transCAD简单教程

一、概况

TransCAD系统是由美国Caliper公司开发的交通GIS软件，现已推出用于Windows平台的3.5版。

二、技术特性

TransCAD软件把地理信息技术和交通规划技术较好地结合在一起，可以方便地对各类交通运输及相关数据进行存储、提取、分析和可视化。由于采用先进的Windows环境及一系列最新的开发方法，使得软件具有较好的风格：先进的菜单界面、强大的图形功能、方便的工具栏、良好的开放性、多文档、多用户操作等等。

TransCAD与其它Windows应用程序相仿，对容量没有硬性限制，最大限度地发挥硬件能力。运行环境为Windows 3.1及以上版本。TransCAD 3.5为32位应用程序。

三、功能特性

TransCAD主要包括5大功能：

?Windows下的、功能强大的地理信息系统；

?扩展数据模型，提供显示和处理交通数据的基本工具；

?汇集了极其丰富的交通分析过程；

?各式各样、数量巨大的交通、地理、人口统计数据；

?可以生成宏、嵌入、服务器应用及其他用户程序。

交通过程主要包括：

?网络和路径：生成、设置、路段方向、选定路段、转向工具箱、最短路、多路径、货郎担问题、网络分割、带宽设定等

?线路系统：线路服务、站点服务、线路编辑等

?规划：出行产生、吸引、平衡、快速反应模型、出行分布、交通分配等

?公交：网络生成、设置、最短路、网络阻抗计算等

?路线和逻辑分析：成本矩阵计算、货运路线计算与显示、弧最短路、指派问题、运输问题、货流配送、最小成本流、分区、聚类、设施定位等

统计：报表、校正、模型估计、模型应用、生成模型文件、邻接矩阵、空间校准等TRANSCAD教程1-- Project and TransCAD Overview

ORGANIZATION

LAB OBJECTIVES

To provide hands-on experience with transport planning, analysis, and design and t o present Geographical Information Systems (GIS) fundamentals.

TERM PROJECT

Homework assignments and the course project will utilize TransCAD, a PC-based GIS for transportation which is installed in the Civil Engineering Computer Lab in E G3141. A formal lab will be held every week; typically on Fridays but occasionally on Mondays and Wednesdays (a discussion section often may be held as part of t he lab). Individual copies of TransCAD are not available, but additional formal lab ti me will be scheduled as needed. TransCAD manuals will be available in the Lab, and may be checked out from the TA or the main CEE office. The course project will be completed individually (or perhaps in teams of 2). There will be intermediate reports due during the quarter, and a comprehensive final report will be due durin g exam week (tentatively, June 16, 2004). Incorporated into the final report will be one or more network design solutions. It is highly recommended that each person/t eam keep all project material in a 3-ring binder to facilitate management of project

documentation. All project reports must be prepared professionally. Given the import ance of technical writing in the Civil Engineering profession, each submitted project will receive two equally weighted grades: one for technical content, one for report quality. Formal report preparation guidelines are included in the course notes. Sam ple projects from prior years are available from the instructor or TA.

LAB REFERENCES

?Caliper (1996) TransCAD User's Guide Version 4.0

?Additional material focusing on GIS will be available in the lab or on-line.

?Project Report Style Guide

GRADING

Lab works will account for 35% (30% on term project and 5% on unannounced qui zzes in lab) of the total course grade.

SCHEDULE

See Overall Course Schedule

INTRODUCTION

What is TransCAD?

TransCAD is a full-featured Geographic Information System (GIS) designed specific ally for managing analyzing, and presenting data related to transportation systems and facilities. It contains a comprehensive set of transportation analysis models that are commonly used by transportation professionals in their daily work.

What is a GIS?

Different definitions of a GIS have been used in different disciplines. For the newco mers to GIS, consider this relatively simpler definition: A computer software designe

d to manag

e and display data that describe features on the Earth's surface. Examp les o

f such features with transportation relevance are: freeways, streets, bus routes, intersections, bus stops, etc.

