6.0 DATA SOURCES AND COMPUTATIONAL METHODS FOR AGENCY AND CONTRACTOR WORK ZONE EFFICIENCY AND PRODUCTIVITY PERFORMANCE MEASURES

Methods of tracking work efforts and productivity in the highway construction industry have existed for many years, and have been well integrated into the institutional structures of most agencies and contractors. The primary focus of these efforts has been on ensuring that quality work is being performed efficiently, as well as on providing data that can be used for planning and estimation efforts on future projects. Recently, additional attention has been given to the influence of work productivity and quality upon work zone safety and mobility. Work completed as fast as possible minimizes the exposure of both travelers and work crews to the safety hazards of work zones, and can reduce the total amount of delay and congestion that are attributable to the presence of work zones on a facility. Likewise, construction and maintenance efforts that improve the overall durability of the roadway can reduce the frequency of all types of work zones on the roadway, which also reduces work zone exposure and impacts. Consequently, quantifying both productivity/efficiency and roadway durability and relating them to decisions on construction methods, contracting techniques, and materials used is another important dimension work zone safety and mobility performance measurement.

6.1 Efficiency and Productivity Data Sources

6.1.1 Sources That Already Exist

Existing Sources of Work Zone Productivity and Efficiency Data Construction management system database entries Lane closure request and approval database entries Daily project diary notes

Data collected specifically for a work zone – All agencies maintain some type of electronic construction management system for the various projects being funded. Data from these databases are developed into productivity rates and quantities for various work tasks. These databases are also used to track such things as percent of project funds expended versus amount of work accomplished, percent of projects on time, and so on. Depending on the system, parsing of these data could yield measures that can assess how well a particular strategy to accelerate construction is working. It should be noted that although a construction management database provides an ongoing record of project activity on a section of roadway over time, the duration that such records are kept varies from agency to agency. As a result, it may be necessary to initiate additional data recordkeeping to track such efforts over the long term.

Figure 6-1. Various Construction Performance Metrics are
Computed from an Agency's Construction Management Database
Virginia Department of Transportation

In addition, a construction management database will not include activities that are performed by agency maintenance forces or by utility departments. Some agencies have initiated formal lane closure request and approval processes for certain roadways, regardless of the entity performing the work. Also discussed previously as a source of lane closure exposure data, such data can also be used to assess time between work activities on a roadway segment over time, if all entities performing lane closures have to request permission. An example of such a system that is used by the Illinois Tollway Authority is shown in Figure 6-2 and Figure 6-3.

Figure 6-2. Illinois Tollway Lane Closure Entry Screen
Illinois Tollway Presentation to the NCHRP 20-68A Domestic Scan 08-04 Team.
Columbus, Ohio. March 12, 2010

Figure 6-3. Illinois Tollway Temporary Lane/Shoulder Closure Database
Illinois Tollway Presentation to the NCHRP 20-68A Domestic Scan 08-04 Team.
Columbus, Ohio. March 12, 2010

Information recorded in the daily diary of a project may be another important source of productivity and efficiency data. Hours of certain types of work activities (such as when temporary lane closures are occurring) have been previously discussed as a type of exposure data that can be used to compute other mobility or safety performance metrics (e.g., vehicle-hours of delay per hour of temporary lane closure). However, some of these data can also be used as performance to assess agency or contractor efforts to minimize work zone impacts (e.g., percent of work activity hours that required a temporary lane closure).

6.1.2 Potential Sources in the Near Future

Mobile applications to gather work activity data in the field – Several companies are working on mobile applications to gather work activity directly from field personnel in real time. Although the primary intent of the technology is to improve accuracy of the data entered (many of the applications are based in part on a geographic information system [GIS] platform) and drastically reduce work load involved with manually entering data into a construction management system, additional development work could facilitate easier and more systematic entry of data directly relevant to work zone safety and mobility performance measurement. For instance, field identification of work locations for each shift, any road or lane closure information (locations, number of lanes closed, start and end times) could be very easily recorded on a mobile device and stored in the database.

