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Advanced Quality Systems: Guidelines for Establishing and Maintaining Construction Quality Databases

CHAPTER 3. STATE PRACTICES

To expand the knowledge base on the contents and formats of construction quality databases beyond that gained from reviewing published literature, a survey was developed and distributed to several SHAs that were willing to participate. The main goal of the survey was to assimilate information nationwide with regard to collection, storage, and management of various construction quality-related items. The results of the survey helped identify best practices with respect to SHA collection and use of project-generated data to help make construction QA decisions. The findings formed the basis for guidance to be provided to all SHAs to develop the various components of an “ideal” or a model construction quality database.

3.1 SUMMARY OF SURVEY RESULTS

3.1.1 Survey Design and Agency Selection

As mentioned previously, the survey developed in this study was expanded from a 2004 FHWA survey administered to four SHAs; those being Arizona, Kansas, Louisiana, and Pennsylvania. The expanded survey included queries grouped into the following major categories:

• General database related queries.
• QA program management queries.
• QA data collection queries.
• QA process queries.
• Queries regarding database integration.
• Specifications and standards related queries.
• Data analysis queries.

The project team disseminated the survey electronically to key personnel at selected agencies known to have a construction quality database system in place and willing to participate in the survey. These States included Georgia, Minnesota, Washington, New Jersey, Florida, Texas, Oregon, and Maryland.

The personnel whose input was sought during the survey process were those responsible for monitoring construction quality and the collection and use of construction quality data within a given agency. These included State materials and construction engineers, as well as pavement management, design, and research engineers. Also included were agency staffers who are involved in developing, maintaining, or using various other agency databases.

A summary of the agency responses to both the 2004 FHWA survey and the expanded survey performed in this study is presented in the sections below.

3.1.2 General Database-Related Queries and Summary of Agency Responses

Under this category, aspects regarding each agency’s database systems were queried, including the number of databases in which construction quality information is stored, data types stored in each database, objectives/purpose of the databases, ownership, data entry duties, data access rights, database platform, database security, extent of project coverage reflected in the database (e.g., all construction projects, warranty projects, design build projects), year in which the database was initiated, linkage with other databases, adequacy of database in meeting agency needs, and other aspects.

The following were the highlights of the agency responses under this category:

• Among the agencies surveyed, the oldest construction quality database appears to be in Louisiana, initiated in 1978 by S.C. Shah. Arizona, Washington, Pennsylvania, and Maryland had databases dating back to the late 1980s or early 1990s. Kansas, Georgia, Minnesota, Florida, and Texas had implemented their systems in the mid- to late 1990s or later.
• Prior to the development of modern construction quality database systems, cumbersome mainframe-based database applications, legacy systems, or paper reports were used to store data. In some instances, there was no central repository to store information.
• Seven of the nine respondents have multiple databases to track construction quality data. Separate databases exist for laboratory testing data, QA data, IA data, etc. Washington and New Jersey reported having a single database.
• A majority of the agencies surveyed have developed their own database systems for construction quality data storage. The SiteManager module of the AASHTOWare Trns*port suite of construction management software and the Laboratory Information Management System (LIMS) databases are used by two of the nine responding agencies.
• Six of the seven respondents noted that their database systems are stand-alone. A major drawback perceived by the several survey respondents was the lack of linkage between the construction quality and performance databases.
• As far as types of data stored, project material classification records, daily construction records, test data, and supplier material classification tests are stored in the databases. Pavement performance information is not stored by any of the agencies surveyed, and instead stored in an independent PMS. However, there seems to be no automated method to link performance with construction quality information, although one agency indicated that performance data can be linked with quality data with considerable effort. The main difficulty in establishing a connection between these construction quality and performance databases is due to the different referencing schemes by these databases.
• The main uses of the database were to allow (1) document tracking through the life cycle of the project, and (2) store acceptance and assurance testing results for asphalt concrete (AC), PCC, and soils. Some agencies report use of the data to perform analyses for management and engineering purposes. However, a majority of the agencies would like a broader use of the data (e.g., to perform materials and performance correlations, improve acceptance procedures, update specifications). For example, Arizona is implementing the "ADOT Information Data Warehouse" to utilize their construction QA database, Field Office Automation System (FAST), for ad-hoc reporting.
• SHA field offices responsible for QA are responsible for entering acceptance testing data into the database in a majority of the agencies surveyed. In some cases, this is the project residency personnel or project engineer. In one agency, all data entry is done by Central Office personnel. Contractor access to the database to enter QC data is not very common; however, one agency responded that this is possible in their system for design-build projects. SHA materials lab personnel enter the materials testing and mix design data.
• Mostly construction or materials offices within the agencies surveyed own complete rights to the quality databases.
• In nearly all agencies surveyed, access to the database is controlled by hierarchically set login passwords. Access varies by the roles and responsibilities of each individual or division within the agency. Basically, all personnel who need to access a database can access it, including technicians, supervisors, engineers, and contractors. In many agencies, access is restricted to agency personnel only (i.e., contractors or other outside personnel do not have access).
• Nine of 10 survey respondents noted that either most or all conventional construction projects undertaken are represented in their respective construction quality database. Only Minnesota reported that the database is used strictly for design-build projects only.
• Three of the six respondents stated that some segment of the database (test data) is updated on a real-time basis. The others update as needed or at periodic intervals.
• Six of seven respondents stated that while their individual databases may be addressing current needs, improvements are needed to provide (1) a more efficient and comprehensive system (2) a system that is more user-friendly (3) a system that can be linked to other databases, and (4) a system that allows more efficient analysis and reporting.

