Alternative approach to Corridor/Template Design - 3D Linear Method

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.

Parents
  • 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.

  • I agree that any insight in what Bentley thinks of this process would be a huge help.  Is there any reasons that we should not use it?  So far it has been a success in any job that I have incorporated it on.

  • I am sure that Bentley is listening and watching, practically anything that can enhance the use of their software is helping them.

    It's obvious that once the software is released there will be users that will challenge how the software is used. There is no 'one size fits all' scenario, two projects are not the same, nor are two users the same.

    As I have mentioned, the great benefit is that we have another method of using the software, of course if we could get some official support it would be great.

    For now let us focus on how to get the best of both worlds.

  • Hmmmmm....I count only 10 people who have responded here besides yourself, and not all of these were endorsements. I would hardly call that "very obvious from the comments that the designer community see this technique as a more functional solution".

    WE all bring our historical biases to such discussions and they color what we think is useful or not. Anyone with an MX background will be inclined to like your approach. Anyone with primarily an InRoads background will be inclined to scoff because they have long ago become comfortable with the potential complexities of templates. Those with a GEOPAK background will fall in the middle tending to like templates unless they have used site modeler extensively, in which case they will be drawn to your proposed technique. Full disclosure: I originated in GEOPAK and was one of the product managers of OpenRoads. For both the InRoads and GEOPAK crowd, the thought of managing hundreds or thousands of objects makes them throw up a little bit. 

    My philosophy: no one size will fit every person nor every project. I develop linear things like the main body of roadway with a template which covers the entire roadway. I use very few display rules, since display rules are the number one cause of template complexity. (Side Note: I know people, you know who you are, that have built their entire careers on making "GOD" templates which solve every situation, but are indecipherable to the rest of humanity.) But, when I get to things which are not linear then I switch to methods like you describe. These areas include intersections, gore areas, parking areas AND channelizing islands.  I seldom includes islands in a template unless they are truly "typical".  It is much easier to add the island on top of something else when the island follows independent alignments.

    Below is a project I have currently underway. There are 3 corridors with a total of 5 template drops. The mainline template has only 2 display rules to control the presence or absence of an intersection. If this were an urban section then I would use two more display rules to control whether the curb is a full curb or drop curb at entrances.  That's about as far as I go with display rules. The intersections have 1 terrain model and 4 linear templates each in fashion similar to what you advocate. The islands have independent alignments with one template drop each.  


    My concerns with your approach are 1) Managing hundred or thousands of objects is not for the faint of heart. 2) If you consider the entire life cycle of a roadway project then your method is very inefficient.

    Consider the need to develop a model during planning phase. At this phase of a project your method requires X amount of time, where X is the same at planning as it is for final design. With a more normal corridor approach, the required level of detail at planning allows me to create a model in literally minutes.

    Also at planning phase, what happens if you need study 5 or more alternate alignments.  How do you move or duplicate your hundreds of objects from one alignment to another.

    Then finally when project moves from planning to final design, if I take full advantage of corridors during planning and generate a model quickly, I have to abandon that work to  then adopt your method, basically starting over.

    In any case, we must all do what works to satisfy our project demands. What works for me is different than what works for you. I will offer the following suggestions though:

    • A continued Quixotic quest to bend Bentley to your idea in whole cloth will not work, but a reasoned argument for enhancements to the code in support of  your pain points might work. 
    • There is a need for better performance. We should all be demanding progress on this.
    • Stability is still a problem.
    • There is a need to be able to apply superelevation rules to any linear element. The lack of this capability is probably a sticking point with you and causes you some heart ache, I suspect.
    • The template editor is LONG overdue for a remake. WE should all push for this.
    • Many of the concepts in templates probably should be re imagined.  For example, display rules are a plague on mankind.  There should be a better way to develop such logical alternatives and to retrace the logic later. We should push for this.

    Robert Garrett
    Senior Consultant

    www.envisioncad.com

  • 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:

    • Mass-sync templates to the library in a DGN
    • Mass-corridor reattach corridors to new alignments, or previously deleted and reconstructed ones
    • Ability for dynamic cross-section to take dimensions from features/points across corridors, not just in the corridor being analyzed
    • Automatic check-out of template library when opening the library via a workspace on ProjectWise, and a warning that tells you that the version is read-only when applicable

    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.

Reply
  • 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:

    • Mass-sync templates to the library in a DGN
    • Mass-corridor reattach corridors to new alignments, or previously deleted and reconstructed ones
    • Ability for dynamic cross-section to take dimensions from features/points across corridors, not just in the corridor being analyzed
    • Automatic check-out of template library when opening the library via a workspace on ProjectWise, and a warning that tells you that the version is read-only when applicable

    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.

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