Electronic database of agency maintenance work – Many agencies do certain types of work with its own forces out of its area offices or maintenance yards. These activities generally are tracked by type of work task completed and location in some type of daily work diary to assist in assigning staff time to various accounts, but these data are not generally coded into any type of database that is tied to roadway locations. However, a few agencies are beginning to recognize the value of tracking these maintenance efforts, and have developed maintenance management systems that in many ways mimic those of the traditional construction management databases.

6.1.3 Key Considerations and Trade-Offs of Work Zone Efficiency and Productivity Data Sources

Table 6-1 provide a summary of some of the key considerations and trade-offs associated with the various construction productivity and efficiency data sources. Although mobile applications for field entry of project activities do currently exist, collection of MOT data of interest for work zone safety and mobility performance measurement can be recorded in these applications will depend on whether the underlying database being populated (i.e., the construction management database) has field structures and elements that allow the data to be input from the mobile device.

Table 6-1. Considerations and Trade-Offs of Construction Productivity and Efficiency Data Sources

Data Source	Key Considerations and Trade-offs
Construction management system databases	Focus of most systems is still mainly on contract-related data (quantities, task completion levels) Many of the MOT data elements of interest are entered via narratives into the system, with minimal consistency in entries across projects
Lane closure request and approval databases	May include closures across all agencies and contractors in a region Will normally be limited to high-volume roadways only Depending on administrative processes established, the database may contain a large number of “phantom” closures that need to be removed prior to analyses
Daily project diaries	MOT data entered (if any) often varies significantly from project to project
Mobile applications for field entry of project activities	Requires field personnel to carry and use mobile devices in the field (costs and durability of the devices may become an issue) An application of this type may not yet exist
Maintenance management system databases for agency staff	Requires detailed recordkeeping of activities by all maintenance crews and crew members

6.2 Identifying and Computing Specific Work Zone Efficiency and Productivity Measures

Table 6-2 presents four types of construction productivity and efficiency-related performance measures that could be useful for work zone safety and mobility performance measurement. Level of activity, expressed as a percentage of possible days that could be worked, was cited as a high priority measures by the expert panel that reviewed and rated the measures. A measure of compliance with agency-established MOT criteria (i.e., the percent of lane closure hours occurring outside of accepted work windows) was also cited as a high-priority measure. Various types of traditional construction productivity measures that could be stratified based on roadway type, type of MOT used, construction methods used, etc. was considered a moderately-high priority. The panel also rated one specific type of construction method, the percentage of activities involving a temporary lane closure, as a moderate priority measure, due to its direct relevance to operating conditions and safety of the traveling public. Finally, a measure of average time between work efforts on a given roadway segment was not specifically rated by the panel, but was included in the table as a way to encourage the long term tracking of such work efforts by agencies and contractors in the future.

Table 6-2. Examples of Specific Agency or Contractor Efficiency and Productivity Performance Measures

Measure	Computations Required	Value or Importance Ranking	Potential Audience(s)
Percent of allowable or total days worked	Determine the actual number of days worked and divide by the total number of to date (either the allowable work days or calendar days)	High	Work zone design practitioners Work zone operations practitioners
Percent of lane closure hours occurring outside established “work windows”	Determine total amount of lane closure hours occurring outside of accepted time work windows, divide by the total number of lane closure hours that have been worked (this should be a very low percentage)	High	Work zone design practitioners Work zone operations practitioners
Typical work productivity measures stratified by type of project MOT, construction acceleration technique employed, etc.	Average productivity measures of interest across multiple projects having the same MOT in place, using the same type of construction acceleration technique, etc.	Moderately High	Work zone design practitioners Work zone operations practitioners
Average hours worked during work activities involving temporary lane closures, possibly stratified by time of day, weekday versus weekend	Determine total hours of work activities that involve temporary lane closures, divide by the total hours of work activity overall or for specific time periods of interest	Moderate	Work zone design practitioners Work zone operations practitioners
Average time between work zone activity, possibly by type of work being accomplished, construction methods used, etc.	The frequency of work efforts (construction, maintenance, or utility) over time on a roadway segment, divided by the total time that such activities were tracked	Not rated	Work zone design practitioners

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