The strength of an earthquake is scaled 1-10. Scientist use magnitude or Richter scale to measure earthquakes. The scale goes from 1-10. 1 is the lowest causing damage and 10 being the most causing damaged. This means that the higher the number is the more damage it will cause.
The stronger the building structure is the better it will stay up during an earthquake. If there are two buildings and building number one is a tall and weak number two