3.1.3 QA Program Management Queries and Summary of Agency Responses

Under this category, the roles and responsibilities of the various individuals involved in the agency’s QA program were queried. Offices and personnel involved with QA data oversight, upload, and storage within each agency were determined, and the nature and administration of IA programs was synthesized. Finally, written procedures, manuals, and documents related to the QA program and its management were collected.

The following were the highlights of the agency responses under this category:

• In most agencies, the responsibility for management and oversight of the QA program lies with either the construction (project field offices) or the materials divisions (laboratories), which are also the owners of their respective segments of the QA databases.
• In agencies that have implemented agency-wide, client-server based QA database systems, the central office has electronic access to the data entered by field offices. This appears to be the case in eight of the nine agencies that responded to the survey question. One agency that did not appear to have such a feature implemented at the time of the survey, reported communicating project information to the central office via hardcopy reports (flat files).
• IA programs are handled by the SHA. All responding agencies indicated that no external agencies or consultants are involved in this process. Most agencies surveyed also do not use contractor QC results for acceptance decisions; agencies perform their own acceptance testing or supplement QC results with independent verifications. The procedures sometimes vary for asphalt versus concrete pavement construction projects.
• QA specifications are most frequently used for testing HMA materials. However, the acceptance of concrete, unbound materials, and earthwork materials varies. For these, some use method specifications or run a verification program.

3.1.4 QA Data Collection Queries and Summary of Agency Responses

The parties responsible for collection of data for the applicable testing, and the respective tools used to collect the data were queried in this category. The types of test data contained in the database (e.g., contractor QC, agency validation, IA) and how they are aggregated and referenced in the database were also determined. In addition, it was also ascertained if other pertinent materials- and construction-related project information (e.g., mix design, inspector notes) and other relevant data (e.g., plant, equipment, contractor, weather, stationing or mileposts) could be stored in the databases.

The following were the highlights of the agency responses under this category:

• Most often, data from the plant, field, or testing laboratories are collected using standard forms or datasheets. Data entry is either electronic or manual. Electronically collected data are directly uploaded from the field offices to the central QA database. Manually completed forms and spreadsheets are sent into data entry stations at the field offices or central labs via faxes, emails, or hardcopies to be entered into the electronic databases.
• All agencies surveyed have a clear set of instructions to ensure uniformity in the data collection practices. Some database applications provide online help to guide the users.
• Four of the eight responding agencies stated that hand-held devices are used to collect a portion of the QA data. For example, Arizona’s FAST system supports pen-based data entry, where field technicians/inspectors can create test header cards and input test data for later download to the database. Georgia’s Weekly Concrete Report has been automated to several hand-held devices. The reports are then downloaded to an Excel^® spreadsheet or a Microsoft Access^® database. Two agencies that use AASHTO’s SiteManager software also use a hand-held electronic data entry tool.
• The QA databases of a majority of the agencies responding (seven of nine) allow test results from an IA unit outside the agency or a unit within the agency with no ties to construction to input data into the database.
• Examples of QA data stored in the database for asphalt materials include mix design, binder information, air voids, and densities. Strength and thickness are very commonly stored for concrete materials. Pavement smoothness after construction is also stored for both asphalt and concrete pavements. Other data items that are recorded in the database systems of most agencies (7 of 10) are contractor, plant, weather, distance from plant, hours of paving, type of curing (for PCC pavements), beginning and ending mileposts, course/lift, station, distance from center line, and opening to traffic. These data may not be readily queried, but can be found in log books, inspector notes, etc.
• All agencies surveyed sort and store the QA data by (1) project (2) lot, and (3) date/day of construction. Georgia stated that the data are also arranged by milepost or reference marker. Only two of the nine agencies surveyed stated that the data are also organized by time of construction, sampling, and testing.
• All agencies surveyed indicated that they record individual test results. When replicate testing is performed (e.g., compressive strength cylinder breaks), most agencies record information from each test. When tests are repeated (e.g., referee tests), these data are maintained in the database by most agencies surveyed using appropriate remarks.
• In a majority of the agencies surveyed, the test procedure used is identified along with the party responsible for sampling and testing (e.g., contractor, agency).
• On the question of whether their QA database systems accept contractor QC test results as well as agency’s verification test results, 50 percent responded in the affirmative and the remainder in the negative. However, Washington indicated that they are in the process of implementing a new system that will allow outside input into the database.
• A majority of the responding agencies (six of eight) reported that control strip information is not typically recorded with the QA data. However, it appears that the database systems generally support uploading such data into the system. Kansas reports that some test strip information is stored at the District level. Texas reports recording test strip information for asphalt paving (which basically is the first day’s production).

3.1.5 QA Process Queries and Summary of Agency Responses

The focus in this part of the survey was to gather information on the processes used by the agency to control quality on a construction project (statistical control charts, run charts, etc.) and procedures used in acceptance testing (percent within limits [PWL], percent defective [PD], etc.).

