6.3.1. LRFD

Try these first

1. 1.

   What does LRFD stand for?

   Hint

   Think about the terms involved in structural safety.

2. 2.

   Why do we apply load factors?

   Hint

   What happens if we don't apply extra safety measures?

3. 3.

   What does LRFD stand for?

   • Load Ratio Factor Design
   • Load and Resistance Factor Design
   • Load Resistance Factor Method

   Hint

   Remember the key phrase involving load and resistance.

4. 4.

   Is the following statement true? 'The factored load is always less than the actual service load.'

   • True
   • False

   Hint

   What does the load factor do?

5. 5.

   A structural member has a theoretical strength of 12000 lbs with a resistance factor of 0.85. If the total service load on this member is 9000 lbs, will it safely support the load based on LRFD?

   Hint

   Calculate factored strength and verify it against the load.

6. 6.

   Design a beam using LRFD principles that requires supporting a factored load of 15000 lbs. If the member's resistance factor is 0.75, what must be the minimum theoretical strength to ensure safety?

   Hint

   What formula do you apply to determine required strength for design?