Why GIS for transportation system analysis?

GIS make it possible to display and visualize phenomenon such as traffic. For exa mple, GIS can display on a map streets with various widths to represent different amount of traffic on these streets. In addition, GIS can be used to prepare data fo r analysis in ways not possible with traditional transportation modeling software.

Fundamentals of GIS

To be able to use TransCAD efficiently, it is necessary to understand some funda mentals of GIS. Two of the most important GIS concepts are introduced here to fa cilitate the understanding of the tutorial materials. More GIS concepts will be introd uced throughout the quarter.

?Maps are generated from a database

Although GIS display maps, in most cases these maps are not stored in co mputers as image files. Maps are generated by GIS from a database with

different tables. For example, each node in the map (Figure 1) is generated

based on the coordinates in the Nodes table (on the upper right hand sid

e). Each street link is generated by linking the two end nodes (see the Hig

hways/Streets table).

?Features are organized into layers

A map can be regarded as a set of overlaying transparencies. Each transp

arency is drawn with one type of feature. For example, in Figure 1, the ma p consists of two layers: Nodes and Highways/Streets. Each layer is associ

ated with a data table and each feature is linked to a record in the table.

TransCAD Tutorial

See page 15 to 23 of the TransCAD User's Guide

Figure 1 Map and Database

The Miasma Beach Transportation Model

There are six Traffic Analysis Zones (TAZs) in Miasma Beach, and two external stations. Zones 1 and 2 are in the Central Business District (CBD), zone 3 is an urban residenTI Al area neighboring zone 4, zone 4 is a major commercial and industrial area about two miles east of the CBD, and zones 5 and 6 are suburban residential zones located about fi ve miles east of the CBD. Zones 7 and 8 are External Stations representing the eastern a nd western extremes of Coast Highway, the arterial which traverses the southern border of the City along the beach.

The initial transportation network for the city comprises a grid of secondary-classified maj or arterials and a single primary arterial (Coast Highway). The six TAZs are attached by single 0.25 mile centroid connectors. Facility operating characteristics are detailed in Table 1.

+---------------------------------------------------------------+

| ^^^ ^^^ ^^^ Miasma Mountains ^^^ ^^^ ^^^ |

+ N |

| 1st 2nd 3rd 4th 5th W+E |

| Str Str Str Str Str S |

| |

+ 1-+----+-------+---------------+----+-5 Mountain |

| | | | Avenue |

| CBD |1 mi | 4 Urb.Res. | |

| | | | | Suburbs |

+ 2-+----+-------+---+---+-------+-------+----+-6 Miasma |

| | | | Blvd |

| |1 mi 3-+ Comm/Ind | |

| | | | |

+ 8----+---------------+---------------+----7 Coast |

| 0.5 2.0 2 mi 0.5 Highway |

| |

| Ext.Station Ocean Beaches Ext.Station |

+ |

+---+-------+-------+-------+-------+-------+-------+-------+---+

Figure 1. City of Miasma Beach Network Schematic [Spring 2004]

Table 1. Miasma Beach Speed-Capacity Table

-----------------------------------------------------------------

Link Type Speed Lanes Capacity/Lane -----------------------------------------------------------------

1. Freeway 60 2 1800

3. Primary Arterial 45 2 900

4. Secondary Arterial 30 1 600

5. Local Street 15 1 300

8. Ramp 30 1 600

9. Centroid Connector 25 9 1000

Task 1. VALIDATE 2004 BASE YEAR NETWORK

You are provided with two sets of TransCAD files, mb2004.*and Taz.*. The first, mb2004, contains the GIS layer of the coded transportation network; the second, T

az, contains the Traffic Analysis Zones (TAZ) layer and activity system data (demo graphics and trip ends). The first task is to create a map file in TransCAD and to validate the zone system and network structure.

GIS Concepts

Why are there so many files with the same file names, mb2004and Taz?

