Hiring a bridge engineer? 3

[bridgeDisciple]

I have a startup company that needs bridge engineering design services. Its unusual in that we seek a modular bridge whose design is not site specific, and is robust enough to be deployable within a region. Thus we need a good design up-front, and then will need some follow-on work for each site application of it. So we seek an on-going relationship.

But finding s bridge engineer is proving to be a challenge. Most either work for a state DOT, or a huge AEC company who are not interested in our tiny little startup. Steel bridge engineering seems to be a specialty, and modular bridge design also. Finding overlapping expertise is tough. And i'm sure we don't know where/how to effectively look.

Anyone have advice for how to locate qualified bridge engineers who are free to work for us (for hire)?
Is there a list somewhere that i have not yet found? Or a professional trade organization that can do referrals? Does this forum have an associated job board where we could post our need?

 

[rb1957]

Knowing where your are might help others respond better ...


"Hoffen wir mal, dass alles gut geht !"
General Paulus, Nov 1942, outside Stalingrad after the launch of Operation Uranus.

 

[JoelTXCive]

Another avenue worth looking into......

Have you tried using Contech or other pre-fab bridge companies?

They have semi-customizable steel bridges; and will do the design for you in-house. All you have to do is design the foundations.

 

[AZPete]

Will it be a "machine" or will it be a "civil structure"?

 

[bridgeDisciple]

to rb1957
Good point. Our market is the continental US.

 

[bridgeDisciple]

JoelTXCive,
Good thought.
Yes prefab pedestrian bridge manufacturers is the only place so far we have made progress. Their process generally assumes a specific site, which is a barrier to quoting. Also they basically re-parameterize previous designs and are less motivated to engage in a seriously custom design. It then locks us into using them for manufacture, which is typically manual. We will likely need automated manufacture of the modules for high volume and production rate and lowest unit cost. US Bridge is the only vendor we've found who is already set up for automated production.

We've also looked at Bailey bridges. But they tend to be too bulky and expensive - not optimized for our need. A module about 40 ft makes more sense than a single 10 ft truss panel.

 

[bridgeDisciple]

AZPete,
I'm not sure i understand the vocabular well enough to answer accurately. I think "civil structure". Our bridge modules are to provide elevated guideways for lightweight people movers (on public lands).

 

[human909]

AZPete,
I'm not sure i understand the vocabular well enough to answer accurately. I think "civil structure". Our bridge modules are to provide elevated guideways for lightweight people movers.

Startup?
.."Light weight people movers"?
....."Elevated guideways"

This sounds awfully like:

https://www.youtube.com/watch?v=ZDOI0cq6GZM

 

[bridgeDisciple]

human909,
I love it !
Actually the drawing looks a lot like an Intamin P6.
Link

No, we're talking smaller.
Link

Just kidding. Something in between. Similar to this
Link

 

[Lomarandil]

BridgeDisciple -- I know a guy who would enjoy taking this on -- aligns with some other work he's done. Click on my profile to get in contact with me, and I'll send you his info.

 

[CrabbyT]

As someone who used to design farm structures, I think you're going to have to put a lot of thought into this. Designing a one-size-fits-all bridge is going to be challenging. Places like California and Chicago will require this to be stamped by a licensed SE (not a PE). It was easier in agriculture due to the relaxed permitting requirements.

 

[LittleInch]

Isn't that simply designing different spans between supports for a tubular frame construction. Say 40,50, 60, 70, 80 ft

Theme park ride designs come to mind.

Or like this in Heathrow. simple concrete section

https://www.youtube.com/watch?v=BF1RVbnzPfs

Built by this lot

https://www.ultraglobalprt.com/

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[bridgeDisciple]

(LittleInch)
We have reached out to multiple roller-coaster design companies. Most (Intamin is the exception) are allergic to public transit. Dealing with one theme park owner is so much simpler than dealing with a multi-jurisdictional public entity. Plus the sedate ride characteristics are boring to the engineers compared to loop-d-loops. The frontier we push is cost-effectiveness. The frontier they like is physics/thrills. But their annual conference is next week in Orlando and i'll be there.

The Ultra PRT at Heathrow uses traditional 2-point tracking (electric golf cart with a shell) from steerable wheels on concrete. That relies upon friction and vehicle weight for stability. So the bridges must be more substantial - costly. But yes, they can use common concrete bridging.

Roller coasters use 6-point tracking. They are geometrically locked to the rails (called "captive bogie"). They can weigh almost nothing and still track reliably (even upside down). So they can make for a much lighter & cheaper bridge. As you point out, nothing but a round pipe in some cases.

 

[LittleInch]

are these bridges just for getting over things like roads and railways or is this all the way?

Constructing things on the ground is much cheaper and less intrusive?

I know this isn't your question but it's quite an interesting topic.

Are you looking at 2/4 person pod type things or bigger vehicles?

These guys are talking 12 to 16 people versions.