The following were the highlights of the agency responses under this category:

• Agencies stated that the type of QC exercised is a function of the material type. For asphalt materials, four of the seven responding agencies stated that statistical control charts are used for QC.
• Control charts are not included in the SiteManager software used by some agencies. One agency stated that contractor option is used to exercise QC.
• Five of the eight responding agencies state that PWL specs are used for acceptance testing. Other acceptance testing approaches, such as absolute average deviation (AAD) and lot averages, are used by other responding agencies. Averages of test results are used for acceptance of asphalt and concrete pavement surfaces based on smoothness criteria.
• End-product HMA criteria used for PWL specifications include asphalt content, effective air voids, compaction/density, and smoothness. For PCC, compressive strength and thickness are commonly used.
• In Minnesota, where the QA database system is solely populated with design-build projects at this time, the incentive/disincentive payments for concrete paving are based on:
  • Aggregate Quality—statistical acceptance based on averages and variances for entire production (based on agency results).
  • Concrete Mix Quality—based on average daily results of water/cementitious materials ratio by a lot basis (minimum of 3 tests in a lot). Moistures and Microwave Oven testing are performed by the agency.
  • Combined Aggregate Gradation Quality—based on the 8-18 chart to test for well-graded aggregates. Average results on certain set of sieves using the percent retained by a lot basis (minimum of three tests in a lot). Payment based on contractor results as verified by the agency testing.
• In Arizona, aggregate properties (sand equivalency, fractured coarse particles, uncompacted voids, gradation) and material spread are used as additional measures to monitor quality of the HMA end product and percent cracked slabs for PCC end product.

3.1.6 Database Integration Queries and Summary of Agency Responses

Under this category, the project team asked about any existing integration of the construction quality database with other databases (design, construction plans, maintenance, pavement management, etc.).

The following were the highlights of the agency responses under this category:

• Overall, it was found that most agencies do not have an easy facility to link QA information with other agency databases such as design, construction plans, traffic, maintenance, condition surveys, and accident history information. All these databases exist separately and are owned by different units within the SHA. However, some agencies have indicated that this information can be linked if requested.
• About half the responding agencies indicate that project cost information is linked to construction QA data on a project-by-project basis.

3.1.7 Specifications and Standards Related Queries and Summary of Agency Responses

Queried under this category were the types of specifications used within an agency (conventional QA, PRS, warranties, etc.), checks and balances in the construction process triggered by QA database, data used for setting performance standards on warranty projects, and pay factor calculation methodologies and basis. Of particular interest was the type of information that is stored and its uses, particularly in relation to the development of QA specifications and the subsequent evaluations of how the specifications are working.

The following were the highlights of the agency responses under this category:

• A majority of the responding agencies (five of seven) stated that they use conventional QA specifications (QC by contractor and acceptance by agency) for their projects.
• PRS are not used at this point by any of the agencies surveyed. However, Texas and Georgia have specifications for wheel tracking tests to evaluate asphalt mixture susceptibility to permanent deformation or rutting. Also, Texas noted that most of the agency’s specifications are evolving into PRS.
• Three of the five responding agencies stated that specification non-conformance is highlighted by their current QA system. In this event, construction can be suspended at the discretion of the engineer and based on warnings issued to the contractor or the frequency of problem recurrence. It is not clear if this possibility is put into practice based on the survey.
• It was found that specifications or special provisions governing construction are not always part of the QA database.
• In a majority of the cases, agency test results are used to validate contractor-performed testing.
• Of the agencies that validate contractor test results, only Kansas makes the validation test statistics (e.g., F-test and t-tests) available as part of the QA database.
• Referee testing is an option available in most specifications.
• Calculated and/or applied pay adjustments are available in most agency databases on a lot-by-lot basis. Pay factors are calculated if actual specifications govern. Otherwise, they are applied.
• Some of the agencies surveyed state that specification tolerances and pay factors are derived based on historical data.
• Warranty-type projects are not common in many of the agencies surveyed. Only Minnesota, Florida, and Washington indicated that they have done some warranty type projects. All design-build projects in Minnesota and Washington are built to warranty specifications. The types of warranties range from materials and workmanship (more common) to more comprehensive performance warranties. Both new and rehabilitated asphalt and concrete pavements have been subject to warranty specifications.
• On a majority of the projects, warranties last from 2 to 5 years. Florida has some projects that are under 10-year warranties.
• Most agencies that use warranties use pavement structural and functional distresses during the warranty period as the choice performance measure. Historical data appear to have been used to set performance goals on these projects.
• QA data from warranty projects are part of the QA databases of agencies that use this type of contracting.

3.1.8 Data Analysis Queries and Summary of Agency Responses

Covered under this category of queries were the types of data analysis supported by the databases and the amenability of the database to perform a variety of engineering analyses and provide valuable feedback to agency on issues such as quality improvements, design, specification revision, pavement management, and research. The focus was on the States’ collection and analysis of test results and of other descriptive materials and construction information for both asphalt and concrete paving projects.

