Masonry on PE Exam

[FlashSet]

I am reviewing the design standards recommended/required for the PE structural exam and the footnote for the masonry code states:

"Examinees will use only the ASD method, except strength design Section 3.3.5 may be used for walls with out-of-plane loads."

Looking through MSJC the strength design chapter includes sections for in-plane and out-of-plane loads on walls (sections 3.3.5 and 3.3.6), but the ASD chapter is more vague (section 2.3.3 Axial compression and flexure).

Does anyone have any insight on what is going on here; why are they allowing strength design for these walls? It seems very nonsensical to study ASD for all masonry members, and then switch to strength design for another.

Thanks in advance.

 

[concretemasonry]

That is because of most slow to revise codes use the design concept because it is based on the testing and documentation conducted for many decades.

The MSJC document referenced is probably a consensus standard (commonly referred to as ACI 530) because ACI carried the burden of publication and it is actually the combination/consensus standard of different design methods and the reasons for the use. It includes the principals, accompanying specifications and most importantly the commentary. The document is the most commonly used source adopted by reference by model codes nationally and internationally.

Individual entities (jurisdictions, sates or countries) can adopt the entire standard or just portions depending on the applicability for local conditions. Some localities adopt only portions or can legally put stricter conditions in place of the "pure" standard. during the 25 years of creating the original ACI 530, the major problem was writing it to reflect the local exceptions, practices and terminology and unfortunately the ASTM standards are rather behind the real world for masonry.

Dick

Engineer and international traveler interested in construction techniques, problems and proper design.

 

[jdgengineer]

I believe they allow you to use strength design for out-of-plane forces on wall because the ASD chapter does bit have any slenderness provisions but the Strength chapter does. However, I don't do a lot of masonry.

I wouldn't be too concerned. The PE exam only has a few masonry problems. Even the SE exam when I took it was fairly light on masonry.

 

[fegenbush]

The new SE Exam, per the published exam specs, has one problem from each of the four materials (masonry included). I have read from another forum that one "unacceptable" is enough to fail the whole test, so a detailed knowledge of masonry design is required.

 

[kylesito]

I agree that it is not a concept that you can blow off. However, I was always taught to use ASD for all masonry and this is what I did on both the PE and SE. I did have a masonry essay question on one of the SE modules but would not have done anything other than ASD.



PE, SE
Eastern United States

"If a builder builds a house for someone, and does not construct it properly, and the house which he built falls in and kills its owner, then that builder shall be put to death!"
~Code of Hammurabi

 

[jdgengineer]

Sorry I think I may have been unclear. I wasn't saying not to study any masonry, only I wouldn't get hung up on the slender wall provisions on the PE exam. If you were taking the SE exam I would recommend studying the masonry much closer, but I still think it would be unlikely they would ask you about the slender wall provisions as they are iterative by nature and thus hard to solve in an exam setting.

 

[kylesito]

JD, I was only referring to not blowing off the slender walls portion so I think we are on the same page. Your thoughts on it are correct...it's probably too involved for a typical exam setting. I could only see there being a cursory problem on there that requires you to go to that section but not work through an entire example.



PE, SE
Eastern United States

"If a builder builds a house for someone, and does not construct it properly, and the house which he built falls in and kills its owner, then that builder shall be put to death!"
~Code of Hammurabi

 

[kylesito]

Should add...one of the best references for masonry I found (once you understand the code and underlying concepts) is the CodeMaster published by SK Gosh. Pick one up and it will be a good equation sheet for you to reference.

PE, SE
Eastern United States

"If a builder builds a house for someone, and does not construct it properly, and the house which he built falls in and kills its owner, then that builder shall be put to death!"
~Code of Hammurabi