Thursday, November 30, 2006

...for in the final analysis...

What's happenin' everyone!

Tests and Projects beating you down? That's okay, we'll procrastinate with a design session Friday night and a full day of Chrome Ollie stuff on Saturday!!!

Okay, so, here is the earth, I mean...We'll be meeting Friday night at Matt's place on Brandywine to discuss the options we have to analyze on Saturday. Our priliminary analyses show what are the likely best cases for all bridges. Friday night we will finalize all design features for each bridge that WILL be made for each design. So, for instance, if one bridge has a shallow deck, it will have a wide lateral truss, if it has a deep deck, it may have a tri-lateral truss, or we may put more DK to DK laterals in it (separate members). Either way, these decisions need to be made so we can get a dead nuts accuracy on what features will be fabricated for each bridge. Most importantly, we'll talk about constructability of each design.

On Saturday we will of course be moving our gear down to the fabrication level below the Loft so the construction boys can have their way with the wall and the staircase. This will only improve productivity. We will make brand new models from up to date DXF's in SAP, and analyze our previously recorded best results for each bridge. Right now there are 6 main designs (including a new one we haven't analyzed just yet) we are going through, each has 2 flange variations, so that makes 12 models we'll have to make from scratch on Saturday. Be ready to get into it, we may have to assign 2 bridges per person.

Matt will be in charge of making the DXF's. Team members, especially returners, will be responsible for making decisions on what will go into each design. Everyone will be responsible for analysis on Saturday. Let's be methodical and cold, and get it done with a numbing efficiency. We need clear numbers for each bridge so we can DECIDE.

After analysis, Phil and Matt, and anybody who wants to join in, will be TIGging model bridges out of steel. Each model will be approx. 2 feet long so we can get an idea of how everything looks in 3D (i.e. structural behaviour, assembly etc.). Should be fun. Phil and Matt will coordinate getting more steel to fabricate the models, which will consist of making a simple CAD model, getting dimensions and sizes set, cutting, grinding, and TIG welding the suckers together.

Okay, that's it, get ready to put forth one final analytical effort. ANY NEW DESIGNS ARE WELCOME, IF YOU HAVE AN IDEA, DON'T BE SHY.

It takes a vision to start something wonderful...

...but engineers to finish it.

Wednesday, November 22, 2006

Getting Down to it.

Last Saturday, or Causeway Saturday, we took a closer look at some of the trusses we've been analyzing. The Monster looked better with slightly modified flanges on the deck, it came out lighter and stiffer, so kudos there. The others were about the same, a little lighter, but not much else.

We also tried analyzing a multiple beam set, which didn't do so well, but if it's stiff enough, it might make it worthwhile. Matt's going to buy the beams for a field test as soon as he can (maybe...$$$ concern).

This Tuesday we had a Construction Rules Quiz, and it is evident that new Team members need to read the Rules more often and become more and more familiar with them as the season progresses. We also need to learn how to speak up! It's okay to talk and be vocal, if you aren't sure ask. Time to break out of the mental shell and be a real engineer. Talk, and with volume! ;-)
After the Construction Quiz we discussed some of the best bridges. New bridge ideas are dwindling, so we'll have to decide what it is we want to do with the ones we have. We have to think about, and possibly tinker with the assembly design, all of the following:

Constructability - # members, # bolts, reachability of certain nodes, risk potential, assembly location, connection type.

Lightness - weight of connections, weld weight, what needs more wall thickness, what can do with ultra-thin wall (i.e. web, wide OT)

Stiffness - Depth vs. beam-like truss vs. how stiff can we get a beam.

Lots of discussion coming up before we decide, be prepared to listen and state your beliefs.

Wednesday, November 15, 2006

11/14 Notes and about Saturday 11/18

Hey Chrome-O's,

This Tuesday Jessica and Matt summarized what we've analyzed so far:

Bis Vs
Chichen Itza

As of right now, the Everest Truss looks too unstable, and has safety issues for construction that, quite frankly we shouldn't have to worry about. We're trying to get a solid structure and minimize construction risk, as our construction score counts for quite a bit this season.

We also noted that weight is a big factor in our structural score, so all design will be on a diet plan to a certain extent. Roughly 75%, 25%, weight to deflection (if our deflection range is reasonable on average)

Think about construction in the meantime, we have to put this baby together in our best time ever if we're going to win at Mid-Pac. The 2005 effort was our best yet at 3 minutes 38 seconds, with an immense amount of practice mind you. Last season's effort was also very solid, but imagine how fast we'd have been if we didn't rebuild the entire overtruss after Mid-Pac. That's 3 more weeks of practice!!!

THERE WILL BE A COMPREHENSIVE CONSTRUCTION QUIZ ON TUESDAY NOV. 22ND!!! So be ready to answer question correctly -- there may even be rules pertaining to the clarifications on the AISC NSSBC competition page found here:

(follow the links to student design competitions)

Well, it's no secret to those that've been showing up. We're getting very efficient at analyzing, and with the turnout, we are ahead of schedule. This weekend, and this weekend only, will be the last effort to try new things. The weeks following will require some fine tuning, and narrowing the decision. Jessica and Matt will have models ready for input and analysis - there should be about 4 or 5 workable designs.