The following were the highlights of the agency responses under this category:

• Target audience for data analysis appears to be SHA personnel at construction, materials, and pavement management offices as well as FHWA staff in some cases. These include project resident engineers, upper management, project personnel, materials staff, and specification committee members.
• Uses of the data include (1) settling testing disputes on projects, (2) evaluating work done by contractors in various districts of the agency, (3) monitoring trends with time and different pavement materials, and to (4) monitoring performance. However, agencies did report that data analysis was cumbersome and that more analysis can be performed if the data interfacing was more user-friendly.
• Most agencies state that representative project or lot statistical parameters can be determined for QA (e.g., mean and variability, PWL). However, data analysis is time-intensive at this point due to inability to generate ad hoc reports.
  • Project or lot statistical parameters are used mostly to pay the contractor. However, these statistics are also used in some of the agencies to monitor and refine QA programs and for research purposes.
  • The parameters are also used in developing new specifications or validating and revising existing specifications in three of the seven responding agencies, sometimes in one agency, and not used at all in the remainder of the agencies.
• A majority of the responding agencies state that their QA data can be analyzed on a project-by-project basis to determine whether quality is improving or to check design assumptions. However, such analyses are not commonly performed because of their difficulty, and because there is a lack of easy integration with other databases (e.g., PMS).
• A majority of the surveyed agencies suggested that the data cannot be used to develop performance prediction models due to the inappropriate linkage with other databases. Only two of the eight agencies surveyed suggest that this is being currently done.
• A majority of the responding agencies suggest that the data in the QA database systems can be analyzed to assess contractor performance (e.g., comparing contractor QC data with verification data). This appears to be of interest to agencies and they routinely perform this analysis on individual projects despite significant problems with data integration.
• Other types of analyses that are routinely performed include computing overall incentive/disincentive on a project-by-project basis, overall maximum pay adjustment, etc. Arizona reports that their yet-to-be-released Information Data Warehouse system has ad hoc reporting capabilities. This allows data to be custom-queried and extracted quickly so the user can now perform analyses of materials characteristics that, in the past, were very difficult to perform. This will likely pave the way for more in-depth engineering analysis of QA data to improve existing specifications, practices, and quality of pavement structures.
• It also appears that a lack of dedicated positions within an agency to perform data analysis limits the amount of analysis that can be done.
• None of the agencies surveyed appears to have performed a cost-benefit analysis of maintaining a high-quality QA database system. As a result, the potential benefits of such systems may not be fully realized.

3.2 DETAILED INVESTIGATIONS (BY STATE)

3.2.1 Introduction

In addition to electronic solicitation of information, detailed telephone and on-site interviews were conducted with staff from a few selected agencies. These reviews focused on gathering additional details regarding the database architectures, data types in the databases, data collection procedures, acceptance procedures, data analyses models, and desired features and expected changes in databases. The goal of this exercise was to use the information gathered to establish best practices for each of these aspects of the prototype QA database system that will emerge from this research.

In shortlisting candidate agencies to conduct in-depth interviews, the project team attempted to capture the depth and breadth of nationwide practices with regard to storing and using construction quality data. Based on this criterion, the project team selected Arizona, Georgia, Washington, and Texas to conduct further in-depth reviews of various aspects of their construction quality database systems. A detailed telephone interview was conducted with Arizona personnel, and on-site interviews were conducted with staff from the remainder of the agencies. The information obtained from these interviews is summarized in this section.

3.2.2 In-depth Review of ADOT Construction Quality Database Systems

Philosophy of Quality in Highway Construction at ADOT

ADOT uses a two-pronged approach to ensure highway construction quality. Their materials QA program, established in accordance with Title 23, Part 637, Code of Federal Regulations, (FHWA, 1995), is intended to ensure that all materials incorporated into ADOT projects satisfy specification requirements. The program embodies a traditional approach to QA, with the contractor responsible for QC testing, and the Department responsible for acceptance and IA testing. An incentive/disincentive program is employed to reward/penalize contractors based on key HMA and PCC materials and construction properties.

ADOT’s construction workmanship program utilizes a comprehensive inspection checklist to monitor conformity of construction products and processes to standard specifications and drawings. The quantified checklists utilize the method of attributes (i.e., pass/fail, yes/no) to allow quick and inexpensive checks on thousands of individual requirements not covered by material tests. Incentives are used on design-build projects, with incentive payments based on the number of reworks.

The Department’s materials QA program is administered by the QA Section of the Materials Group, while the construction workmanship program is managed by the Construction Operations Section of the Construction Group.

Database Architecture

Two databases are used in storing and accessing data for the materials QA program: the Central Materials Testing Program (CMTP) and the FAST. The CMTP is used to enter, calculate, track, and report on the various samples and testing methods used in the central office lab (Wiechman, 2005). The major testing areas included in the program are soils and aggregate, AC mix design, and asphalt binder material testing. The FAST system handles remaining acceptance data obtained in labs other than the central office lab. Types of data captured in FAST are sampling and testing information for soils and aggregate, AC, and PCC.

The construction workmanship program utilizes a Web-based, SQL database system to store and access checklist data that cover all major specification sections and many standard drawings.

Like the FAST and CMTP systems, the Construction Operations Checklist Application (COCA) also resides on the Department network.

