Engineering Applications employing GIS Technology How ArcGIS can be tailored for Engineering and Surveying Applications The following presentation discusses how ArcGIS, ArcMap specifically, was modified to perform civil engineering and surveying applications. Although the presentation is geared for civil engineers and surveyors, there are tools which are presented that are applicable to other disciplines, such as the plan and profile drawing generation. In addition, the approach taken in modifying ArcMap for civil engineering and surveying purposes can be used for other disciplines, such as architecture, environmental engineering and so forth. Presenter: Aaron Norby Kadrmas, Lee & Jackson

Fields Utilizing GIS Business, Telecommunications, Defense, Health, Homeland Security, Education Oil & Gas, and many more… Anyone who has been associated with ESRI for a long time will have noticed that GIS has expanded into a wide variety of areas, and is used for more than just mapping. Analysis has become a “big-time” component of GIS and is one of the reasons GIS has grown so much.

Engineers and Surveyors Even Civil Engineers and Surveyors are using GIS, But not to its full extent. GIS has even been adopted by Civil Engineers and Surveyors, who because of their CAD roots, were slow to get on board the GIS bus. Even so, civil engineers and surveyors are just beginning to use GIS and are not really taking advantage of its full capabilities.

Municipal Clients Civil Engineers and Surveyors working with municipal clients are finding themselves having to supply their clients with data that can be incorporated into the clients’ GIS database Part of the reason for civil engineers and surveyors using GIS is the fact that they deal with municipal clients. Municipalities, as you know, have been using GIS for a number of years. As a result they have developed robust and accurate “enough” databases. This has caused the municipalities to start asking for project data, which the engineers and surveyors have created, in a format that can be incorporated into their GIS. This is a growing trend that is only going to get larger.

CAD to GIS A CAD file (.dxf, .dwg) has typically been used as the mechanism to transfer the engineer or surveyor’s work to the municipal client For now, submitting DXF or DWG files has been the mechanism in which engineers and surveyors have been providing their municipal clients their project work.

CAD to GIS The CAD file (.dxf, .dwg) provides: Exchange of geometric graphics But not a good mechanism for exchanging attribute data Attribute data is becoming more and more important for municipal clients The problem with this type of file is that although most geometric information comes across, valuable attribute or non-graphic information does not easily come across, if at all. This attribute data is very important to the municipality because of the robustness of the municipality’s GIS.

A New Approach Avoid the CAD to GIS transfer by performing the design within the GIS, that is, design with ArcMap ! To address this issue, a new approach is emerging. That is, the utilization of ArcMap to perform design and drafting functions.

Design within ArcGIS By creating custom commands and tools, we can utilize ArcGIS as the graphics engine for performing Civil Engineering and Surveying applications By creating custom commands and tools, we can add civil engineering and surveying functionality that operates within the ArcMap environment.

"drafting as a by-product of the design process" Start to End Approach By creating custom commands and tools, we can utilize ArcGIS to design and draft in a GIS environment "drafting as a by-product of the design process" Now, when we say design within ArcMap, we are not talking about performing one simple task. We are talking about performing an entire project from start to end, from site mapping to contract design document preparation, stakeout, and infrastructure database updating within a GIS environment. Using the fundamental principle that drafting should be a by-product of the design process, the engineer develops almost all of the drawing information as the design process proceeds.

Custom Commands/Tools Visual Basic 6 ArcObjects Avenue Wraps Active X DLL’s } Since ArcGIS provides a developer environment, it is possible for one to develop Active X DLL’s which can be added to ArcMap in the form of custom toolbars. These toolbars will contain the commands and tools providing the civil engineering and surveying functionality. The toolbars shown in this presentation were created using Visual Basic, ArcObjects and Avenue Wraps. Toolbars which can be added to ArcMap, and

Design Processes which can be performed within ArcGIS Survey – Field Work Digital Terrain Model Horizontal Alignments Cross-Sections/Profiles Vertical Alignments Roadway Templates Roadway Surface Earthwork Quantities Subdivision Design P&P Drawings Obviously a civil engineering project involves a number of different tasks. What we will cover in this presentation are the tools which we use for road design and site development. The tasks for this type of work is shown on the slide. To name a few

Topographic Mapping Create a digital model of the project site comprised of contours and existing features utilizing: Aerial photography, and/or Conventional Field Survey Data, better yet Current GIS Database The first task is the creation of the digital terrain model. This model is to contain the existing topographic features of the site, as well as, contours for the site. In this presentation we will discuss how conventional field survey data can be imported. The size, type, location and other factors will dictate the means by which the base topographic map will be prepared. Depending on these means appropriate import formats can be created. Of course the prime, and first source to be looked at is the availability of an appropriate GIS database map. Even if not quite up-to-date, such a base map could serve for a conceptual, preliminary, project design.