To efficiently manage information pertaining to a layer, a GIS usually divides the in formation into different files. It takes all the files with the name of mb2004to gene rate the Miasma Beach network in TransCAD. If you want to work from a different directory or computer, you must copy the entire set of files.

1.1 Create Base Miasma Map

Construct the TransCAD "map" file which contains the GIS data for the Base Year 2004 Transportation System T and the Activity System A.

1.1.1Open a Geographic File

Go to File / Open. On the File Open dialog box, select the drive and directory wh ere you store your files (mb2004.*and Taz.*). Select Geographic File under the L ist Files of Type. You should see MB2004.DBD and TAZ.DBD in the file box. Sel ect MB2004.DBD and click OK.

You should now see a "stick" network in front of you. The network does not contai n end points and intersecting points. To see them, go to Map / Layers. On the La yers dialog box, under Layers in Order of Display, select Nodes(it is hidden no w) and click the Show Layer button. Close this dialog box.

Exercises:

?Change color and style of the streets

?Hide streets

?Label each street with ITS name (Hint: All you need is the Layers dialog B ox)

1.1.2Add Another Layer

Go to Map / Layer again. Click the Add Layer button. On the File Open box, op en the Geographic File of TAZ.DBD. You should now see the TAZ layer being add ed to your map but some parts of the TAZ layer seem to be displayed outside of the window. Go to Map / Scale. On the Map Scale dialog box, select Show the E ntire Layer of TAZ and Selection Set All Features.

GIS Concepts

Working Layer (or Current Layer)

When you have more than one layers in your map, there is always one layer desi gnated as the Working Layer(or Current Layer). All the manipulations on the ma p (such as labeling or querying) apply to the working layer only.

Exercises:

?Ask TransCAD to draw TAZs before the Highway/Streets network.

(Hint: Move Up and Move Down in the Layers dialog Box) ?Ask TransCAD to drop the streets from the map and add it back again (Hint: Drop Layer and Add Layer in the Layers dialog Box) ?Label each TAZ with its ID and street with its name

(Hint: switch the Working Layer between Highways/Streets and TAZ and lab el each layer)

Examine the Map

Examine the map and compare it with Figure 1. Familiarize yourself with this map and the characteristics of the various link, node, and zone attributes.

1.1.3Save the Map

After you set up the display of the map to the way you want (which should be lab eled properly), go to File / Save As. On the Save As dialog Box, select the drive and directory where you store your files. Select Map File under the List Files of Type. Type in MB2004under File Name for your map and click OK.

GIS Concepts

What is a *.map file?

A *.map file contains information about the settings of the map such as, what layers are in the map, the color and style of each layer, texts, labels, and freehand items (markers) on top of the map, and the scale of the map. It is important to know that the *.map file itself does not contain databases of the layers. It only tells TransCAD where are the dat abases and how to display them. Without the geographic files, the map file alone can not generate maps.

1.2 Network Updates

Select Highways/Streets as the Working Layer. Implement all network changes identified b elow. Adjust the attributes for all links accordingly.

1.Delete the section of Miasma Boulevard between 3rd and 4th Streets (over the Mi

asma wetlands)

2.Delete the section of 2nd Street between Miasma Blvd. and Mountain Avenue.

3.Add a section of 4th Street between Coast Highway and Miasma Blvd.

4.Add a section of 3rd Street between Miasma Blvd. and Mountain Avenue.

5.Due to recent development changes, the centroid of Zone 3 along with its connect

or have changed. Change the connector so that it connects with Coast Highway in

stead of 3rd St. It should meet the highway 1.5 miles from 1st St and 1.5 mile f rom 4th St.