Construction Quality Related Systems

A summary of the three database systems used by ADOT to monitor and report on construction quality is presented below:

• FAST—Implemented in 1993 and since modified on various occasions, FAST can be used by field and lab personnel responsible for sampling and testing soils and aggregate and AC and PCC materials associated with most ADOT projects. The FAST database is a Microsoft SQL Server 2000^® system. It accepts both acceptance and IA data. The data can be categorized by project, material type, lot, and individual test numbers. Both individual test results and averages are accepted by the system, as well as the results of repeated tests. FAST is client-server based, with varying levels of access afforded to individual (i.e., technicians, supervisors, engineers, administrators) and group users (different labs). Data entry for the system is based on hard cards, and the system supports a pen-based data notebook, where field technicians/inspectors can create test header cards and input test data for later download. Data analysis is primarily available on project-by-project basis, with PWL, averaging, and other techniques used in determining acceptance and calculating pay factors. The system has some interactivity capabilities with CMTP and ADOT’s Advantage financial system. However, linkages with other databases, such as the pavement management and traffic databases, are limited due to different referencing systems (i.e., stations versus mileposts).
• CMTP—The CMTP is a relational database which can be used by field and lab personnel for AC mix designs, as well as sampling and testing of soils, aggregates, and asphalt binder. Although not as comprehensive as the FAST system, CMTP has several of the same features as FAST, is reportedly more efficient and easier to use, and has good ad-hoc reporting capabilities. Like the FAST system, CMTP can interact with the Advantage financial system, but is limited in linkages with other databases.
• COCA—First implemented in 1994, a third-generation version of COCA is currently being implemented. The program operates off an SQL platform in a client-server environment, but off-line usage for data entry is an option. Data are entered by construction personnel using portable computers or via downloads from laptops. Standard checklist forms are embedded within the program for data entry, with inspection results capable of being added by project and lot (one checklist typically represents 1 lot). Data are not directly compatible with other agency systems.

Data Input and Analysis

Many different quality characteristics are evaluated in the materials QA program. QC data include sand equivalency, fractured coarse particles, and uncompacted voids for aggregates used in end-product AC mixes; effective voids, gradation, and asphalt content for end-product AC mixes; and edge slump for PCC. Acceptance of AC and PCC materials is based on the following quality characteristics and quality measures:

AC

Asphalt content and gradation: disincentive pay factors based on PWL. Effective voids: incentive/disincentive pay factors based on PWL. Material spread (i.e., thickness): average variance from required thickness, as determined by actual versus theoretical tonnages. Compaction/density: incentive/disincentive pay factors based on PWL. Smoothness: incentive/disincentive pay factors based on IRI and pay factor equation.

PCC

Compressive strength (28-day): incentive/disincentive pay factors based on PWL. Thickness: incentive/disincentive pay factors based on PWL. Smoothness: incentive/disincentive pay factors based on profile index with a 5-mm (0.2-in) blanking band (PI5.0).

It should be noted that input of end-product PCC data into FAST is not currently available.

Beyond analyses for QC, acceptance, and IA functions, the types of analysis performed by ADOT using FAST/CMTP data pertain to evaluating the performance of various materials and techniques. Such evaluations, however, require that data from the PMS and other databases be extracted and properly matched with the construction quality data, which is not an easy task.

In addition to assessing contractor’s/subcontractor’s conformance to specifications (and determining incentive payments on design-build projects), analysis of COCA data can be done to examine Departmental performance, inspection management applications, and specification requirements.

Future Directions

The FAST system is reported as being fairly comprehensive, yet somewhat difficult to use. In particular, the ability to extract data on a global basis and to perform ad-hoc reporting is limited. An effort is currently underway within ADOT to improve the FAST system in these and other areas (e.g., input of end-product PCC data). Some aspects of the CMTP system, such as the interfaces and ad-hoc reporting capabilities, are being considered in the update. Also, ways of linking FAST/CMTP and other databases are being contemplated.

The construction workmanship program is expected to be further expanded and used in the future, quite likely to the point of forcing resident engineers to learn it by a certain time period. The COCA system is currently being upgraded, primarily in the reporting capabilities area.

3.2.3 In-depth Review of GDOT Construction Quality Database Systems

Philosophy of Quality in Highway Construction at GDOT

GDOT places a lot of emphasis on ensuring quality even before the materials are constructed in the field. GDOT has in place a certification management system to ensure that their technicians are qualified and asphalt plants (for example) are rated based on the quality they produce (assessed from QC records). GDOT also pre-qualifies material suppliers and producers and uses accredited laboratories. This QA system could potentially reduce the cost and effort required to ensure quality during construction.

Database Architecture

The Office of Materials and Research (OMR) at GDOT manages and operates several database systems and applications related to materials and construction quality. Each department within OMR has specific functions with regard to QC with little or no overlap in their day-to-day activities. This is partly the reason why their database systems have developed independently and currently do not interact.

The level at which OMR systems are automated across its functional areas is heavily geared toward sample testing and data storage. The least amount of automation is in test results distribution. As such, a large portion of the systems in place focus on the management of samples, testing of samples, and printing of test results. Table 4 shows the distribution of information technology (IT) systems by platform (Access^®, Excel^®, etc.) across the four key business areas.

Table 4. Distribution of systems across functional areas at GDOT OMR.

