User Friendly Electronic Database Management System for Infrastructure Maintenance in Small Cities Prepared for Institute of Transportation Engineers 2005 District 6 Annual Meeting Kalispell, Montana Prepared by Abhro Mitra DKS Associates 1400 SW Fifth Ave, Suite 500 Portland, OR 97201 Ph: (503) 243-3500 Ext: 249 Fax: (503) 243-1934 E-mail: axm@dksassociates.com
Mitra, A Page 2 of 9 ABSTRACT Traffic sign maintenance is an important aspect of Transportation Infrastructure Management. It is necessary to maintain a log of sign condition records to ensure regular maintenance. For bigger cities it could be a challenging task to manually record and update the status of thousands of traffic signs. Therefore, many states and cities have advanced technologies that help in updating the status of the sign conditions on a periodic basis. However, for smaller cities and local jurisdictions it might not be possible to adopt sophisticated and expensive technologies to maintain an inventory of the system, track its performance and log information for necessary maintenance when needed. Taking this into account, the primary objective of this project was to develop a Sign Database Management System (SDMS) for the city of Sunset, Utah, located in Davis County, north of Salt Lake City. A computerized database management tool using MS Access application and SQL programming was developed. The graphical interface designed for this inventory system is extremely user friendly with plenty of help features requiring minimal training for employees. It is very cost effective and could be used by the city to record information about various traffic signs and log information electronically. INTRODUCTION Maintaining a transportation infrastructure facility is a challenging task which requires a lot of monetary effort. In real world any infrastructure facility is subject to failure when it reaches its threshold. However this threshold time can be increased significantly by ensuring timely system maintenance. A typical maintenance procedure involves several elements. The first and foremost is having an inventory of the system. This procedure can include all or many of the following steps (1): Access previous database to update and record the present condition Record the current system condition Transfer data from a bar code scanner to a maintenance database system Managing all the information For large cities with greater economic potential, it is possible to maintain extensive records of traffic signs but that may not be the case for small local jurisdictions like the City of Sunset. The Pennsylvania Department of Transportation has designed and implemented a statewide sign inventory management system that has been developed using GIS, MS Access Database and Visual Basic programming language (VB) called Sign Inventory Management & Ordering System (SIMOS). This has made the state move a step ahead from the manual system of recording the sign inventory. PennDOT annually installs around 100,000 signs and maintains 1.3 million (source: HTUhttp://www.intergraph.co.ukUTH). Hence it became necessary to have a statewide inventory to record all the information in a single centralized database. The greatest advantage of this system is that it has increased the operational efficiency and improved the sign review cycle time. Oregon Department of Transportation (ODOT) Region 2 initiated an effort in 1994 to develop a sign database for its region using MS Access. The total number of signs were not as many as PennDOT, but the goal was to track the condition of the signs and to have a complete inventory. Oregon also used a Traffic Sign Information Management
)U and Mitra, A Page 3 of 9 System (TSIS) developed in FoxPro (Source: HTUhttp://assetmanagement.transportation.org/tam/aashto.nsf/UTHU)U for some period of time. The Wisconsin Department of Transportation currently uses MS Access database to record traffic sign information, and is currently in the process of converting it to the ORACLE platform to facilitate its integration with other districts. Approximately 300,000 signs have been inventoried in the year 2003 (source: Uhttp://assetmanagement.transportation.org/ have been logged electronically. STUDY AREA This project covered approximately 0.38 sq miles of the city. There is Union Pacific Rail Road line to the west of the study area, highway 91 to the east, 2700N to the north and 2300N to the south. There are two churches, one park and an elementary school. Utah Transit Authority (UTA) bus route 640 runs north-south on limited roads. The area is mainly residential but there are little stretches of small commercial development at the north-east corner along Highway 91. The entire road network within the city is in the form of a grid-iron. OBJECTIVES The primary goal of this project was to develop a Sign Database Management System that would address the city s need to maintain and update its traffic sign database conveniently and efficiently. The main objectives were: Conduct a primary survey to record the traffic sign information Develop a database for the traffic within the study area by gathering information about the sign condition, location, sign type, sheeting type etc. Develop a Sign Database Management System that would assist the city in the future to maintain and update its database electronically Methodology The methodology of this study is primarily divided into three stages as shown in figure 1. In the first stage, all the information that was needed to build a detailed sign inventory was identified. A sign inventory form was designed keeping in mind that the recorded data should capture details about sign location, condition and sign details. The subsequent sections will describe in detail the various factors that are considered for recording sign specific information. In the second stage, a database was constructed using the MS Access program and all the field data that was collected during the previous step was fed into the database. Access was chosen considering the fact that it is very user friendly and easily available. The recorded information was then processed by queries and expressions and a data entry form was created. A form in Access is a user environment that is easy to use and helps in quickly recording inventories like the one used in this study. The intensive form design phase involved several key considerations like usability, visually pleasing graphical user interface, functionality, data validation and plenty of easy to access help features. The SQL query design at this stage enabled the form to be very user friendly. An interface to store data in datasheets and print it in the form of a report was also created as a part of this stage. The strategic design of the forms makes it easy to use even for beginners who are not conversant with Access to use it to record the collected information and store it electronically.
