Fellow Engineers, Modelers, Bentley Operators, etc.
Last year in July 2017 at the 9th International Visualization In Transportation Symposium I presented an abstract detailed an alternative approach to working with Corridor/template design.
This approach is called "3D Linear Method". It is the complete opposite on what Bentley encourages in their teaching workshops, and consequently the opposite what is demonstrated by every major Department of Transport I have encountered. A brief outline on how it works:
Instead of single templates/corridors spanning the whole width of each roadway alignment, the corridors are broken up by element. 1 corridor per curb, lane, shoulder, guard rail, end condition, wall, barrier, etc. Each piece is connected to each other, eventually connecting directly or indirectly to control lines.
While this creates 100's of extra corridors, the advantages make this technique far superior to the designer, and end user (client of contractor) than the current approach for the following reasons:
1) Templates are simple, easy to create, and have no complex display rules so they are functional for the novice user
2) The same template can be re-used 1000's of times, across any project, making the data consistent 100% of the time, giving reliable consistent symbology when the data is visualized
3) The consistent nature of common templates used always simpler digital quantities to be extracted, as similar objects can be collected by symbology
4) Changes are more manageable - change only the parts you need to change, and the connectivity of all the other corridors will automatically be adjusted
5) More than 1 user can work on the same road in the same section at the same time as everything is broken into smaller pieces
6) Simpler to train - for those unfamiliar with a 3D environment, this 3D Linear Method is identical to criteria
7) Processing is substantially reduced - it is quicker to process 100's of small corridors with no complex rules than 1 or 2 massive corridors with lots of display rules by a factor of 10.
This technique has been implemented across every designer I have worked directly with in Illinois over the past 4 years, and there has been 3 distinct reactions:
a) Those with some 3D knowledge embraced it fully, recognizing that this is the ONLY way to utilize the software, no exceptions
b) Those with minimal or zero 3D knowledge dismissed it entirely, citing "This is not the way Bentley teaches it"
c) Those with medium experience recognize its power, and use a toned down version of 3D Linear method - they build templates that span all lanes, 1 for shoulders, then 1 for end conditions, for example.
Overall it has been received positively from those who understand the software's limitations, and widely used across Illinois Tollway I-294 project currently underway.
This modeling technique has caused quite a controversy here from the State Government in Illinois (IDOT) due to the radically different approach. So I wanted to hear from the greater community regarding this technique.
If you would like to contact me directly about this, feel free to do so:
Alexander Badaoui, PE: P 312.467.0123 | abadaoui@terraengineering.com
The presentation I made showing this in more detail is found here:
https://www.youtube.com/watch?v=Se8oQvVNw_w&feature=youtu.be
The attached PDF is a summary of the abstract presented.
https://www.dropbox.com/s/7jwku3ns2cu7aql/Abstract%20-%20Developing%20Visualization%20Transportation%20Models%20-%203D%20Linear%20method.pdf?dl=0
This was geared towards a non-technical audience. The following power point below is more technically driven, detailing how the naming convention operates in Illinois:
https://www.dropbox.com/s/dxq9nrm5z5vc63i/2018-03_AB%20to%20IBUG_May%202018%20-%20Part%201.pptx?dl=0
Thanks in advance for your feedback on this technique.
Alex,
Thank you for sharing.
It looks like we have at least 2 ways to skin the cat. In one go or strip by strip.
The advantage of the 3D Linear Method is assembly line production; where is that automation button? Scripting anyone? If the operations are so simple and repetitive, they must be automated.
We have a few legacy MX users around, they've started on *nix machines. These guys cannot pick up C3D, nor Inroads, they think different. It's a pity to fire them, so it looks like this way we can get them on-board, moreover we can benefit from their experience. Win-win!
Will try it out and see how other people reacts.
Regards,
Val.
Good luck Val. Let us know how it goes.
