Grading Edits Tips and Tricks

Here are 3 grading tips and tricks i would like to present to you.

1. The fastest way to pull contours from a surface is used the extract objects from surface options. You can find this option under the surface pull down then utilities.

2. The best way to remove brealklines or points from a surface is to go into your surface properties, then select definition tab. From here you can remove objects. It will ask you if you want to rebuild your surface. Select yes. This is where naming your breaklines can come in handy. I try my best to name all my breaklines so it will make it easier on me to remove if have to.

3. You can create featurelines from corridor in two ways. First you can use created featureline from corridor option which is in your home tab, featureline pull down. The second way is to go you corridor pull down, select properties, then create grading featureline from corridor.  You also set your featureline to be dynamically linked to your corridor.

4. Always check your surface data under the surface propertied statistic tab. Here you can see if you have a bust in your elevations by checking your min. and max slopes and elevation.

Importing dgn Files

For those that don’t know how to import a dgn file into autocad or civil 3d the command is dgnimport or dgnattach.  Here are some other helpful information about import dgn files and terms.

Micro station                  AutoCAD

Geometric Elements         Geometric Objects

Levels                             Layers

Cells                                Blocks

Text Elements                  Single-line Text

dgn sheet model               dwg lauouts

styles                               objects, multiline, text ojects

I will get a little more in depth with this tomorrow.

Is using Civil 3D Cost Efficient?

Hi everyone. I'm sorry I haven't posted in a long while. I have been tied up with my C++ programming class lately. So far, it has been fun and interesting. On another note, I have some great news. I am now part of the spectular group of civil 3d guru's on Civil3d.com. So be looking for my first post sometime this week. I will still be posting on here but also definitely check out the Civil3d.com website. On top of that, you can also find a link to my website in the AUGI and AU websites now.

Ok there was a great debate at work this week on how civil 3d can benefit the company and help save time and money on projects. I have heard rumors that some companies have given up on Civil 3d because it did not perform to their expectations and cost them to go over the budget on projects. On top of that, the program has become too difficult to learn and teach. So a few questions came up during our discussion such as at what point in your project do you use the grading feature in your project? Some believe that for the first city submittal  that only polylines should be used to represent contours and no PG surface is built to save time and money. In addition, proposed surface spot shots would be manually typed in. Basically your first submittal would feel and look like it was designed in the old land desktop version. On top of that, should any 3d grading features such grading groups, corridors, and features line be used for small projects? The problem I see with this is the editing time now increased because all the objects are not dynamic. These leaves more room for errors. You will now have to go back and manually edit every mtext or text you typed in. On top of that, a PG surface has to be created in order for storm and sewer structure tops to be tired to. The largest questions that came up wax at what point do you decide if a certain project will or will not use the civil3d grading features? I would like get your feed back on your end on how grading is done for small commercial lots and large subdivision projects? On top of that, has civil 3d saved you money or caused you to increase the cost of projects? What has been the positive and negatives points about Civil 3d?

Pipe Network Vistas

Here is a quick tip for those that need their whole pipe network to reference the right surface,alignment, rendering, or style. I think I may have read this on one the Civil 3D books.

1. Select and right click on any pipe section or structure and select Edit Network .


2. Select the Pipet Nework Vistas button on the network layout dialog box. It's the second to last button
on the far right.

3. The panorama dialog box will appear. Now lets say you need all the pipes to reference the same alignment. Right click on top of the Reference column header for alignments and select Edit.

4. Another box will appear with all the current alignments. Select your alignment and all your pipes will update and point to the alignment you selected.

5. You can also do this with surface, description, style, rule set, render and many more. Remember to do both the pipes and structure tabs.

Storm Pipe Hydraulics Part III

Ok so I finalized my storm pipe profile for pipe running full flow. Now I feel comfortable with what I have. If you notice, I dont show depth of flow because the pipe is running full. The only information I inserted in was the flowrate for each pipe section. Send me a message if you would like help on getting this label styled setup. I'm also working on getting my partial flow pipe label approved by the top dogs at our company where I work. I still want to work a little more on the Storm Sewer Extension 2010.