Mitra, A Page 4 of 9 Figure 1: Methodology STAGE: I Survey of existing traffic signs Designing inventory form identifying requirements Overall sign characteristics Specific sign details Maintenance information Is information comprehensive for study objectives? No STAGE: II Yes Creating a database of the inventory in MS Access Create MS Access Form & Report tool for recording sign information Build queries Design Form Link data No Is the tool user friendly? STAGE: III Yes Analyze the data Findings & Conclusions
Mitra, A Page 5 of 9 DEVELOPING USER INTERFACE FOR DATABASE USING MS ACCESS/SQL Considering the fact that City of Sunset was a small city, it was important to develop a convenient and cost effective tool that the city could use to update their traffic sign database time to time. As discussed earlier some DOT s like PennDOT have developed sophisticated and expensive computer programs for similar purposes because of the sheer magnitude of the number of traffic signs that they have to maintain. However such systems are impractical for smaller jurisdictions like City of Sunset that operate within limited budgets. Therefore, it was decided that MS Access and SQL will be used to develop the interface. MS Access comes standard with any Microsoft Office package. The details of the database that was developed are discussed in greater detail in the subsequent passages. When the application named Sunset_SDMS is loaded it opens up an interface (figure 2) that has various input fields to record different types of traffic sign information. The data entry fields on the interface are divided into the following sections (refer figure 2): 1. General traffic sign information noted in the following recording fields Sign ID Text on Sign Location of Sign Category 2. MUTCD guidelines associated with the sign type 3. Specific sign details noted in the following recording fields Sign Height Sign Dimension Support Type Sign Backing Sheeting Type Sign Position 4. Sign inspection & maintenance information noted in the following recording fields Sign Face Condition Inspection Date Last Inspection Date Comments on Maintenance 5. Sign performance index analysis module Many of the input fields in various sections are accompanied with a help button. Clicking on this button pops open an information bubble containing specific details pertinent to the input field (refer figure 3 to see an example pop-up). If data is not available for any field it could be left empty and the information will not be stored in the database. SQL queries were designed to add more functionality to the form e.g. program the help buttons, drop-down menus for faster and consistent data entry, to calculate the performance index etc.
Mitra, A Page 6 of 9 Figure 2: SDMS User Interface Figure 3 Example showing a pop-up for help button for the sheeting type input field(left) and a drop-down for sign category (right) designed using SQL
Mitra, A Page 7 of 9 Type of Information recorded using the Interface Traffic sign data was collected primarily under three categories, a) sign type and location, b) specific sign information & c) sign maintenance condition. The location data was classified into two categories, one was the location of the sign in terms of its coordinates and the other was the site specific location, for e.g. location of the sign from the curb or the sidewalk. Specific sign information was recorded for the sign height, sign dimension, support type, backing, sheeting of the sign, installation date, condition of the sign. There is also a provision to enter comments about the overall condition of the sign. Sign support type was classified into the following categories that were coded into the interface to pop-up as a drop-down menu (refer similar example in figure 3): Square tube type U Channel type Round tube type Wood support Breakaway design type The square tube, U channel and the round tube are mostly steel poles. Breakaway types are usually not very common due to the cost of the design, but had been included in the survey format. The cross sectional dimensions of these support types vary according to the various standards set by the State DOT. Sign backing information was classified into the following categories that were coded into the interface to pop-up as a drop-down menu (refer similar example in figure 3): Steel: This type of backing is very strong and is resistant to any gunshots. However it is a heavy metal and is very susceptible to rusting. This type of signs backing is used most of the times in rural freeways, park areas etc. Aluminum: This is moderately strong, has a long life and is used for all kinds of traffic signs. Wood: These are large in sizes and are moderately strong. Due to extreme sensitivity to inclement weather conditions, they generally do not last very long. Plastic: This backing is useful around lakes and recreational areas, parking lots etc. they are low in cost and are generally durable. Others: An open category was also kept as an option in the survey format to record any special backing type that was present on the city traffic signs e.g. backing materials like fiber glass. Sign sheeting can be either fluorescent or standard. Depending on the sign type, the sign sheeting is selected. School signs usually have the fluorescent sheeting type. Sheeting type also varies depending on the requirement of the nighttime visibility of the sign. Information about sign-face condition was recorded on a subjective basis under the following criterions: Shiny representing excellent condition Little dirty representing a good condition Somewhat Dull representing a somewhat fair condition Dirty & Faded representing a poor condition Dilapidated representing that the sign needs to be replaced or taken care of
