Motivation #

Utility (Gravity and Pressure Pipe Networks) integration between MiTS and Civil 3D involves transferring the civil object’s (pipe and structure) information. In this process, the data exchange needs to be accurate so that the geometries of identical objects are mirrored in both programs.

While this may seem easy with the networks’ mapping features in MCIntegrator, in actuality, moving this data may pose a challenge.

Due to the differences in how MiTS and Civil 3D are built, each program handles utility objects differently, particularly in terms of dimensions and properties, which can lead to inaccuracies, errors, or data loss. To reduce the inaccuracies or errors to as little as possible, we have developed an algorithm with one goal in mind: Data Integrity and Design Continuity.

It is definitely beneficial for users to understand the algorithm for a smooth and error-free integration between MiTS and Civil 3D.

Utility object’s position in 3D Space #

An object position in a 3D Space is determined by the Horizontal Coordinates (XY coordinates) and the Vertical Coordinates – Invert Levels (pipes/drains) and Ground Level (nodes) in MiTS and Start/End Invert Elevations (pipes) and Insertion Rim Elevation (structures) in Civil 3D.

While the properties may “sound” somewhat similar in both programs, the way each program handles these coordinates to build a network system is very different.

In MiTS, the utility network built has been simplified to a collection of coordinates input (X, Y, and Invert Levels) by users, while in Civil 3D, the network is structured by two core geometric parameters: Centerline (for pipe) and Center Point (for structure) that govern the Invert Elevations parameters.

Centerline and Center Point in Civil 3D #

The Centerline of a pipe defines the path of a network in the XY plane, which provides the pipe with its shape, length, and direction. It can be considered as a “frame” and will need the vertical coordinates (in this case, the Invert Elevations) to realistically represent the gradient along the networks.

Then, the centerline of a pipe will be connected to the Center Point of a structure, such as manholes or sumps – a single point at the center that defines the Easting and Northing of the structure, forming continuity in the network

Therefore, to form an accurate network representation in Civil 3D, it is a must for the centerline and center point to work hand-in-hand, which indicates that the integration must preserve these two core parameters during the back-and-forth between MiTS and Civil 3D.

When data transfer is occurring between the two programs, the algorithm should ensure the horizontal and vertical coordinates in MiTS are applied accurately to the centerlines and center points in Civil 3D for data preservation.

How do we preserve the horizontal and vertical coordinates? #

Horizontal (XY) Coordinates #

In all cases, the horizontal coordinates in both programs should ALWAYS be preserved; This is one of the top priorities of the algorithm.

The XY preservation is achieved by ensuring the Civil 3D structures’ center points are equivalent to the MiTS nodes’ XY Coordinates.

To do so, the algorithm must ensure the structures’ connections are always set to the adjacent pipes’ centerlines. A disconnection may trigger a potential issue with the coordinates and would likely cause the structures to be floating in the 3D Space.

How do we check a structure’s connection? #

Select or click any structure in the network > Click on Structure Properties > Go to Connections tab > The connected pipes will be listed as in the image below.

Vertical (Invert Levels) Coordinates #

Preservation of the invert levels is also a primary concern for the integration of the utility networks between MiTS and Civil 3D. The invert level is the key parameter in MiTS that controls the network’s gradient in the 3D Space, which needs to be accurately translated and applied to the Civil 3D pipe’s centerline.

Whenever possible, it is a must to ensure the pipe sizes in MiTS are preserved or equivalent to the mapped Civil 3D Family Parts – the reason why we emphasize ensuring the Part List mapped to the network has the necessary sizes to be employed in a network.

Equivalent sizes will ensure MiTS invert levels are preserved as center lines in Civil 3D, and vice versa.

How to tell whether MiTS and Civil 3D entities are equivalent? #

For a structure or pipe, its equivalence in the two programs is based on the diameter properties (inner and outer diameter), hence why users are required to define the diameter options for the gravity and pressure networks mapping.

The algorithm is built to be “selective” when it comes to synchronizing MiTS’ entities to Civil 3D, such that it will go through the entities listed in the Part Lists employed and choose an item with a matching diameter.

For example,

MiTS pipe: Inner diameter 300mm + thickness 50mm; Outer diameter 350mm

Civil 3D gravity pipes: Inner diameter 300mm + thickness 27.5mm; Outer diameter 327.5mm

When we “sync” the pipe from MiTS to Civil 3D based on inner diameter, the decisive properties will be inner diameter 300mm in the example above, when it comes to selecting the equivalent entity in Civil 3D. (The outer diameter will be ignored during the selection)

Therefore, the sync will be successful, despite the entities having different outer diameters in the two programs (highlighted in yellow). The algorithm will focus on finding the first match diameter and not an exact unique match (all properties are equivalent).