Field Survey Data Create a custom command for the mass importing of field survey data in a variety of formats, and with the ability to generate line and curve features from point codes The approach taken, and what will become clear during the presentation, is that for every major task there is a custom command or tool that exists for performing the task. The result of using any of these commands or tools is the generation of point, line, curve, polygon and/or annotation features in as much of an automated fashion so as to minimize the amount of manual editing. For this task we desire to mass import point data from which contours are to be created.

Import Conventional Field Survey Data Here is the Import Points command which allows us to import point data in an ASCII file in a variety of formats. When used in conjunction with point codes, this command is able to generate line work representing the site’s existing features, such as curb lines, building footprints, sewer lines, power lines, and the like. Point codes can also be used to set the symbology for automatic drafting purposes. Within ArcMap the point code is the attribute in which the layer is classified upon. In so doing, the appropriate symbol can be applied based upon the point code. Import Conventional Field Survey Data

Create a custom command for creating contours from: Contouring Create a custom command for creating contours from: Radial survey, and Cross-sectional survey In creating contours, one has to be cognizant of the point data. That is, does the point data represent a radial survey or a cross-sectional type of survey. There are several contouring software that could be used. Many of these prepare superbly looking line work. However, for civil engineering applications, the “exact” (using this word rather loosely) is more important than “nice looking”. Therefore, the ability needs to exist to easily modify a contour line created by automated means.

Radial Survey Data Here is an example of a radial survey, where the surveyor “shoots” points in a radial fashion from some “set-up” or control point.

Cross-Sectional Survey Data Requires special contouring algorithm In the case of a cross-sectional survey, the surveyor takes “shots” left and right of some arbitrary baseline. There is a difference between the two types of surveys because a special contouring algorithm needs to be used when processing cross-sectional types of surveys. Typical contouring algorithms do not handle cross-sectional surveys properly. Requires special contouring algorithm

Contouring Parameters Here you can see some of the contouring parameters that are available for the engineer or surveyor. The top dialog box provides for the introduction of break lines, such as top of bank, or bottom of ditch, where a sharp change in a contour’s direction occurs. The bottom dialog box assists in the introduction of the contour parameters, such as line weight of the heavy contour, contour interval, spacing of contour annotations, contour smoothing, and the like. Contouring Parameters

Stored in a geodatabase are the: Contour strings (polyline features with the elevation stored as an attribute) Elevation annotation Polygons comprising the TIN (3D polygon features) Since we are discussing a new approach in performing design, it is only fitting that the data we create be stored in a geodatabase. In the case of contours, a geodatabase will contain the contour strings, which are actually polylines with the elevation stored as an attribute, the heavy contour elevation annotation features, and the polygons which comprise the TIN. The polygons are actually 3D polygons with each vertex in the polygon assigned an elevation value.

Contours from Cross-Sectional Survey Data Here is a simplistic example of contours created from cross-sectional survey data.

Roadway Design Requires Geometry and Design Data Design Data is assigned an Identifier Custom Commands reference the Design Data Identifier Once the digital terrain model has been established we can proceed with the roadway design phase. The approach taken in performing roadway design is that the user defines the design criteria to be used, identifying each one with an identifier. This identifier is then referenced during the operation of a specific command. The design criteria or “design data” are stored in dBase tables.

Specification of Design Data Since there are different types of design data (the top left combo box menu), there will be different dBase tables containing the different types of design data. Within a dBase table (the bottom right dialog box helps to set the right-of way widths, and the design parameters for the automated design of cul-de-sacs) there could be various design data of the same type, thus creating a library of design data. The design parameter ID is the identifier that the engineer can use to differentiate different design criteria.

Horizontal Alignments An interactive design feature to introduce one or many PI’s with curves and spirals, and dynamically display alignment changes as each PI is dragged across the monitor screen In designing a road, the horizontal alignment is represented as a design feature. This feature can be comprised of one or more PI’s with each PI being assigned interactively a curve radius with or without a back and/or forward spiral length. Control points and their buffer zones that affect the positioning the alignment can be defined by various built-in geometric tools.

Horizontal Alignment with 2 PI’s Here we see a horizontal alignment that is comprised of two PI’s. In this case, each of the PI’s is assigned only a curve radius and no spiral length data. So you can see that a horizontal alignment is more than a polyline, it is a design feature that has been assigned pertinent roadway geometric information. On such an alignment, click at a PI and drag it across the monitor screen. As the PI is dragged the alignment changes reflecting its shape based upon the current location of the cursor. Horizontal Alignment with 2 PI’s

Horizontal Alignment Editing Specialized commands were developed to facilitate the editing, or modification of the horizontal alignments As one understands, the design process is an iterative process, so that, during the roadway layout, the engineer is going to want to alter the design. As such, special or custom tools need to exist to perform editing on the design feature.

