4. Computation of Design Forces in Members

Try these first

1. 1.

   Define dead load.

   Hint

   Think about what contributes weight when a building is built.

2. 2.

   What do live loads include?

   Hint

   Consider things that can change over time.

3. 3.

   Which of the following is a dead load?

   • Live load from people
   • Weight of the structure itself
   • Wind pressure

   Hint

   Remember that dead loads are constant.

4. 4.

   True or False: Wind loads can only cause downward forces on structures.

   • True
   • False

   Hint

   Consider how wind interacts with buildings.

5. 5.

   Given a truss with a top chord designed to withstand a maximum dead load of 4 kN and a wind uplift of 2 kN, calculate the total axial force the truss top chord must support.

   Hint

   Don’t forget to add the effects of both loading conditions.

6. 6.

   If a certain truss member experiences both a downward dead load of 3 kN and an upward wind load of 1 kN, what are the axial forces acting on that member?

   Hint

   Consider the direction each force acts.