R&D ideas for structural engineering 10

[daranguiz]

Hello everyone,

Large open question:
If your company was able to give you a lot of money to launch one or more R&D programs focused on structural engineering, what subject would you like see on the list?

 

[London]

For me, one stop shops where information from various vendors can be compared.

It would be much harder to implement successfully than it first sounds, as it could easily end up as a bad advertising website.

Currently, when sourcing/specifying products, I start with a vendor, then browse their catalogue for items. This approach is conservative when trying to find new alternatives to a problem.

 

[JStephen]

When I was in school, there really weren't any problems that seemed that interesting for master's theses or PhD dissertations. Since I've been in the work world, there have been a number of questions that come up from time to time that would work for those, and of course, I don't have the time or inclination now.

One of them is circular sloshing in a cylindrical container. If you take your coffee cup and move it side to side, you get normal sloshing. If you move it in two directions at once, the normal assumption is that the sloshing is the sum of the effects in each direction. But in fact, you can get effects that are not the sum of those effects, such as sloshing the liquid around in a circle. I suspect damping is lower for this kind of motion as well.

 

[FishTheStructure]

JStephen,

Perhaps I don't completely understand what you are trying to describe but I don't see how moving "in two directions at once" is different than just moving in one direction (in the resulting vector of the two directions at once)? i.e. What does "moving in two directions at once" look like?

Great spirits have always encountered violent opposition from mediocre minds - Albert Einstein

 

[DaveAtkins]

Interestingly, perhaps the most useful information would pertain to SMALL buildings and structures, not large ones. For example, I would like empirical information on:
* Strength of wood diaphragm where blocking is missing at sheathing joints and between truss heels
* Strength of GWB ceiling diaphragm
* Strength of roof diaphragm clad with corrugated steel roofing but without chords at perimeter (wood purlins work together to resist compression and tension)
* Strength of unblocked wood shear wall
* Overturning capacity of wood shear wall without hold-downs (with and without window and door openings)
* Strength of CMU jamb at overhead door opening to resist lateral load
* Strength of concrete slab on grade to act as tension tie for PEMB frame

DaveAtkins

 

[calvinandhobbes10]

--Concrete high-rise column shortening with the purpose of developing design guides. Plenty of research is underway, plenty more is needed.
--Splayed-strand pile to pile cap connection tension capacity.
--Impact of wind drift relaxation on finishes and serviceability in low-rise commercial construction.
--Masonry back-up control joints how they truly behave and appropriate detailing.
--Agree with London about consolidated resource for proprietary construction products which come out all the time but have significant lag for adoption to the idnustry. Currently Google is my resource for this.

 

[JStephen]

Fish-
The effect I'm getting at is whether the fluid actually moves in a circular motion or just oscillates back and forth. If you consider the X and Y components as independent (which is essentially what's done), you never get circular motion in the fluid. But if you slosh the liquid over to one side, then while it's more to one side, you move the container at 90 degrees to that motion, you get circular movement. Easy to do with a cup of coffee, but not an effect considered in seismic design that I'm aware of.

 

[TehMightyEngineer]

Strength of ungrouted, uncompressed, male-to-female precast concrete shear keys, keyways, and shiplap joints.

Professional and Structural Engineer (ME, NH, MA)
American Concrete Industries

http://www.americanconcrete.com

 

[Guastavino]

I'd like to see research done on how many structural engineers interpret the building code correctly versus incorrectly. Seriously though, have someone review plans submitted to building inspections and just get an idea of how many apparent code violations are on each set of plans. Sounds snarky here, but point of the research would be, "Is the complexity of the code out-pacing the understanding of the engineer"? In other words, are the codes changing so fast and getting so complex that it's too difficult to expect people to follow.

 

[WARose]

A fatigue study of concrete anchors (especially in cracked concrete, where info seems to be lacking) for high cycle loads.

 

[cliff234]

njlutzwe,

I have done this research (observations in my 40 years in the profession). The answer is "yes".

 

[Lomarandil]

This may be pie-in-the-sky, but developing a rational approach to improve post-installed concrete anchor capacity accounting for present (not specialized) reinforcement in the concrete, without adding additional complexity to ACI App. D

 

[TehMightyEngineer]

I'd like to see research done on how many structural engineers interpret the building code correctly versus incorrectly. Seriously though, have someone review plans submitted to building inspections and just get an idea of how many apparent code violations are on each set of plans. Sounds snarky here, but point of the research would be, "Is the complexity of the code out-pacing the understanding of the engineer"? In other words, are the codes changing so fast and getting so complex that it's too difficult to expect people to follow.

This was actually done; I can't seem to find it now though. It was some design challenge study done by ASCE or SEI or someone where there was a task given for people to submit designs to and they were rated. I can't recall the details but remember that there was a shocking high number of respondents who failed to correctly design anchor bolts. If someone could find it that would probably go a fair way toward answering your question.

Professional and Structural Engineer (ME, NH, MA)
American Concrete Industries

http://www.americanconcrete.com

 

[JAE]

My R&D project would be to hunt down and gather all the professors, researchers, and code writers of ACI Appendix D.
Then lock them in some old wood stocks, outdoors in northern Minnesota in January.
Have several architects shouting in their faces for hours at a time until they yell:
[blue]"I confess!!!! I confess!!!! We made it complicated and ridiculous just to torture structural engineers and make us feel superior!!!!
Forgive us and please take those architects away!!!!" [/blue]

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[IDS]

1. The effect of differential temperature on reinforced concrete cracking and deflections.

2. The effect of ratcheting mechanisms on reinforced concrete deflections and shear capacity (especially for sections with little or no shear reinforcement).



Doug Jenkins
Interactive Design Services

http://newtonexcelbach.wordpress.com/

 

[msquared48]

How about a fatigue study of Engineers?

Mike McCann, PE, SE (WA)

 

[gravityandinertia]

@msquared48

I believe from reading on these forums the fatigue life of an Engineer is about 40 years. I can't tell you how many cycles that is or the standard deviation, so I guess you're right, there is more work to be done.

 

[RWW0002]

I agree with DaveAtkins that there could be alot of value in trying to understand how many smaller buildings with some relatively complex features behave. With the rise in mid-rise wood construction, there seems to have been a resurgence in wood analysis research, but all geared towards large and very complex structures. This still leaved small and medium-sized wood structures without much to go on (Im thinking low rise structures with wood-framed floors and wood truss roofs that generally have plan offsets, irregularities, and construction standards that do not always meet the letter of current codes - yet seem to behave well over time).

I would add the following to his list (many of which are discussed here all the time).

-Behavior of unblocked roof diaphragms without a continuous chord member.
-Effect of a ridge vent on blocked and unblocked diaphragm behavior.

 

[Guastavino]

@tehmightyengineer

I think I might know what you're talking about. SEI does trial problems, and I sat through a seminar with them where they tested code interpretation and found widely varying answers. Here is a link to the committee.

It's called "Design Practices Committee"

http://www.asce.org/structural-engineering/sei-business-and-professional-activities-division/

 

[Trenno]

I'm just waiting for KootK's reply...