Note:

This is why it is advisable not to change the synchronization strategy halfway. Either you choose Inner Dimension, or Outer, but not switching from one strategy to another. This is to avoid confusion later on.

Guides on checking the diameter properties #

It should be noted that the gravity and pressure parts may have different diameter properties available. Hence, users need to double-check the properties of the entities listed under the Part Lists.

Gravity Pipe Networks #

Pipes

• Checking will be based on the inner diameter for circular pipe, or inner length and inner width for box pipes

• It should be noted that the best option for gravity pipes is the inner dimension, as gravity pipes often lack outer dimension information. In fact, if you choose the outer dimension for synchronization for the pipe, then a verification error will be thrown.

Structures

• Checking can be done based on the inner or outer dimension; If the outer dimension is opted by users, it is a must to ensure the outer dimension is indeed available under the structure properties, or else, the sync is likely to have a verification warning.

Pressure Pipe Networks #

Pipes

• Pressure pipes are typically defined by outer diameter, but you can also choose to define Inner Diameter for synchronization, despite that for some catalogs, the Inner diameter is not defined. In case of this case, the software will be able to compute the Inner Diameter from the Outer Diameter and the thickness, as long as they are available

• The same principle applies if Inner and Outer Diameter swap places in the above paragraph

Fittings and Appurtenances

• It is designed for the algorithm, PressurePartContextType.DiameterNominal to find a matching nominal diameter between MiTS and Civil 3D through iteration. It will start from the smallest size, and if there’s no match or if the information is simply unreadable, it will proceed to the next size available.

• It is also possible for the algorithm to not find a match among the listed fittings or appurtenances, and in this case, the synchronization is possible, but with a warning on the Action Panel.

• For Fitting and Appurtenances, Nominal diameter just means the diameter used in Civil 3D design check, and may not correspond to the actual opening diameter. So if you do take a ruler and measure the actual Fitting opening, it may or may not agree with the nominal diameter.

Do note, the guides and explanations above are only applicable when there is an EQUIVALENT SIZE between the two programs.

What happens if there’s no matching Part Family (Open, cast-in-situ drain)? #

Integration from MiTS to Civil 3D #

In Civil 3D, a network is constructed based on the Part Lists of a network catalog, employed for it.

Hence, it is a MUST for the Parts List to be pre-built with the required Family Parts and sizes, or else, the synchronization from MiTS to Civil 3D will likely fail with a verification error or warning. In other words, the Parts List must already have the Part Size when we try to sync the size over from MiTS to Civil 3D.

You can create your own size for the existing Part Family via the Parts List dialog, but building a new Part Family requires you to navigate the PartBuilder for the model Work Planes and so on, another ‘headache’ to go through.

An interesting scenario, where pipes/drains or nodes in MiTS failed to be synced into Civil 3D because there is no equivalent for the  Civil 3D Part Family, for example, when we try to “sync” MiTS open drains like half round and block drain to Civil 3D, which Civil 3D doesn’t have those concepts at all. In such cases, the suggested workaround is to sync any box-shaped pipes available in the catalog (it must be added to your Part Lists), whereby the open drains are represented in different shapes while the algorithm maintains the horizontal and vertical coordinates.

The algorithm will ensure the MiTS invert levels are preserved by accurately translating the vertical coordinates and applying it to the corresponding box-shaped pipes’ centerlines, in which the sizes may range from the smallest size available to a “matching” size (similar inner diameter).

By having the centerlines equivalent to the MiTS invert levels, it will preserve the vertical coordinates and prevent unwanted changes following the round-trip from Civil 3D to MiTS.

Integration from Civil 3D to MiTS #

MiTS are built with much lesser complexity, no catalog, and no Part Lists to be considered, as the software can create an appropriate entity size on its own without any restrictions for typical pipes or drains.

The biggest challenge in MiTS is only when dealing with cast-in-situ drains that have unique physical shapes, i.e., Block or Half-Round drains. We need to ensure the horizontal and vertical coordinates of the drains are preserved throughout the synchronization. The preservation will require the algorithm to recalculate the invert levels in MiTS in real-time, purely based on the Civil 3D centerlines and existing pipe profile.

This is to ensure that when we have a round-trip sync from MiTS to C3D, no unwanted changes to the centerline or data loss occur, despite differences in the physical shapes of the entities in both programs.

It is also important to take note that changes in the drain size of a unique-shaped open drain, such as Half-Round, or swapping the “equivalent” box pipe diameter in Civil 3D, will not be applied to the network. This is because the main goal here is preservation of the horizontal and vertical coordinates in MiTS through the centerline and center point.