© 2009 Bentley Systems, Incorporated Chuck Lawson GEOPAK Product Engineer Abutment Design with Roadway Designer

© 2009 Bentley Systems, Incorporated 2 | Abutment Design Designing a bridge abutment in Roadway Designer takes advantage of the Corridor concept. With the ultimate flexibility of Components and Templates, the Designer can easily conform to any required bridge structure specification. There are many techniques in Roadway Designer that can be used to model bridge abutments. This presentation will cover the workflow used to model a skewed bridge abutment. This method will ultimately work for most bridge abutment types. 2

© 2009 Bentley Systems, Incorporated 3 | Project Review 3 Before we begin, let’s review our project data and the templates that we’ll be using. Plan View Layout

© 2009 Bentley Systems, Incorporated 4 | Project Review Earth Only Slopes at Beginning of Transitions 4

© 2009 Bentley Systems, Incorporated 5 | Project Review Transition Slope  Fill To Structure 5

© 2009 Bentley Systems, Incorporated 6 | Project Review Structure Slope 6

© 2009 Bentley Systems, Incorporated 7 | 7 Project Review Demo

© 2009 Bentley Systems, Incorporated 8 | Creating the Abutment Alignment The first step in the process is to create a horizontal alignment for the abutment corridor to follow. 8

© 2009 Bentley Systems, Incorporated 9 | Creating the Abutment Alignment Demo 9

© 2009 Bentley Systems, Incorporated 10 | Creating the Surface In order to generate a profile for our abutment corridor, we must first generate a surface along our main roadway corridor (US 301). This proposed DTM surface, should ignore the bridge structure completely. This surface will allow the Designer to extract a profile along the abutment alignment stored in the previous step. 10

© 2009 Bentley Systems, Incorporated 11 | Creating the Surface Demo 11

© 2009 Bentley Systems, Incorporated 12 | Creating the Proposed Profile 12 The proposed profile can be created through extracting the vertical information from the proposed US 301 surface. Offsetting the proposed extracted profile by a distance of -0.01’ will allow us to use Target Aliasing and Clipping to generate a very clean cut along the bridge abutment alignment. Once the profile is created, the alignment and profile need to be imported within Corridor Modeler so they are available inside of Roadway Designer.

© 2009 Bentley Systems, Incorporated 13 | Creating the Proposed Profile Demo 13

© 2009 Bentley Systems, Incorporated 14 | Creating the Proposed Corridor 14 The abutment corridor can now be created using the proposed alignment and profile generated in the previous steps.

© 2009 Bentley Systems, Incorporated 15 | Creating the Proposed Corridor Demo 15

© 2009 Bentley Systems, Incorporated 16 | Bridge Omission from Mainline Corridor 16 The bridge template can now be inserted into the mainline corridor. Assuming the bridge is to be modeled separately, the Designer may use a “blank” template for the bridge. If the User wishes to model the bridge within Roadway Designer, then replace the blank template with the actual bridge template. A separate bridge corridor may be the more desirable approach. The best approach for modeling the bridge is to use a Bentley Product dedicated for bridge modeling such as LEAP for example.

© 2009 Bentley Systems, Incorporated 17 | Bridge Omission from Mainline Demo 17

© 2009 Bentley Systems, Incorporated 18 | Abutment Template Design 18 Templates through an abutment may have many requirements based on the bridge design. In this example, 3 templates are used –Template 1  2:1 Earth slopes only –Template 2  Combination 2:1 earth slopes with upper concrete structure –Template 3  All concrete structure

© 2009 Bentley Systems, Incorporated 19 | Abutment Template Design Demo 19

© 2009 Bentley Systems, Incorporated 20 | Template Drops 20 Template drop locations, transitions, and intervals are key to the success of modeling a bridge abutment –Use recommended 2’ intervals everywhere except the filet radii –Use recommended 0.2’ intervals in the filets –Use template transitions to change from earth slopes to concrete slopes

© 2009 Bentley Systems, Incorporated 21 | Template Drops Demo 21

© 2009 Bentley Systems, Incorporated 22 | Target Aliasing Other Surfaces 22 Target Aliasing can be used to target surfaces other than the existing ground surface. The target priorities may be set to choose which surface would have the highest priority.

© 2009 Bentley Systems, Incorporated 23 | Target Aliasing Other Surfaces Demo 23

© 2009 Bentley Systems, Incorporated 24 | Point Controls – Connecting Corridors 24 Point controls can be used to connect points from one corridor to another. This is extremely powerful in enabling a user to focus on one corridor at a time.

© 2009 Bentley Systems, Incorporated 25 | Point Controls Connecting Corridors Demo 25

© 2009 Bentley Systems, Incorporated 26 | Building the Combined DTM 26 Target Aliasing allows the user to take advantage of clipping options when building combined DTM surfaces. The user may choose to clip only the end conditions, or to clip all intersecting components. Clipping the surfaces “on the fly” produces a combined accurate 3D model. This is a very powerful feature of Roadway Designer.

© 2009 Bentley Systems, Incorporated 27 | Building the Combined DTM Demo 27

© 2009 Bentley Systems, Incorporated Chuck Lawson GEOPAK Product Engineer Abutment Design with Roadway Designer