| Chapter | Title | Page | |---------|-------|------| | 1 | Introduction to Subassembly Composer | 3 | | 2 | Interface & Basic Workflow | 7 | | 3 | Building a Simple Shoulder Subassembly | 14 | | 4 | Adding Decision Logic (If/Then) | 22 | | 5 | Target Parameters (Surfaces, Alignments, Profiles) | 29 | | 6 | Debugging, PKT Export & Corridor Testing | 36 |
Before placing geometry, define user-changeable variables in the tab: CurbHeight (Type: Double, Default: 0.150m) CurbWidth (Type: Double, Default: 0.150m) GutterWidth (Type: Double, Default: 0.300m) GutterSlope (Type: Grade, Default: -2.0%) Step 2: Establish the Origin and Gutter
The tab where you define variables (like "Lane Width" or "Pave Depth") that users can change inside Civil 3D. 2. Setting Up Your Parameters
Coding links (e.g., "Pave", "Top", "Datum") is critical. "Top" links form the finished grade surface, while "Datum" links form the earthwork/subgrade surface. 3. Shapes (S) civil 3d subassembly composer tutorial pdf
Finding high-quality Civil 3D Subassembly Composer (SAC) tutorials often means digging through Autodesk University (AU)
Autodesk's official help system is the authoritative source for technical details and workflows.
When you launch Subassembly Composer, you are presented with a five-panel workspace. Understanding these panels is critical to mastering the tool. | Chapter | Title | Page | |---------|-------|------|
Navigate to the tab and define the following variables: Default Value Display Name GutterWidth Gutter Width GutterSlope Gutter Cross Slope CurbHeight Curb Face Height CurbWidth Curb Top Width Step 2: Establish the Origin Point (
The central canvas where you drag and drop elements from the Toolbox. It maps out the logical execution flow of your subassembly from top to bottom. Preview Panel
Select the new point P1 . In Properties, set its Origin to 0, 0 . Assign the code "Top_Curb" . Drag a second P2 under P1 . Set P2 geometry type to Delta X and Delta Y . "Top" links form the finished grade surface, while
While this article covers the basics, mastering SAC requires practice. The following are excellent, free PDF resources for deep-diving:
The Subassembly Composer for Civil 3D is a standalone application that allows designers to build, modify, and manage custom subassemblies without needing to know complex programming languages like .NET or C#.
Before diving into geometry, it is essential to understand the primary panels within the SAC interface:
To progress further, consider saving this documentation as a reference guide. Experimenting with simple geometric variations will build your confidence in deploying advanced visual programming logic across your civil infrastructure infrastructure designs.
Every custom subassembly is built using a geometric hierarchy: : Specific coordinate locations ( ). Every point requires an origin point to measure from.