School of PE Blog

Diaphragm forces make up a huge part of the exam (at least in my experience). When I was preparing for the exam, I remember a coworker telling me to be sure I was comfortable with all diaphragm calcs, and I have to say I really appreciated getting that advice!

Diaphragm force calculations can come in many forms - the actual force calculations for both one-story and multi-story buildings, as well as chord and collector calculations. From a definition standpoint, be sure you know the differences between flexible and rigid diaphragms and the calculations that go along with that.

Deflection is a big one, as it ties so many pieces together. There are a few key words you'll need to look out for on this topic.

First, drift vs. deflection. Reread the problem and make sure you're answering the right one!

Secondly, elastic vs. inelastic story drift. This can make a huge difference to your answer, so again, make sure you're reading the problems closely.

Beyond those basic definitions, be prepared for questions on the P-Δ effect, the stability coefficient, and separation (on the same property vs. two separate properties!)

Deflection problems may seem basic at first glance - and you're right, the calculations are basic- but it sure is easy to misread the problem when you're in a rush and accidentally answer the wrong question.

"Story Shear" is one way of saying, make sure you're comfortable with the vertical distribution of forces method and the Equivalent Lateral Force Procedure. This is definitely one of the most quintessential Seismic P.E. question styles, so practice these! Once you get the hang of it, these are easy problems to get right during the exam.

Seismic load combinations are one of those things that will trip you up if you've only been working with gravity load combinations in the past. There are a lot of small rules such as only count snow load if the flat roof snow load exceeds 30 psf, regardless of the slope of the roof, and then only include 20% of the snow load. There are rules for live load, partitions, and equipment loading too, and it's important to make sure you're comfortable with them. These can be easy points to get on the exam if you're prepared!

While the exam may not come out right and ask what seismic design category a given building should be classified as, I am certain that the calculations that lead to this conclusion will be instrumental throughout the exam. These are a basic test of your knowledge of the importance factors, tables in ASCE 7-16 Section 11.4, and site class definitions. There are lots of factors here that need to be multiplied together in various ways. These values would be a great addition to a cheat sheet!

I hope these can help you focus your study efforts, or to act as a final checklist in your week-before-the-exam-self check-in. If you're comfortable and confident with each of these problem types, I think you'll do well on the exam.