My next project is corridor intersections and possibly quantity take-offs Keep in touch and thanks for the comments.

C3D 2012 Wish List

1.One thing I really wish 2012 could do is tie a parcel (drainage area) to a storm inlet. If you could pull lets say the area of the parcel associated to an inlet, I could created an expression that would calculate the runoff coefficient for that drainage area. Then somehow tie my pipe section to that expression to calculate my flow rate. This would save me some time so i dont have to plug in the flowrate for each pipe section. Maybe Autodesk will do something like this in the near future.

2. I would also like to see more abilities or functionality for the pipe rules.
3. I wish the description I type in for null structures would not reset when editing inverts
4. Option for staggered pipe profile labels.
5. Ability to just insert hgl data (linework) from storm sewer extension and not update or recreate pipe network.
6. Add a storm design code for minimum  pipe radius and slope per pipe size.

Storm Sewer Extension Notes

For those that are using 2010 storm sewer extension here is some helpful information that I found for different types of design methods.

Analysis w/ Design


After the flows have been computed, this option analyzes and designs starting downstream and working upstream, and uses the existing data for the calculations, such as pipe sizes and invert elevations. Data options that are set to 0, are designed by Hydraflow Storm Sewers Extension. First Hydraflow Storm Sewers Extension calculates the pipe size based on the specified design velocity, (Q/V = A). Next it computes the corresponding invert slope based on Manning's Equation, and with the new pipe area. Based on the settings in the Design Codes, it sets the downstream crown (or invert) equal to the next downstream line's crown (or invert). If the inverts have been set to 0, then Hydraflow Storm Sewers Extension begins at the downstream end of Line 1, sets the crown elevation equal to the starting HG, and proceeds upstream. Hydraflow Storm Sewers Extension does not assign pipe sizes outside the range you specify in the Design Codes.

Enhanced Modeling System

Traditionally, storm sewers are designed to flow full because the pipes are sized to accommodate the design flows and velocities, and there are no conflicting numbers, so the time of concentration (Tc) matches the flow rate (Q).

When analyzing existing systems, the actual velocity is not known until the hydraulic grade line (HGL) is computed. The computed Qs and HGL are based on assumed pipe velocities. When the actual velocity is different from the assumed velocity, the computed Tc is incorrect and the computed Q and HGL are incorrect. Enhanced Modeling System solves the problem by directing Hydraflow Storm Sewers Extension to recompute the hydraulic grade line, based on actual flow rates and actual Tc. Hydraflow Storm Sewers Extension computes three system iterations so that the computed Tc matches what was assumed with reasonable accuracy.

Hydraflow Storm Sewers Extension first computes the HGL using the Tc based on the design velocity. Next it computes the storm sewer system a second time using Tc based on actual velocities. These new velocities are still incorrect because they are based on the original HGL calculation, however they are more accurate than those used on the first trial. Several system iterations cause the Qs, Tcs and resulting HGL to converge to correct values. Three iterations are the most practical balance between accuracy and the time required to produce the results.

Full Design

With this option, Hydraflow Storm Sewers Extension resets all pipe sizes and invert elevations to zero and redesigns the entire system. Pipes are sized first based on the specified minimum/maximum pipe sizes and design velocity. It then computes the invert slopes using Manning's Equation and the computed pipe size. Next it sets the invert elevations as high as possible but always below the minimum cover specified. At junctions, the outlet invert elevation is fixed by the lowest Inlet/Rim elevation. This option requires all lines to have Inlet/Rim elevations.

When selecting pipe sizes, Hydraflow Storm Sewers Extension computes the required area based on the design velocity. All pipe sizes are within the range specified in the Design Codes.

Capacity Only

This option has some design limits. For example, if a pipe size has been set to 0 for design, Hydraflow Storm Sewers Extension cannot size it because it does not know the flow rate, Q. It sets the pipe size equal to the minimum size specified in the Design Codes. Pipe inverts and slopes are set by the same methods as in the other calculation options, using Manning's Equation and the design velocity.