Nice graphics for sure, but not sure about the economics....

https://urbanmass.co.uk/

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[gte447f]

bridgeDisciple, I understand that you are trying to be intentionally vague to protect the specifics of your startup, but it makes it difficult to provide you with any useful feedback. If the links above are representative of the type of structure you are dealing with, then I would say those are very significant structures and will require a very high level of specialty knowledge and expertise. In other words, prepare yourself to bight the bullet and hire a specialty engineer (think amusement ride/disney experience) or a large, reputable, nationally known structural engineering firm.

 

[BridgeSmith]

I think gte447f makes a good point about this being a specialized design field. I'll add that you're unlikely to find an engineer willing to 'fly solo' on something as 'out of the box' as this. Anyone who is conscientious about their work is going to want another engineer or consulting firm to review their design.

 

[bridgeDisciple]

(LittleInch)
UrbanMass came onto the scene about 18 months ago. I've not heard much from them since. We'll see if they show up at the annual trade show at the end of this month.
Link

The one think i note about the UrbanMass design is the "cantilevered" vehicle support. We were the first PRT company to publish that concept (and took some skeptical response to it). But simple"

Citytram's theory of the case: Economics don't work without ridership; public transit (in America) fails because it is slow and inconvenient; to be successful you need to provide transit that is speed and cost competitive with cars; that means a dense taxi system (no waiting, no sharing; point-to-point network); you can't go faster than cars if you share the roadway (and control system) with them; so grade separation is required, and elevation is cheaper than tunnelling; so EVERYTHING must be done to keep the cost burden of bridging to a minimum. It IS doable.

Our pods carry 3 people. We use a synchronous control system to guarantee minimum headways for limited/minimal loading on the bridge spans. It is a constant speed system (conveyor-like) to guarantee maximum throughput and minimum energy. It is elevated everywhere (climbing hills wastes energy and requires more power which adds weight). The exclusive guideway makes Vision Zero possible, and you can't do that on the ground without blocking existing ground level flows. RoboCars will fail to live up their safety hype because of this reality. They will never be as fast, as safe, nor as energy/emissions efficient as PRT.
1- Cost Informed Transit (21 min) Link
2- Speed (12 min) [URL unfurl="true"]https://vimeo.com/694293410[/url]
3- Bridge Costs (31 min) [URL unfurl="true"]https://vimeo.com/694274246[/url]
4- Structural Requirements (26 min) [URL unfurl="true"]https://vimeo.com/703074520[/url]

 

[bridgeDisciple]

(gte447f and BridgeSmith)
I'm sorry if i've been too vague. I was trying to be concise, not evasive. Hopefully my reply to LittleInch fills in some details. I do appreciate how doing a general/re-usable/re-locatable design, and for a modular bridge, and for a non-automotive one is a bigger challenge than designing for one specific context. I already did expect we needed a licensed SE. I had even come to understand there are lots of SEs that do buildings or pipes or tunnels and never touch a bridge. So i expected we needed a bridge engineering specialty. I'm not opposed to large SE firms. I just don't know how to find them except as attached to large AEC firms that charge absurd rates we could never afford, or simply are not interested unless you have a go-ready project priced in the $100Ms. The problem with "specialty firms" is if you don't fit well into their "specialty" then its a no go.

A big part of our problem is my own ignorance in this space. There are thousands of firms, all doing "engineering" but all of which are doing different things. Then there are legal requirements. With respect to bridging, many are specific to and limited to the automotive (AASHTO) space. The civil construction industry is still largely bespoke. Costs and economies of scale demand it become more industrial (pre-fab), but that de-construction of things has not yet happened. So coming from the outside to this industry, finding out who does what, and what is closest to what we need is a big lift.

We want a modular bridge unit, made of steel, that can be robotically prefab manufactured in large volume at a rapid rate with reliable quality and transported to site and quickly installed (lifted, bolted/field welded into place). The loads are highly controlled and very low - less than pedestrian walkways. We wish it to be deployable in any suburban area within the continental US, along/above suburban arterial roadways. Our interest is in optimizing these units for constructed cost.

Does that description help? What specialty do i need, and where might i best find it?

 

[gte447f]

Yes, that description does help. Let me ask, for a typical project installation, how many linear feet/miles of this elevated track/bridge structure would you erect, and at what average height above the ground?

 

[bridgeDisciple]

(gte447)
We expect a gridded system to be common. The formula is w(h+1) + h(w+1). So a site covering a 4x3 mile area with a 1-mile grid will take 31 miles of guideway. If its a 2-mile grid its only 21 miles of guideway.

It needs clearance above existing cross-road cantilevered traffic lights. In municipalities already using the newer fed specs, the tops of those lights are about 19.5 feet. We are targeting bridges with about 21 ft clearance.

Our throughput is 4x to 7x that of a single lane of roadway. So we could handle all the traffic on most such arterial roads. But our target is to be profitable by taking just 15% of the cars off the road via customer (voluntary) choice.