Functional Area	Access® SQL	Excel®	Computer Application	VAX	Word® or Paper-based	Total
Certification Management	6	1	1	1	2	11
Equipment Management	0	2	0	1	0	3
Investigations	8	7	12	2	5	34
Sample Management	6	11	0	2	12	31
Total	20	21	13	6	19	79

Construction Quality-Related Systems

A summary of the systems currently used to collect and store testing data related to construction quality is presented below:

• Field Data Collection System (FDCS)—Used by test engineers in the field and producer QC technicians to collect various information regarding soil, concrete, asphalt, raw materials, fences, and other OMR-certified materials. It is a collection of data entry forms for different GDOT specifications. The system has two main functions: a field-deployable portion that field engineers use to capture data and test results, and a centralized portion that is used by the OMR staff in Atlanta to aggregate test results across the State into a single location for use in reporting and analysis. Both parts of the application are based on an Access^® 97 platform that has been highly customized with external Visual Basic^® 6 application extensions. FDCS is used by several branches (Concrete Services, IA, Pit and Quarry, Inspection Services, Testing Management). Data are stored in an Access^® database. It can be used to calculate pay factors based on test result data and plant ratings. The program can operate as a stand-alone application or within a server-client environment.
• PhysChem—Stores and maintains laboratory test result data in an Access^® database for 24 materials test types performed by the Physical and Chemical Testing Branch, including reference data for approved sources and material codes.
• Concrete 319—This form is basically a paper report containing results of tests performed on concrete cylinders. The application that yields the data required for these reports is called Concrete Cylinder Test Reports. This application is mainframe-based.
• Pavement Testing—This database is an incomplete application which is currently used exclusively for storing results from roadway tests (smoothness) in order to generate reports required by the FHWA. This application was built using Access^® and was anticipated to address more test areas than it is currently being used for. Once the application is completed, it is anticipated to include all the functionality currently offered by the old VAX systems and spreadsheets. The Access^® application uses a SQL Server database.

Future Directions

GDOT has embarked on the path of developing a customizable software product, Materials Information Management System (MIMS), to improve the efficiency, accuracy, and integration of laboratory and field test samples tracking and reporting. Figure 5 presents line diagrams detailing how the various database systems within the GDOT will interact with MIMS. The software and associated databases will be centrally located and accessible by users throughout the State; access will be through an internet/intranet environment to provide a larger base of accessibility in remote locations. The improvements to current systems involve automating various OMR processes via interactions with shared databases and selected testing equipment. MIMS data will be used to support QA activities that include statistical analysis of material test results. MIMS will have the ability to securely upload or import QC test data from external sources (e.g., vendors, contractors, consultants).

Figure 5. Conceptualsketch of GDOT’s planned integrated database systems (courtesy GDOT).

A key success factor is the ability to track the progression of samples from collection, receipt, and testing through the reporting of test results to GDOT personnel. Test data may be collected in the laboratory or at the construction or plant sites with portable devices (e.g., laptop or Personal Digital Assistant [PDA]) and then transferred to the central database. Construction project-based information will be used by the Materials Audit process for issuance of the Materials Certificate. The ability to interact with the AASHTOWare Trans *port’s Contracts Administration Module (CAS), of which GDOT is a licensee, is desired.

Overall, it appears that GDOT has in place a number of database and software systems created independently to serve specific functions for the different department groupings within the OMR. The primary shortcoming of the current system is that these databases are not integrated, although efforts to address this are underway with the development of the MIMS system. The MIMS system is structured to address construction quality—emphasis is placed on ensuring quality through certification of technicians and material producers.

Construction QA is addressed within MIMS. This information is used not only to flag non-conformance but also to calculate pay factors and quality ratings for material producers (e.g., asphalt plants). A concern expressed by GDOT is that currently no link is in place to relate material information collected as part of the QA process with performance information (e.g., rutting, cracking, roughness, friction). There is a great of deal of interest in doing such linking. It is also not clear if this will be addressed by MIMS.

3.2.4 In-depth Review of TxDOT Construction Quality Database Systems

Philosophy of Quality in Highway Construction at TxDOT

Traditionally, TxDOT’s construction quality-related materials testing programs included direct sampling and testing of the work performed by the contractor on-site at the project or at a supplier’s plant for control of the construction job. The emphasis is now changing to sampling and testing done by the supplier or contractor, and sampling and testing by TxDOT for verification purposes. TxDOT is moving its efforts to monitoring techniques and programs where particular material suppliers go through a certification process that is periodically updated, independent of a particular construction project.

Construction Quality-Related Systems

TxDOT uses multiple databases to store and access information with regard to construction quality. Descriptions of the various databases are provided below:

• AASHTOWare Trns *prt SiteManager—This client/server application is the main database for all construction quality-related data used by TxDOT. SiteManager was implemented as a pilot project in 1999 in two districts. Based on the success of that test, the program became fully operational in 2003. Information and data from all construction projects go into SiteManager, including testing data, daily reports, payment quantities, change orders, bid items, mix design records, and construction diaries. All project information that is input into SiteManager has a Control Section Job (CSJ) number. Without the CSJ number, information cannot be tracked or extracted from the database. Access to the database is set up at 20 different levels within TxDOT. Each level can access certain portions of the database that affect their operations. Data are entered into SiteManager by field construction personnel. The Construction Division owns this database, and the Information Systems Division maintains it.
• Calibration Manager—This database is used to track the calibration of all test equipment in terms of certification for the AASHTO Material Reference Laboratory (AMRL), the Cement and Concrete Reference Laboratory (CCRL), etc. This database is not linked to SiteManager. This database is used by all districts.
• Proficiency Database—This database is used to track the certification for all personnel. It is tied to SiteManager in terms of personnel that are authorized to complete tests for construction projects.
• LIMS—This database is used by the materials group. All materials test data goes into this database. It is a stand-alone database and not linked to SiteManager.
• Letting Database—This database is for general information and data on construction projects. The letting database was used on a research project, which is still on-going, to track and evaluate Superpave mixtures.

