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.
What led me to this discussion was actually the aforementioned difficulty of creating complicated templates. As a beginner to 3D modeling, I've been trying to follow a lot of tutorials that are out there and have managed to learn a thing or two about creating corridors, template drops, end conditions, etc. Nothing I've created so far, however, is very presentable. Tying different corridors together, especially at intersections, has presented a big challenge. I do know enough to see that this 3D linear method can save a lot of time and flatten the learning curve, and I'm eager to try it.
Got 2 questions for you, Alex:
1) How do you suggest beginners to learn the method? I understand the Lego concept (the why), but am struggling with the specifics of the "how." Do you have a simple tutorial posted somewhere?
2) Seeing that clients may still want to see products created with the Bentley method, do you have any recommendations for resources on the best way to learn?
Hi Josh,
I'm currently working on tutorials for the community, but have developed a series of videos demonstrating the basics of modeling using this technique, from naming convention all the way to quantities. Email me directly at abadaoui@terraengineering.com so I can give you access to the links.
The reason why I have not posted them publicly is they are company focused, specific to IL Tollway Workspace, and are a bit "raw" - my Aussie vernacular comes out pretty strong in them!
To directly answer your questions:
1) The first part to do is establish a naming convention for the following:
Points, components, templates, corridors, alignments, profiles, terrain models and features (although you may have to keep what ever has been given to you via the client - but it is important to study the features and how they operate)
With an established convention, it is now time to build a standard set of templates:
Pavement, shoulder, curb (Left and Right of each type you use), end condition options (Left and right of each condition - example: 1 for left cut/fill, 1 for left graded ditch, etc)
Each template should only contain information of a single element - the pavement template should only contain materials relevant to that pavement section, and have 3 control points - its origin (REF), its outer point (WIDTH) and a control point for slope (SUP).
Below is what we did on the tollway:
https://www.dropbox.com/sh/cl70zubm5b8thy4/AAA5vYFCQjCZ4K7Rvkfx8FOAa?dl=0
This link contains a IL Tollway template library, a guide to naming convention, the full list of levels, features, styles, etc for Tollway workspace and a diagram showing how each template operates with points, levels, and how it comes out on plan.
Since you have no access to the Tollway feature library, you will not be able to see all the colors come out. But this will give you a great guide on how to create standardized templates.
Also in each template are 2 features: XS-ZTP and XS-ZBT. These are open components that trace the top (ZTP) and bottom (ZBT) of each template, that can be used as a graphic filter later to create instant top and subgrade surfaces. Using the corridor stage to create the top and bottom meshes causes massive processing issues, and can crash large files making them useless. Therefore I find it 100% more effective to ALWAYS build surfaces from graphic filters.
2) Contact me at abadaoui@terraengineering.com and I'll give you access to videos.
Regarding clients wanting to still see the "Bentley Method" of modeling - I ask any Bentley official to comment on this post. We have had 6 unique individuals interested, or endorsed this technique. Please, I invite you to make a comment of whether you agree to this technique as the most effective use of your software. And if so, would you be willing to encourage this technique?
This looks very very interesting to me.
We are in the process of developing our template library, and the current approach is for the one gentleman who "gets" how to do that, create a "master" template. This master would attempt to cover all bases, but could be copied and edited for specific project conditions. I'm uneasy about this approach because it consolidates template creation knowledge to one individual - I've seen that fail time and time again as people get sick, get busy, get new jobs...And if there's any reason that one person isn't available, their master template often becomes so much useless junk.
It also doesn't involve the whole team in using the software. I believe we will be better if every has some practice at every phase of the development. Sure there are going to be people who are stronger in one aspect than another (i.e. template guy) but everyone has some knowledge, and the basics to determine how a design process should go.
I'm also a huge fan of portability, and ease of debugging. Giant, all encompassing design templates (be they actual templates or criteria files) are very difficult to reverse engineer or debug. The more complex the process, the easier it is for it to fail. My criteria writing process in Geopak was to have simple, small files that did one (maybe two) things, that were designed to be strung together to create whatever conditions a project required. Two lane road, turn lane, curb, curb & gutter, paved shoulder, gravel shoulder, sidewalk, retaining wall, basic cut-fill, cut-fill with conditions, and so forth. There were a lot of files, but each one was pretty easy to understand. Even when I wanted to make "composite" criteria, I could start with the basics and add in conditions, one at a time from my regular library.
I'll definitely be looking into this approach more.
MaryB
Power GeoPak 08.11.09.918Power InRoads 08.11.09.918OpenRoads Designer 2021 R2
Mary, I have been there too many times. Even after say a month, the person that actually designed the complex template will have trouble figuring out what they did to create it. Lets say they do figure out how to fix or modify it. This usually takes up a lot of time. And all of this is waisted time. In the end you have a big mess trying to get these templates to do what you want. With Alex's method, that wasted time is gone. You just develop your components (curbs, pavement, walls, ditches, etc.) and start modeling. You use those same components on all jobs. There is no longer any figuring out why your template doesn't work. You just run one component at a time and the job keeps progressing. And with such simple corridors, anyone can figure them out. Its easy to teach so you have more people modeling.
If you need more information for the technique, feel free to email me directly at abadaoui@terranengineering.com and I can get you some more resources for you.
And thanks again for the plug Dennis!