Horizontal Alignment Commands and Tools As can be seen a robust suite of commands and tools were developed for editing (dialog box in the low right corner) and post-processing (combo box menu commands in the upper left corner).

Post-Processing Specialized commands were developed to post-process the horizontal alignments so as to facilitate the drafting process (automated generation of lines, curves and annotation features from design data) When we speak of post-processing we are talking about using a design feature in conjunction with design data to mass produce lines, curves and annotation features, with these features being stored in a geodatabase.

Mass generation of features representing the right-of way An example of this is the Generate ROW w/ Cul-de-sac command. Here the engineer specifies the range of horizontal alignments to be processed along with the design parameter ID, from which, the command will create the offset line and curve elements which can represent the right-of-way, pavement ribbon, curb lines etc. The right-of-way design parameter ID contains the design data in terms of offset values and cul-de-sac radii to be used. and the cul-de-sac of one, or many selected alignments with one command execution

Cross-Section/Profiles Using the horizontal alignment existing ground cross-sections and profiles can be extracted from the digital terrain model With the horizontal alignment created, the engineer can proceed to extract existing ground cross-sections and profiles from the previously created TIN, or contours. Note that the TIN could have been created with the 3D Analyst software, if so desired.

Cross-Section/Profile Extraction Again, a custom command is invoked enabling the engineer to specify the horizontal alignment ID along with the other pertinent extraction data. This creates two dBase tables, one for the cross-section and one for the profile. Note that the engineer can extract cross-sections and profiles from contour strings, 3D polygons or a TIN dataset. The result of this operation is the creation of the original ground profile and the original ground cross-sections. There are special commands which enable us to plot the original ground profile and cross-sections. Separate data frames are created to store the profile and cross-sections. Cross-Section/Profile Extraction

Vertical Alignments An interactive design feature to introduce one or many PVI’s with parabolic curves, and dynamically display alignment changes as each PVI is dragged across the monitor screen. With the original ground profile extracted in the previous step we can proceed with the design of the proposed vertical alignment. Similarly to the horizontal alignment, the vertical alignment contains a series of VPI’s with each VPI assigned a station, elevation and vertical curve length. Again, the vertical alignment represents a design feature which we are able to edit and post-process.

Vertical Alignment Design In laying out the proposed ground profile, the engineer superimposes the proposed ground profile upon the existing ground profile. As will be seen later on, the profile will be displayed at the bottom of a sheet, while the top is reserved for the plan view.

Vertical Alignment Editing Specialized commands were developed to facilitate the editing or modification of the vertical alignments Just as with the horizontal alignment design process, the vertical alignment design process is also an iterative process. As such, special or custom tools were developed to perform editing on the design feature.

Vertical Alignment Commands and Tools Here you can see the various commands and tools (upper left corner) that are present for editing and post-processing vertical alignments. The dialog box in the low right corner is for the creation of a vertical curve table that will contain elevation values along the vertical alignment at a user specified range and interval. Vertical Alignment Commands and Tools

Automated Generation of Vertical Alignment Grid and Annotation Emphasizing the “drafting as a by-product of the design process”, the line work and annotation displayed here was all created by the software by invoking a custom command. These features are stored in a geodatabase, and can they be edited by the engineer, if so desired.

Proposed Ground Templates Proposed ground templates (typical sections) are drafted using a custom tool for handling offset distances as well as slope and distance values In generating a proposed ground surface, the engineer creates templates which represent the shape of the proposed ground. To do so a special tool for creating lines given differential offsets and/or slope and distance values needed to be developed.

Typical Proposed Ground Template And its Components The creation of such a special tool really expedites the generation of the proposed ground template because it allows the engineer to define lines given actual engineering parameters. That is, roadway surfaces are typically defined given a slope and distance. As such, the engineer needs a tool that can process slope and distance values. A variety of typical sections can be saved in a library of templates for easy recall.

Proposed Ground Surface Proposed ground surface created by combining: Horizontal Alignment Existing Ground Cross-Sections Vertical Alignment Proposed Ground Templates With all of the roadway components defined, the engineer can begin the process of creating the proposed ground surface. As you can probably surmise, there is a custom command which takes all of the individual components and create a proposed ground surface. This surface is actually a series of proposed ground cross-sections from which a TIN can be created.

Site Contours created from the Proposed Ground Surface Using the proposed ground TIN, we can merge the existing ground and proposed ground TINs to create an overall site TIN, from which, final ground contours can be developed.