Data Input and Analysis

The SiteManager database contains detailed information and data on each construction project. It includes QC, acceptance, and IA data. Data are aggregated by project (CSJ) number, lot number, and by day. Individual test data, including replicate and referee testing data, are entered into the database. HMA materials require control charts; however, these are not entered into the database. Data are collected using paper forms or hand-held portable pen-based devices. Laboratory materials data are collected on spreadsheets for the LIMS database.

The data are used to calculate means, variances, pay factors, etc., on a lot or project basis. The data can also be used for forensic studies. However, the data analysis beyond contractor payment-related calculations is limited at the present time because of the labor-intensive nature of data extraction and linkage with other performance and materials databases.

Future Directions

Overall, it appears that SiteManager is meeting the needs of the TxDOT in terms of what it was originally developed to do (i.e., serve as a contract management tool). Some of the perceived shortcomings of SiteManager are (1) it is not user-friendly, (2) it takes a lot of time and resources (e.g., high-speed Internet access) to enter and use the database, and (3) it is not linked to other agency databases, such as the PMS and materials databases. This limits the usefulness of the data included in SiteManager. There are plans to consider linking all of these databases; however, it may take several years before this goal is realized.

3.2.5 In-depth Review of FDOT Construction Quality Database Systems

Philosophy of Quality in Highway Construction at FDOT

FDOT’s State Materials and Construction offices are involved with ensuring that the materials used in transportation construction projects meet the required specifications and are built in accordance with departmental standards. Specifically, the Quality Systems section is responsible for providing the methods and measures for QA in testing, inspection, and evaluation provided by the State Materials Office (SMO). This section also provides support for the Office of Construction, other units of the SMO, and District Materials Offices in assuring the quality of materials incorporated into the department’s projects.

FDOT has an active IA program, departmental and private sector laboratory qualification program to certify testing laboratories, a materials acceptance program to certify material sources and products, and a producer certification program. Extensive checklists exist for QC of various construction materials and guide list for the construction of various work items. In other words, a lot of emphasis is placed in pre-construction quality and to ensure uniform and standard practices during construction across the department. FDOT makes extensive use of design-build contracting on construction projects and warranty specifications. A total of 184 HMA projects and 7 PCC projects have been constructed to date under warranties that extend from 3 to 10 years.

Construction Quality Related Systems

The database systems used by FDOT to store and access information with regard to construction quality are:

• AASHTOWare Trans*port SiteManager—This database was implemented in 1996 and covers contract administration processes after the contracts are awarded. It is implemented on an Oracle^® platform and currently has 1,100 to 1,300 users statewide. Access is password protected and applications to access are available through a Metaframe server which can be reached by local area network (LAN) or virtual private network (VPN).
• Electronic Document Management System (EDMS)—EDMS is a two-part system—construction document management system (CDMS) and Materials Document Management System (MDMS). MDMS is currently under development. EDMS, along with SiteManager, is managed by the State Construction Office.
• LIMS—This database is used by the State Materials Office. It covers all materials processes, including testing, laboratory qualifications, producer qualifications, qualified products, technician qualifications as used in sampling and testing, final project material certification, and the IA program. LIMS gets information from Trns*port and will also interact with MDMS when it is fully implemented. Access to LIMS is password protected and it too has between 1,100 and 1,300 users statewide.

The purpose of the construction quality databases is to track performance, project acceptance, specification update, pay item update, and to provide efficient data collection (automation), and effective information generation (reporting).

Data Input and Analysis

The quality databases include a data side and a document side. On the data side, various forms of data collection are used (e.g., spreadsheets, paper forms, emails, faxes). Construction inspectors and technicians use hand-held portable devices in conjunction with SiteManager for automated data entry for testing. The LIMS database has been customized by FDOT and allows independent QA test results, contractor QC results, agency’s validation test results, and project acceptance test results. Data are grouped by project number, contract number, road number, and pay item number.

Examples of types of data stored for the various materials includes:

• HMA—Air voids, binder content, gradation information at the plant. Density and smoothness on the roadway. Pay factor information for all quality characteristics as well as composite pay factor by lot (smoothness does not have a pay factor). Acceptance of asphalt materials is based on PWL specifications.
• PCC—Compressive strength, core thickness, permeability/durability, cement content and composition, and temperature at the time of placement. Acceptance of PCC materials on the roadway is based on pass/fail criteria.
• Unbound materials—Density, Limerock Bearing Ratio (LBR), and thickness.

The types of analysis performed by FDOT using the data pertain to evaluating contractor performance on projects, performance of various programs and processes, performance of labs, performance trends of various materials, etc.

Future Directions

FDOT staff cited many difficulties in performing data analysis. As one staff member summed up the situation, the database is “data rich and information poor.” For example, it is very difficult to connect a low pay factor section in the database with a field lot because HMA mix is measured at plant and may be put down in different places during construction. The lack of dedicated staff to perform data analysis was cited as another factor that leads to lack of analysis.  However, FDOT has a great interest to test the right thing in the right way and in the right quantity. Department staff expressed a great deal of interest in improving performance from a materials point of view and recognized that the current systems do not often lend themselves to “closing the loop” on showing improved performance when changes are made to specifications, pay factors, testing, etc. FDOT has dedicated staff to generate reports and work with database issues. In the event performance analysis is to be performed, pavement management staff will have to coordinate with the staff familiar with the database.

