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In one case study questions from the practice exam, it asks about calculating the occupancy load based on the area without providing the table 1004.1.2. So my question is that do I need to memorize the contents in this table or does this information would be provided at the exam?

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Great question @hanpingsh !
@coachlizschneider do you mind answering this?

Thanks for the question @hanpingsh!
Generally speaking, NCARB is moving away from memorization of data for the 5.0 version of the exams. In most cases, especially a case study question, I would expect the relevant code section to be provided to you. That being said being familiar with certain sections of the code may help you to more quickly answer the question, saving you valuable time.

In one of the practice exam, it asks for the height of a retaining wall:

A structural engineer has told the architect that the total pressure on the retaining wall, that was designed, cannot exceed 1500 plf. The concrete wall has a total length of 40 feet and is adjacent to a parking lot.

How high can the architect make the wall? Assume the pressure is 30lbs/ft^3

The answer is derived from the following formula:
P = ½ (30 lbf / ft^3) h^2
1500 plf = ½ (30 lbf / ft^3) (x ft)^2
x = 10 ft.
Can you explain the logic or perhaps pointing out a specific direction where I can study myself?

@hanpingsh This question uses Rankine’s Active Earth Pressure formula to find the height of the wall. The formula says the P (total pressure on the wall) is equal to 1/2 x K(the weight of the soil) x H^2 (the height of the retaining wall squared). In this case H is the unknown factor. P=1500plf; and K=30lbs/ft^3 If you rearrange the formula to solve for H; you have H= the square root of (2xP/k) or the square root of (2x 1500/30) =3000/30= 100; and the square root of 100 is 10. So your retaining wall can be 10ft high.


I have a few questions, based on the IBC code you and put an exterior door off the classroom and not have to sprinkler the building. What if the Owner does not want an exterior door then what should you do?

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Hi @ashfordR1 & welcome to the Community!
That’s a good question, let’s see if one of our expert architects can help. @coachlizschneider do you mind jumping in?

@ashfordR1 I’m not sure I fully understand your question. Are you saying that by placing an exterior door off of the classroom you are able to avoid sprinklering the building per IBC, but the owner does not want to add the exterior door or sprinkler the building?
If so, section 903.2.3 Group states that sprinklers are only required at area larger than 12,000 sqft for group E occupies or if a portion of the building is below the level of exit discharge. So your client could keep the area under 12,00sqft or avoid placing any portion of the building below the level of exit discharge.

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