heavy loads, so they need extra support, like steel bars, to help them stay strong.

2. Time-Dependent Behavior

• Some materials, like certain types of plastics called polymers, are special. They show something called viscoelasticity. This means they can act both stretchy and sticky. They help absorb vibrations over time, making them great for protecting buildings from sudden movements.

3. Example of Response

• A good example is tall buildings. They often have devices called dampers. These dampers are made from different materials and help reduce swaying caused by wind or earthquakes.

In short, when picking materials for a building, it’s important to think about how they will react to dynamic loads. This helps keep the structures stable and strong.