Regarding your automation requests, I have mentioned earlier in this post for ANY Bentley person to make a comment on this technique. If someone knows how to tag a Bentley user so they can see this, and provide official feedback, please do so. It is very obvious from the comments that the designer community see this technique as a more functional solution than what is encouraged by Bentley in template and corridor creation. And since this is the case, perhaps Bentley should consider adjusting their software to fit with this method.
Hi Robert, It seems like more and more clients are asking us for earthwork quantities by construction stage. For instance, NB lanes one and two may be stage 1, Southbound lanes 1 and two may be stage 2, and the median may be stage 3. Is there a way that you can split up the earthwork numbers if you use full templates?
Thank you Rob for a detailed response to this post.
You make excellent points, especially in regards to how the template editor operates. To the new, or infrequent user, the interface in constructing a functional template that will not only build an accurate 3D model, but will aid in plan production, is a daunting task to say the least.
The example you have presented appears to be a hybrid-Linear method, in which some parts of the model are designed via a large encompassing template, and other parts are designed by smaller component-style templates. While I do not discount the viability of a hybrid method for certain applications, there are gaps in the model presented that can never be practically completed using large encompassing templates. They must be created with smaller components, or the single template becomes what you describe as a “GOD” template.
The design industry in the US (architecture, Civil Engineering, Landscape Architecture, etc.) is moving towards paperless digital delivery. The users who have been inclined to agree with or like the approach are predominantly MX users, and those users are predominantly from regions where the 3D model is already the deliverable. Gaps and missing details in the model are not considered acceptable and models needs to be as complete as possible. Any gaps in the model could be taken advantage of during construction resulting in costly change orders.
In Australia, where I come from, the model is the FIRST deliverable, and plans follow second. The model detail overrides the data on the plans if there is a discrepancy. From my experience in US, the industry is not there yet as a whole. Some regions are further along than others. In order to develop a complete model, there will always be parts of the model to be broken up into its smallest components. A singular template approach is limited at best.
To directly address your concerns:
Managing thousands of objects –
Any project of significant magnitude will have 1000’s of objects. That is inevitable. Even smaller projects, as the model becomes more complete, has 100’s of components regardless of using multiple corridors, or a singular corridor, because of the detail required in non-regular parts. These areas include (but not limited to): ADA ramps, driveways, curb depressions for ramps, guard rail that does not follow any alignment, etc. So in the end, no matter the project size, there will be many objects to manage because of the detail required to make a complete model which is what the industry is gearing towards.
Considering the life cycle of the project –
I agree with your statement regarding the planning stage. Large, singular templates giving general detail is the most functional approach to plan multiple options. This gives a great general understanding of the impact of the project such as right of way, impacts to drainage catchments, structural requirements, etc. When transferring a planning model to a detailed model, expecting the structure of templates and corridors used before to remain largely the same is obtuse. In my experience, the firm performing the planning design (some call it Phase 1, some call it concept design) is not the firm performing the detailed work. There are exceptions on small projects, but not many. Therefore the firm doing the detailed design will reconstruct the project to verify the work, and end up changing it, most likely due to new survey conditions or new client requirements that were not identified during planning. I have not once seen any project where the concept design did not undergo a significant change during detail that required previous work to be abandoned. My experience is limited to the following though: South Australia, Victoria, New South Wales, Hai Phong Vietnam, Kabul Afghanistan, Northern Illinois, St Louis MO and Dallas TX.
I have one final point on using large templates for regular parts of the project, and smaller ones in the micro detail:
Projects change details all the time, especially the larger ones. Bentley software, both SS4 and Connect, limit the use of 1 template library per workspace. With multiple users on a single project, all modeling, they can not edit templates at once. If they are working on ProjectWise, the issue is worse as a user can edit what they think is the template library, and only be the local cached copy. Therefore they will make a template that is inconsistent with the central library, and if someone were to re-sync the template, all their work is gone. The less time users have to spend building new templates, and just use them, the better to avoid these conflicts and inconsistencies. Under 3D linear method, all the components are created to give you the building blocks required to build 99% of the project and you minimize the time building those unique templates to fit a unique scenario.