6.All Miasma network links are secondary arterials with the exception of:

a.Mountain Ave from node 310 to 345 is a local street

b.3rd Street from Coast Highway to Miasma Blvd. is a local street

c.The entire length of Coast Highway is a primary arterial

1.2.1Delete Links

To delete a link, go to Tools / Map Editing. The Map Editing tool box will show up. Press down the Delete button and click at the link that is supposed to be deleted (see (1) in the description above). The color of the link would change and you should see the R ed Light and Green Light buttons appear in the Map Editing tool box. Carefully examin e if you click at the link that is supposed to be deleted, if you click at the wrong link, c lick the Red light button. The change will not be saved. If you are sure that you have th e right one, click the Green Light button. The change will be saved and you should see t he link being removed from the map.

1.2.2Add Links

To add a section of 4th Street between Coast Highway and Miasma Blvd, first click on t he Configure Settings button. Click on Update under the "Join/Split Attribute Settings." Change the "Choosen Options" to Copy for both joining and splitting for every field. Clic k on the midpoint of Coast Hwy between 3rd and 5th. This should split this segment to t

wo 1 mile stretches. Click on the info tool (i.e. the i button in the Tools box) and click on Coast Hwy between 3rd and 4th. Change H_DIST from 2.00 to 1.00. Do the same e

diting for Coast Hwy between 4th and 5th. Press down the Add Line in Map Editing bo x and add a line from the intersection of 4th & Miasma Blvd to Coast Hwy (i.e., single click at the intersection of 4th and Miasma Blvd, drag the dash line straight to Coast Hw y, then double click when the line meets the splitting point). Click on the new line and f ill in each field the same value as that of 5th street, since they have the same length and

are both secondary arterial. Follow the same procedure to add a section of 3rd Street bet ween Coast Highway and Miasma Blvd.

.2.3Move Centroid

To change the centroid location, first delete the centroid connector between the node of c entroid 3 and 3rd St. Press down the Join Line button and click on both links of 3rd St to join them into one. Ensure that the H_DIST of this combined link is 1.00. Using the same process as before, split the section of Coast Highway between 1st St and 3rd St. T he split should be located about 1.5 miles from 1st and 0.5 miles from 3rd, just below th e location of centroid 4. Then add a line from the split point to about 0.25 miles above t he split. Using the info tool, edit this new line so that it contains the same properties as the other centroid connectors. The new node at the end of this link will be assigned an I

D by TransCAD (ie, 351.) Again using the info tool, change the number of this node to

3. As this node is the centroid, it must be named to correspond with it's zone.

1.2.4Edit Link Attributes

To change attributes of network links, use the info tool and follow the way you edit H_ DIST described above.

1.3 TAZ Updates

The TAZ.* files contain information regarding the traffic analysis zones in Miasma Beach, including demographic data. The zonal information stored in this TransCAD network is i ncomplete, you must fill in a few entries. Set TAZ as your working layer, and open the dataview. For zone 2, change the POP (population) value from 0 to 1550. For zone 5, ch ange the EOTH (other employment) value from 0 to 50, and the ETOT (total employment) from 0 to 150. For Zone 6, change the Household Income from 3800 to 38,000.

GIS Concepts

Editing in a GIS

A GIS usually does not let you undo the editing you do. This is because managing geogr aphic information is more complicated than managing just texts and numbers. To prevent users from changing the database accidentally, most GIS ask for your confirmation (such as the Red light and Green light buttons in TransCAD) before the change is saved. Spatial Query

A GIS let you retrieve information pertaining to a geographic entity on the map. This fun ction is sometimes referred to as Spatial Query. You can use the spatial query tools (suc h as the i button in the Tools box) to review and edit the entity's attribute data.

1.4 Formulate Attributes

After you finish editing the network, you need to calculate the free flow travel time for b oth directions of a street. It is easier to do this task in a Dataview (a table that displays data for the entire layer) than using the info tool, because you are now dealing with all streets, not just some of them. To open the Dataview of the Miasma network, make sure the Highways/Streets is the working layer. Click at the New Dataview button. A data wi ndow will show up. Examine the data. The attributes data shown in Highways/Streets data view should correspond to those in Table 1.

