24.1.4. Behavior of Reinforced Concrete Section Under Load

Try these first

1. 1.

   What is equilibrium in the context of reinforced concrete?

   Hint

   Think about how forces interact in a beam.

2. 2.

   What is the typical failure strain for normal strength concrete?

   Hint

   Consider the proportionality in stress-strain.

3. 3.

   What is the primary purpose of analyzing equilibrium in reinforced concrete design?

   • To calculate cost
   • To ensure structural integrity
   • To determine aesthetics

   Hint

   Think about the safety aspects of construction.

4. 4.

   True or False: The failure strain of concrete varies with its compressive strength.

   • True
   • False

   Hint

   Consider if stronger concrete fails at a different point.

5. 5.

   A 10-foot-long reinforced concrete beam has a cross-section that is 10 inches wide and 12 inches tall. If the steel reinforcement’s tension equals 30 kips at mid-span, what is the equivalent compression in the concrete at the same section?

   Hint

   Apply equilibrium principles to balance the concrete and steel.

6. 6.

   Given that the failure strain for a concrete beam is 0.003, if the strain observed during loading is 0.0025, will the beam fail?

   Hint

   Compare the observed strain with the failure strain.