Thank you providing a list of software enhancements. Petitioning Bentley to make those changes would benefit all users. Additional software enhancements that would aid in modeling include:
I have developed work-around practices for all these items, but having the software updated with these enhancements will greatly improve modeling using either approach.
Just my 2-cents about managing hundreds or thousands of objects with the linear method:
If you use full templates like Bentley teaches then sure you have less corridors BUT many more controls to manage per corridor than if you used Linear modeling. For instance, I used the templates that IDOT supplies us (that most likely Bentley built) for a two-lane divided highway. I have 11 point controls, 18 Parametric Constraints, and 2 end condition exceptions. That is 31 Items to manage using a full template. I have spent countless hours going through controls like these to diagnose why things are not behaving like I would expect. It is very daunting trying to manage all the pavement, curbs, ditches, sidewalks, etc all in a single group (corridor).
With Alex's linear modeling for this section I would need to make 14-16 corridors to make the same thing that 1 Bentley template would make. However, there typically will only be one or two controls per corridor. This makes it much faster/easier to go in and modify a control because it is much easier to find what you are looking for. It so nice to see that say the curb doesn't look right so you click on the curb look at the 1-2 controls and adjust. Boom your done. Also with modeling one element at a time I am much more aware that those items are following the rules. By rules I mean is everything following the superelevation, are my rollovers working, are ditch widths correct. You get the opportunity to check these one at a time to be sure they are correct. A template would just do it all at once and you are more likely to miss something.
So either way, I find there are about same amount of items to manage. For me, it makes sense to simplify how those items are controlled. Splitting up templates into linear models achieves this.
With Alex's linear modeling, I can build anything using his technique. When the job nears completion I find that I have a much more consistently built and stable product. All the corridors are laid out the same and there is no guessing how something works.
Using full templates, I have to decide if a certain template can do what I need it to do. If it doesn't, then I have to create one that does. All waisted time. Some of the convoluted controls I have to add to get a template to do what I need to do can get very messy because you are fighting to get a typical section to do something that isn't typical.
Robert,
I understand what you are saying a about concept and final design. Try this though. Take the model described in your post. Create corridors for pavement right and pavement left. Then create corridors or linear templates for end conditions right and left (this includes curb, gutter, sidewalk, guardrail and walls). That is four corridors instead of one. You will find that this will give you more flexible in your design. No more display rules , you can change end condition without affecting the pavement sections. Also you can use the same templates over and over again on different areas or projects. Another plus to this method is the fact new users don't have to learn how to create massive templates right off the get go, they can use a library of simple templates you developed for them. Finally you can split the work out more easily on larger projects. I have found that modeling the pavement separate from end conditions increases processing tremendously.
This is the problem that Bentley's Concept Station has. Bentley has developed hundreds of templates to address every situation. 4 lanes with a ditch, 2 lanes with a sidewalk, 3 lanes with a median and wall, etc.... All they need are 20+ pavement templates for lane configurations that can be reflected right and left. 20+ templates for end conditions that can be reflected right and left. The end conditions could be controlled separately in order to add or change sidewalk, guardrail , ditches, walls etc...
Please take the time to examine this method. I know for complex interchange and grading work that separating the corridor modeling into separate pieces really gives the designer a lot of control.
Yes, in OpenRoads Designer you can use Named Boundaries for earthwork phasing/staging.
Thanks Scott. We are actually using SS4 open roads (non-connect) software. Is there something like "named boundaries" in what we are using? Power Geopak 08.11.09.878
Dennis unfortunately, named boundary is a new type of clip volumen developed in MicroStation Connect edition for helping to build the plan production corridors in OPENROADS and OPENRAIL DESIGNER connect Edition, but this tool is not integrated in SS4 open roads tech non in powercivil (inroads) or powergeopak