GIS Concepts

Link Direction

In the dataview of the Miasma network, Dir stands for direction and is used to indicate i f the street is one-way of two-way. In Miasma Beach,

Dir link values are all 0 indicating that they are all two-way streets. Therefore, on the re cord (i.e., a row in the dataview) of a street, there are two fields correspond to one attrib ute (e.g., speed, capacity, or number of lanes). While AB_SPEED contains free flow spee d of one direction, BA_SPEED contains that of the opposite direction. This could be usef ul, for example, when each direction has different speed limit or capacity. To know which

direction is AB and which is BA, you need to know the direction in which TransCAD draws this link. Look at the following example.

Link 25 contains two end nodes, Node 310 and 320. If this link is drawn from 310 to 3 20, then Arrow 1 is AB and Arrow 2 is BA.

Node 310 +------------------+ Node 320

Link 25

Arrow 1 ------------------->

Arrow 2 <-------------------

The direction a GIS draws a link is referred to as the topological direction of this link. This information exists internally in the database (e.g., somewhere in the MB2 001 files). If you want to see a link's topological direction in Dataview, set Highwa ys/Streets as the working layer and go to Dataview / Formulate Fields. On the F ormula (Dataview: Highways / Streets)dialog box, click at the Node Fields butto n. Another dialog box Node Formula Fields come up. Highlight ID under Choose one or more node fields and select "From" and "To"under Option. Click OK. You should see two fields, [From ID]and [To ID]being add to the dataview. [Fro m ID] is ID of the node from which the link begins and [To ID] is ID of the ending node.

Exercises:

How do you designate a link as a one way street? (Hint: 1 or -1 in Dir)

To calculate the free flow speed for all the streets in the Miasma network, first go to Dataview / Modify Table. Click on Add Field button. Enter the followings under Field Information:

1. Name: AB_TRAVEL_TIME

2. Type: Real Number

3. Width: 10

4. Decimals: 2

5. Uncheck the box in front of Index

Click the Add Field button again. Enter the following:

1. Name: BA_TRAVEL_TIME

2. Type: Real Number

3. Width: 10

4. Decimals: 2

5. Uncheck the box in front of Index

6. Click OK.

You should now see two empty fields AB_TRAVEL_TIME and BA_TRAVEL_TIME being added to the dataview. Highlight AB_TRAVEL_TIME by clicking at its column heading. Go to Edit / Fill... . On the Fill dialog box, select option Formula. On t he Formula Box, build the following formula:

(H_DIST / AB_SPEED) * 60

Click OK on both the Formula and the Fill boxes. Note the values being filled in t he AB_TRAVEL_TIME field. Pick a few links and verify that the values are correct. Repeat the same procedure for BA_TRAVEL_TIME with the formula:

(H_DIST / BA_SPEED) * 60

1.5 Enhance Miasma Map

1.5.1Select Color Themes

With the Highway/Streets layer active, follow TransCAD instructions (pg. 149-158) f or establishing the following link color themes:

1. Freeway = Red 6. Local Street = Light Blue

3. Primary Artl = Green 8. Freeway Ramp = Purple

4. Secondary Artl = Blue 9. Cntrd Connector = Yellow Select line styles which will also distinguish link types.

1.5.2Create Layout

Follow TransCAD instructions (pg. 34-36) to create a layout combining maps and d ata views. Attach appropriate legends and other enhancements.

1.6 Print Miasma Map

After you have verified that your network is correct, print the final map layers and generate reports documenting all data for inclusion in the interim report.

1.7 Prepare Task 1 Documentation

Prepare Task 1 documentation, including all TransCAD maps and dataviews. Follow all Project Report Style Guidelines in the preparation of this documentation. This material will be submitted as part of the first Interim Report(see Task 3).