Cross-Section Plotting Fully Annotated Cross-Sections are produced by using a custom command which stores the line and annotation features in a geodatabase One of the next steps is to extract cross sections depicting the existing as well as the proposed ground sections. These sections can be mass annotated with a variety of information, and in several formats. If these sections are generated after the earthwork has been processed, the geometric information of the cross sections can be supplemented with those of the quantity takeoff values.

Cross-Section Parameters A combo menu box (upper left corner) contains various commands assisting the engineer to extract cross sections and profiles, and generate earthwork quantities. In the dialog box of the low right corner, the engineer may specify the various annotation parameters that are to be used in the generation of the cross section sheets. Cross-Section Parameters

Cross-Sections with Earthwork Once developed, the various cross sections can be augmented with the introduction such other pertinent information as crossing underground utilities. Note that with all of the features created by these custom commands, the engineer is able to modify any or all as desired.

Subdivision Design A “Block” of land can be subdivided into individual lots by specifying: The four sides comprising the block and The design zoning criteria identifier The subdivision of a parcel of land is controlled by various local planning board and zoning board requirements that dictate the width of a street, the size of a lot, and the positioning of the house within a lot. Designing a two or three lot subdivision Is not a big deal (time wise), or even for a few more houses. For a larger subdivision, however, an automated generation of the lots is a welcomed feature. Complex developments can be broken into blocks, which are then subdivided by the program into zoning conforming lots.

Subdivision Design Data Various subdivision lot data can be stored like roadway design data in a dBase table for easy recall for a particular project. The combo box menu in the upper left corner contains the various subdivision commands, while the bottom dialog box requests the zoning lot requirements. The top dialog box applies the pertinent zoning requirements to a block and subdivides it into lots. Subdivision Design Data

A four sided “Block” and its automatic division into lots conforming to zoning regulations All lots in a block are generated by the program meeting minimum lot areas, set back distances, set back widths, and side and rear lot clearances. A distinction in the these requirements is made between corner and interior lots. Any excess area is then divided among all or user selected lots.

Mass Generation of Lots, Metes & Bounds and House envelopes Once a block has been subdivided, the various lots may be annotated with their metes and bounds, lot number and area in square feet (sm) and acres (ha). In addition, the house envelopes meeting the zoning setback and clearances can also be mass generated.

Plan and Profile Drawings P&P Drawings are created by specifying: A sheet identifier and The components to be included on the drawing, as the plan view, profile view, north arrow, drawing sheet border, etc. One of the final products of the design process is the preparation of the plan and profile sheets, commonly referred to as the P&P sheets. When the design of the horizontal and vertical design processes is done as previously stated, the entire project is designed as a whole in a world coordinate system. It is now time to break down into small (24”x36”) sheets with the plan view at the top, and the profile at the bottom of each sheet.

P&P Drawing Components A menu combo box and a special dialog are employed to cut-up the project into individual sheets and specify the various components that comprise the plan and the profile views of the project. Such components, in addition to the actual plan and profiles, could include mass annotation of existing and proposed ground elevations at a specified station interval, north arrow, sheet title block, and the like. Individual sheets may be augmented by specific details drafted with the various geometric tools. In essence we are creating a dBase table that contains the individual components with pertinent transformation information stored for each component for every sheet to be assembled by the software.

Here is a sample P&P sheet.

data which is pertinent to the municipal client Design Data Exchange During the design, pertinent information can be stored with the drawing features such as: Lot Number House Number Block Number Pipe Length Pipe Material Pipe Size Street Name Design Speed etc. When the design has been completed, the project database contains most of the attributes that a municipality needs for the maintenance of its infrastructure. Field changes during the construction of the project can be introduced to update the design database, and turned over to the municipality for its use. Prior to the commencement of the project, the engineer and the client can discuss what attributes should be incorporated into the database. Afterwards, as the design proceeds the engineer can populate these attributes with the appropriate values with the CEDRA-DataEditor, which is included with the CEDRA-AVland software. data which is pertinent to the municipal client

Integration with the 3D Analyst During the course of the design, the project database can be integrated with the 3D Analyst to assist the engineer in the refinement of the design, and to prepare renderings for public information meetings.

Summary ArcGIS can be used as a graphic engine for design and drafting applications. Performing the design in ArcGIS enables the engineer to provide a more compatible product for incorporation into the municipal client’s GIS. ArcGIS can: Be used as an engineering design graphic engine, and Produce a very compatible product for a municipality’s facility management database (go to next slide)

Summary The fundamental ArcGIS concept of combining data with graphics in one environment provides a path towards the total design process of a project. by attaining the GIS concept of integrating into one entity graphic and information data.