Some of the issues that prevent effective data analysis are centered on the lack of a common referencing scheme. FDOT is actively working on this issue. A few options that are being looked into are developing a GIS for data storage and retrieval and the adoption of Extensible Markup Language (XML) schema for transportation applications in a framework to be called TransXML. Both these activities are in development at this time.

3.2.6 In-depth Review of WSDOT Construction Quality Database Systems

Philosophy of Quality in Highway Construction at WSDOT

WSDOT’s State Materials Office is responsible for the management and oversight of the QA program within the State. This office has maintained a very efficient system. The State subscribes to the philosophy that “QC always costs less than removing and replacing,” and ensures that its specifications are met and quality materials used and quality construction is achieved in all department projects. The district offices and project residency are actively involved in the QA program. The Regional Project Engineer is responsible for the collection of data and data storage, and each region is responsible for making data available to the central office through the database maintained by WSDOT. WSDOT conducts all acceptance testing and does not use contractor results in QA.

WSDOT has used a combination of volumetric (gradation, VFA, VMA, etc) and non-volumetric properties (density, binder content) to characterize HMA material and construction quality. The State believes that collectively these two sets of properties measure HMA material and construction quality reasonably well.

WSDOT has just begun using design-build contracting on construction projects and requires warranty specifications on all design-build projects. WSDOT has used warranty specifications on new HMA, HMA overlay, and PCC rehabilitation projects. A 5-year term is used on warranty jobs at this time. For both flexible and rigid pavements, performance is monitored on the basis of ride quality, pavement friction, pavement surface condition, structural capacity, and material quality. Performance is monitored at several times during the warranty life, as deemed necessary by WSDOT. If pavement distress exceeds permissible levels, the design-builder is notified anytime until 60 days prior to the expiration of warranty.

Construction Quality-Related Systems

Washington is one of two States surveyed that maintains a single database to store all project-related information. At the time of the survey, WSDOT was in the process of transitioning from an old database to a new program. The existing system (referred to as the “old database” in this write-up), Quality Assurance Specifications, has been in use since the late 1980s and has undergone two significant upgrades over the past two decades. The program has been used primarily to store HMA and aggregate data and to compute pay factors for the contractors. WSDOT has been involved in relatively fewer PCC projects, so concrete test data are not included in this database; the agency maintains a separate database for storing concrete materials data.

Test data in Quality Assurance Specifications are stored by lots and sublots. The database also stores contract information and mix design information, but does not necessarily provide the framework for storing all test data collected during the construction and acceptance process. The contractor does not have access to this database. The database was developed using a PowerBuilder platform.

The new WSDOT, developed in-house, offers the agency and contractor additional features. This is a Web-based tool and is referred to as Statistical Analysis of Materials (SAM), triggered by the need to monitor design-build projects. The goal was to consolidate data into one large QA construction system that can be used both within and outside the department. Training and reference aids have also been developed to assist the agency in implementation of the system. The conceptual diagram showing a layout of this system is shown in figure 6. The database will hold materials design and test data for HMA, PCC, and unbound materials, as well as maintenance data.

Figure 6. Context diagram for Statistical Analysis of Materials (courtesy WSDOT).

SAM offers advanced security features, and the administrator can customize the system to allow different levels of viewing and data input privileges for various users. It also offers additional analysis features, such as F- and t-test analysis, statistical acceptance, and control charts.

Data Analysis

WSDOT analyses primarily are limited to the calculation of pay factors and standard statistics on test data. These are performed on an as-needed basis external to their existing database system by the agency or the individual conducting the analysis. For example, during the conduct of a recent forensic evaluation of a pavement that experienced early failures (unpublished report), it was recognized that the State had to rely on test data from cores rather than utilize data from obtained during construction. The study, while making recommendations to improve the specifications for aggregate, binder, mix design, and mix placement procedures, also emphasizes the need for an Electronic Project Engineering Office (EPEO) system.

The EPEO system will offer better data collection and analysis capabilities and enable the linking of material properties with pavement performance. The EPEO will also allow agency staff up the chain of command to immediately take note of poor construction and to stop project engineers from modifying pay factors. In addition, the EPEO will make data immediately available to the contractors for their use.

WSDOT also recognizes the benefits of extracting QA data by lots and linking it to performance data from the PMS. At this point, the agency performs this on a case-by-case basis. Such analyses currently require a time-consuming but essential data extraction from the QA database system and linking of that data to the performance data set. The implementation of the SAM database system will address some of these issues. The practicality and effectiveness of correlating test data with performance is yet to be verified. There exists an opinion within the agency at this time that meaningful correlations can only be derived in pavements that have very poor performance, because most pavements built with the State specifications are held to a fairly high construction quality standard. Unless test and material data can be identified for localized areas, the correlation to performance might not be meaningful. These thoughts are to be verified in a future independent study.

Future Directions

WSDOT’s long-term goal is to have contractor QC on all materials for roadway construction. WSDOT will however continue to maintain all acceptance testing. Contractors are now encouraged to develop their own mix designs for HMA, which until recently was the responsibility of the WSDOT.

WSDOT plans to also continue to upgrade the current version of SAM to incorporate advanced features that provide a more user-friendly interface for analysis tools and viewing test results.

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This page last modified on 05/01/07