The Miasma Beach Transportation Model

Task 2. DEVELOP 2004 BASE YEAR TransCAD NETWORK and SKIMS

The objective of this task is to create a TransCAD network file that will convert the GIS information that represents the Transportation System T into a form suitable for subseque nt transportation analysis. The first such analysis task will be to use TransCAD to find m

inimum path trees for all Miasma Beach centroids (internal zones and exterrnal stations).

2.1 Create TransCAD Network File

Set the Highway/Streets layer as the Working Layer. If you don't see Networks/Paths in your menu bar (on top of the TransCAD window), go to Procedures and check it. If you can see it, go to Networks/Paths / Create... . Create links from: Entire line layer. Rea d length from H_DIST, and choose all link attributes under Optional fields(highlight all fields by clicking on the first field and the last field, while holding the "Shift" key on t he keyboard). Save this file as https://www.360docs.net/doc/1a4093255.html,.

2.2 Develop 2004 Base Year SKIM Trees with TransCAD

Three steps are required. First, the actual Interzonal minimum paths are computed. Intrazo nal travel times cannot be computed directly from the network, thus, a second step involv es approximating these times from interzonal times to neighboring zones. Finally, terminal times are optionally appended to selected zone pairs.

Produce a minimum tree schematic for at least one centroid. These schematics will help i dentify any network errors; if any are found, correct them immediately (and repeat earlier tasks as necessary). A sample network tree is in Figure 2.

+---------------------------------------------------------------+

| ----- link is on minimum path tree N |

+ ..... link is NOT on minimum path tree W+E |

| S |

| |

| |

+ 1-+----+ . . . + . . . . . . . +----+-5 |

| | . | |

| | 4 . | |

| | | . | |

+ 2-+----+-------+---+ . + + . . . +----+-6 |

| | . | | |

| | 3 . | | |

| +-+ | | . | | |

+ |8|---+-----------+---+-------+-------+----7 |

| +-+ |

| |

+-------+-------+-------+-------+-------+-------+-------+-------+

Figure 2. Minimum Path Tree for Centroid #8

2.2.1Create Interzonal Skim Trees

Select network centroids to skim and compute shortest path trees.

Select centroids

Set Nodes as the Working Layer. Go to Tools / Selection. Add a selection set by clickin g at the "+" button, then click the "Selection Settings" button. Select your new selection, then click on Remane...Enter Centroids as the new name of this selection. Then, click a t the "Select by Pointing" button on the vertical tool box (the one on the right hand side of the window). You then can click on each of the centroids while pressing down the S hift key on your keyboard (selected nodes will be highlighted).

Find Skim Tree

Make sure Nodes is the Working Layer and https://www.360docs.net/doc/1a4093255.html, is the active network. Go to Ne tworks/Paths / Multiple Paths. Minimize: Travel Time. From: Centroids. To: Centroids. Select Matrix File as an output option (total cost of each path is stored in a matrix file). Click OK and save resultant file as time.mtx.

2.2.2Append Intrazonal Impedances

Compute the average travel time to the two zones nearest in skim time to the zone in qu

estion. Use one half this average as the intrazonal time (diagonal elements). Manually ente r these numbers into the diagonal cells of the matrix created in 2.2.1.

2.2.3Update Skim Trees with Terminal Times

Once you finish step 2.2.2, you have a matrix of Shortest Path with values in the diagon al cells. In this task, you are going to add 1 minute "terminal time" to each interzonal (o ff-diagonal) element. To do this, Go to File / New / Matrix file and click OK. Fill name as Terminal time, IDs are in ID, Rows from centroids, Columns from centroids, then click OK. Save the file as terminal.mtx. A matrix window will appear. Go to Matrix / Fill. In the subsequent dialog box, open the "Single Value" tab, and fill in the following:

Go to Matrix / Fill again. This time fill the following under the "Single Value" tab:

Go to File / New / Matrix file and click OK. Name this new matrix Skimtree.mtx. IDs are in ID, and both rows and colums are from Centroids. Label this matrix Skim tree. Return to Matrix / Fill. This time click onto the "Cell by Cell" tab. Fill the following: