5.11.2. Fundamental Period Estimation

Try these first

1. 1.

   What is the formula for calculating the natural period (T)?

   Hint

   Think about how mass and stiffness are related to vibration.

2. 2.

   Define effective mass.

   Hint

   Consider which mass affects the overall motion.

3. 3.

   What is the formula to calculate the natural period (T) of an SDOF system?

   • T = 2π√(m/k)
   • T = m/k
   • T = k/m

   Hint

   Remember how mass and stiffness interact.

4. 4.

   True or False: Effective stiffness is not essential for determining the natural period of a structure.

   • True
   • False

   Hint

   Think about what stiffness impacts in a structure's movement.

5. 5.

   Given a bridge with a mass of 8000 kg and stiffness of 25000 N/m, calculate the natural period and discuss its implications for seismic design.

   Hint

   Use the natural period formula and consider its effects on design.

6. 6.

   A building is designed with varying effective stiffness across its floors due to architectural features. Describe how an engineer would approach estimating the natural period.

   Hint

   Consider how multi-directional features might complicate calculations.