Mitra, A Page 8 of 9 The Rationale for Sign Performance Index (PI) Analysis This module was designed for a quick reference to ascertain the overall condition of a traffic sign that would help the city to prioritize and schedule the maintenance effort. The concept of weighted index was applied to derive a performance index. Four fields were programmed in the interface with a help button below each explaining the module. The fields are: Field 1: Sign Type Weight Field 2: Weight 1 Field 3: Weight 2 Field 4: Weight 3 1) Field 1- Sign Type Weight. A weight of 1 to 5 can be assigned. Highest weight of 5 is given when we have a sign under the regulatory category. Since regulatory signs are the highest priority signs they are given the highest weight. The numbers decrease with the importance of category with 1 being lowest for a guide sign. 2) Field 2- Weight 1 field: This field is based on the sign sheeting type and a weight of 1 to 5 could be assigned. A number of 5 is assigned for ASTM V Sheeting type. Higher the sheeting type the better is its durability. So ASTM 5 is given the highest weight. The numbers decrease with the sheeting quality. 3) Field 3- Weight 2 field: Is based on the sign-face condition with 5 being highest for Shiny-excellent condition. Sign face condition is determined by how shiny it is. So shiny is given highest weight. The numbers decrease with deteriorating sign face condition. 4) Field 4- Weight 3 field: Is based on the overall comments on maintenance. If the sign is in good condition weight of 2 is assigned and if it is bad 1 is assigned. There are no other weight values for this field. The following equation was used to compute the weighted performance index that was programmed as a SQL code within the interface. PI =([Sign Weight]*[Weight 1]+[Sign Weight]*[Weight 2]+[Sign Weight]*[Weight 3])/[Weight 1]+[Weight 2]+[Weight 3] Higher the PI value, the better is the sign condition and so maintenance priority for the sign is low. Although this is a rudimentary method and is not an accurate measure of the performance index of a traffic sign, it can still serve as a good indicator to help the city prioritize the maintenance. A more detailed analysis will result in a normalized assignment of the weights resulting in a better index. SUMMARY & CONCLUSIONS The software inventory system developed as a part of this study is intended to be an easy to use tool that can be an asset for small cities to maintain their database electronically. Such an electronic system using MS Access / SQL is ideal for small jurisdictions that have low budgets for infrastructure maintenance. The method proposed in the paper for evaluating the Performance Index of the sign condition might be very helpful for the city. It also helps in giving an immediate assessment of the sign condition. The graphical interface designed for this inventory system is extremely user friendly with plenty of help features. This eliminates the need for extensive training of employees
Mitra, A Page 9 of 9 cutting costs further. This tool has further scope of development if it can be integrated with a GPS/GIS system. ACKNOWLEDGEMENT The author acknowledges Dr. Wayne Cottrell for his guidance and the City of Sunset Public Works Director Mr. Mickey Hennessee for his co-operation with this effort. The contents of this paper and the views expressed are solely of the author. REFERENCES Vereen, S. C., and Hummer, J. E., Documentation of A Sign Inventory Study to Assess Liability and Cost, Publication FHWA/NC/2002-017, U.S. Department of Transportation, 2002. Kruse, K. B., and Simmer, T., Asset Management of Roadway Signs through Advanced Technology, Upper Great Plains Transportation Institute, North Dakota University. June 2003. Guidelines for Transportation Management Systems Maintenance Concepts and Plans Homepage. HTUhttp://ops.fhwa.dot.gov/Docs/TMSMaintCptandPlans/chapter2.htm#UTH Usection2.5.U Accessed April 19, 2004 Inform Sign Inventory Homepage. HTUhttp://itsdocs.fhwa.dot.gov/inform/p46.htmUTH. Accessed April 26, 2004 Maintenance of Signs and Sign Supports Homepage HTUhttp://safety.fhwa.dot.gov/media/sign_supportUTH. Accessed April 26, 2004 National Handbook Homepage. HTUhttp://www.mackblackwell.org/research/finals/arc9206/Volume2/MBTC9206-2.htmUTH. Accessed April 19, 2004 PennDOT s Homepage. HTUhttp://www.bts.gov/programs/geographic_information_services/reference/gist/2001/13/13 1/index.htmlUTH. Accessed April 26, 2004.