Sac State will be in town this Sat. We play at 1:05 p.m. at Toomey Field - All current students can get free tix so long as they show up early and check in with Aggie Pack on the East Side of the "Stadium" - 11 am would be safe, maybe even sooner, don't know how crazy everyone is going to be. Gates open at 11:45 a.m. - this game, the 53rd Annual Causeway Classic, will be televised (pause for laughter of the I-A university football schools reading) so that's an added bonus, tape the game, maybe see yo'self on tv.

Our analysis checks for this Saturday will include:

Monstro - with modified deck flanges, I-Beam NDSU style I guess you could say, but the geometric centroidal depth in SAP will go up 1/2". Sweet.

Big Vs - again with I-beam like tubular flanges.

Chichen Itza - with the new flanges again.

Matt will also develop his "Lowrider" beam deck - it will be a special case, and hopefully, he can organize a trial loading of the PDM Model very soon to see if it's worth it. This will be our first beam-style analysis.

BASIC rule of thumb for analysis to final product, is that the shallower your bridge is, the smaller the margin is for error. Deeper bridges tend to deflect closer to that analyzed. We may have to elevate the pin connections atop the piers for the beam to be effective.

Okay, ramble on! I know.

See you Saturday -- again, good luck with continuing mid-terms.

And so we design and analyze on! Remember to read the construction rules AND clarifications.

Having dreams is common, being crazy enough to make them reality, that's Chrome Ollie.

Saturday, November 11, 2006

Two new ones 11/11

Sweet day of analysii today.

The Monstro and the Everest were analyzed today. Both have their good aspects, especially Everest, it's very buildable with a few extra bolts at midspan. Monstro looked good despite it's lack of depth.

On advice from Jessica, we'll try the Big V's a bit shallower to see how it performs, we need to reach up top, and quite frankly we've only got one 6 footer on the Team right now.

Tuesday, November 14th at 6:10 p.m. is our next meeting. We'll meet in the Chrome Ollie Loft in 1203 Bainer Hall. Discussion will include the numbers for all four trusses we've looked at so far, we need to talk constructability concerns, lateral arrangements, and sequence, because that will most likely determine the final decision. After making a decision here in the next couple of weeks, we need to concentrate on building the best bridge possible and then get it ready for practice at San Jo this April.

On the football front: NDSU killed Cal Poly, Sac State lost to Matt's hometown PSU Vikings. The Cal Poly loss is bad for the Aggies, as it makes Univ. of San Diego look better to the I-AA playoff committee. UC Davis has already agreed to bow out of the Nov. 25th contest with the Toreros in the event that they make the playoffs (we are playoff ineligible until next year). Right now we're at 4-5, and a win against Sac State and USD would ensure our 38th consecutive winning season. So everybody needs to show up at Toomey on the 18th for the 53rd Causeway Classic, after that, it's in the committee's hands as to whether or not USD will come to town...not that anybody will be there, it's Thanksgiving.

Design/Analyze on...

p.s. - Granite just chipped in for $2000 - this means we might be able to buy those test girders from PDM. Matt will get the quote from PDM on that, while Jessica checks with Dillsburg on those sizes to see if we get to go into a deeper tinker on the best choices so far.


Wednesday, November 08, 2006


This may have been previously stated, but here it is again.

Don't know who's reading this, if anybody at all...from Davis let alone across the country.

DON'T USE STRUTS (or more simply - angled braces going from bottom of pier to underdeck and/or up into the truss). All they do is kick out the bottom of your free standing foundation and cause more rotation/moment into the critical areas at midspan. Keep it flat, even hinged if possible. Do not strut, no matter what John Travolta says, it's a waste of time and energy. Focus your efforts into keeping a truss or a beam as flat as possible. If you do anything, batter your piers like they do on highway bridges, do not strut.

Tuesday, November 07, 2006

November 7th

Well, it's election night, if you haven't voted and are reading this at 8:05 pm then it's too late. Shame on you for not voting!!!

Looks like Dems are taking a few more seats, whether or not they gain control of the House and/or Senate we'll see after tonight.

On the Steel Bridge front:

We analyzed on Saturday, November 4th, before the NDSU game (which we lost in heartbreak fashion due to an uninspired 2nd half). The two bridges were the Chichen Itza Truss and the Big V's. Both are very deep and buildable, they both gave great numbers, some a little, ummm, TOO great, so upon further investigation there were definitely some input errors. It's okay though, it was a tough assignment for first time analyzers. Jessica and Matt will reinput each bridge and check the beginning values for each design. In all there were about 40 or 50 scenarios total for all 6 bridge variations of these two designs.

This Saturday, November 11th, we'll be at it again with two new fresh designs, maybe three, if Matt can find some time in an ever-expanding schedule (thanks Thai Bobby). They'll be much, much simpler, so the new analysis team can get some confidence, but don't think they're insignificant, because they may very well end up being our design choice.

So, Saturday, Nov. 11th, at 10 a.m. in the Chrome Ollie Loft of 1203 Bainer Hall.

Take it easy, good luck with continuing mid-terms!!!