Guidelines for Optimizing the Risk and Cost of Materials QA Programs (2017) / Chapter Skim
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Research Report P a r t 1
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5 In response to shrinking budgets and dramatic reductions in both the numbers and experience levels of inspectors and engineers, several state Departments of Transportation (DOTs) are seeking ways to improve and optimize their processes to achieve greater efficiencies in resource allocation and project and program delivery.
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6 Guidelines for Optimizing the risk and Cost of Materials Qa programs A DOT's materials QA practices tend to be based on methods that have historically produced satisfactory results. These legacy practices, however, may fail to take advantage of more recent developments in the form of increased understanding of materials behavior, advances in nondestructive testing technology, and increasing use of performance specifications and alternative project delivery methods that shift more responsibility for quality management to industry.
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Introduction 7 The objectives of the survey were to: • Identify trends related to materials QA, • Identify different ways DOTs identify, assess, and mitigate quality-related risk, • Obtain general data related to QA costs and probability of failure (non-conformance) , • Assess state DOT materials management systems, • Identify possible candidates for subsequent in-depth interviews, and • Identify what additional information would have to be collected through the interviews.
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8Literature Review The first research task involved a comprehensive literature review to capture the state-ofthe-practice of materials QA in the highway construction industry. Complete details regarding the approach taken to this literature review are provided below, followed by a summary and critique of the documents collected.
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Literature review 9 highway construction projects on the National Highway System conform to the requirements of the approved plans and specifications. Various documents, including FHWA HRT-12-039, further describe a comprehensive QA program as consisting of the following core elements: quality control, acceptance, independent assurance, dispute resolution, personnel qualification, and laboratory accreditation/qualification.
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10 Guidelines for Optimizing the risk and Cost of Materials Qa programs – Criticality of specific materials or products from the perspective of difficulty to repair or replace, safety, maintenance cost, or cost of rework; and – Project characteristics, such as type, size, and complexity (Generally foundation materials, pavements, and structures represent the most critical assets and involve a commensurate investment in materials QA.)
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Literature review 11 materials, a high level of testing and inspection is often required or anticipated to control variability or assure performance. FHWA QA Requirements and Use of Contractor Testing Federal requirements can also heavily influence a DOT's QA practices, particularly those used for acceptance.
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12 Guidelines for Optimizing the risk and Cost of Materials Qa programs and testing to be able to identify statistically valid differences between its results and those of the contractor. [The F-test (comparison of variances)
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Literature review 13 Table 2.1. Summary of state practices reviewed.
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Table 2.1. (Continued)
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Literature review 15 vary from very specific sources, such as a mill test report for a specific lot of material (issued by the fabricator or producer of the raw materials) , to very general sources (such as a contractor's certification that the materials were obtained from a reputable source of supply)
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16 Guidelines for Optimizing the risk and Cost of Materials Qa programs Other considerations that the project engineer may factor into its decision to use small quantity acceptance include whether or not: – The material has been previously approved, – The material is certified, – A mix design or reference mix design is available, – The material has been recently tested with satisfactory results, and – The material is structurally significant. Small quantity acceptance may also be used for any quantity of the following: – Curbs and sidewalks, – Driveways and road approaches, – Paved ditches and slopes, and – Packaged concrete meeting ASTM C387 used for jobsite mixing.
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Literature review 17 Certification. DOTs also accept certain materials by certification.
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18 Guidelines for Optimizing the risk and Cost of Materials Qa programs Figure 2.1. Example organizational structure for QA management on a design-build project [adapted from TxDOT, 2011]
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Literature review 19 Optimization Strategies The literature contains some examples of formal attempts by DOTs to explicitly create tiered or risk-based materials QA systems. Although these efforts are largely qualitative in nature, they suggest that a solid foundation exists for developing and implementing a more in-depth process for optimizing the costs and risks of materials QA, as contemplated under this research project.
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20 Guidelines for Optimizing the risk and Cost of Materials Qa programs Table 2.5. Caltrans specification sections with associated tier levels.
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Literature review 21 Table 2.5. (Continued)
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22 Guidelines for Optimizing the risk and Cost of Materials Qa programs has suggested with regard to QA practices in general)
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Literature review 23 Construction Activity Priority Macro-Consequences Due to Missed/Reduced Inspection Critical Items to Be Watched Frequency of Inspection Clearing site Low Areas to and not to be cleared Randomly -- -Clearing obstructions Randomly Removal to adequate depth Randomly Identify wet spots Randomly Aggregate base course High Functional failures, increased maintenance costs, decreased design life Moisture and density control Frequently Compactor passes Constantly Depth of each lift Constantly Documentation Constantly Obtain tickets for materials (depending on payment method) Frequently Embankment High Functional failures, increased maintenance costs, decreased design life Quality of the soil being placed Constantly Moisture content Constantly Density Constantly Measure embankment area Constantly Lifts height and width Frequently [Source: Mostafavi and Abraham, 2012]
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24 Guidelines for Optimizing the risk and Cost of Materials Qa programs developed a conceptual internal ranking of QA acceptance practices, ranging from the most intensive level of scrutiny to the least intensive as follows: • Level 1. Highest level: WSDOT acceptance testing, or a combination of fabrication inspection coupled with a requirement for a manufacturer's quality system plan (an example would be structural steel)
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Literature review 25 the ability of individual material properties to act as indicators of performance. This analysis of material properties was then used as a basis for determining how much owner verification testing should be performed to validate contractor test results used in the acceptance decision (TxDOT, 2011)
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26 Guidelines for Optimizing the risk and Cost of Materials Qa programs past the contractual maintenance obligations. Under the Level 3 approach, OV does not perform tests but observes the QA test performance for equipment and procedural compliance with the test procedure.
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Literature review 27 department documents and the departments verification sampling and testing frequencies should be a minimum of 25% of the QC testing frequency. Acceptance is based upon both validation of statistical analysis of complimentary QC test data population and QA verification test data populations and both test results meeting acceptable material acceptance limits as defined in the contract documents.
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Specification Section Risk Factor, applications, and hold points (as appropriate) Quality Assurance Actions and Testing 201: Clearing and Grubbing RF-3: All work Materials QA: N/A CI QA: random verification of QC records for work documented as progressed, verify adherence to work limits, and compliance with planned/required protection/restoration.
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Literature review 29 Theoretically, the cost of improving QA will continue to rise while the cost of failure continues to fall, suggesting the existence of an optimum QA investment point at which the sum of the cost of materials QA and the cost of failure are at a minimum. This would yield the lowest total cost to achieve the desired level of quality.
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30 Data Collection To expand on the trends identified in the literature and ensure adequate input from a diverse cross section of DOTs, two data collection approaches were used: a survey and individual interviews. The surveys were used as an initial screening and interest gathering tool designed to reach the broadest group of materials and construction engineers in the shortest time.
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Data Collection 31 To minimize the time and effort of respondents and help ensure an adequate response rate, the following best practices were incorporated into the design and deployment of the survey: • Use of clear, relatively short, non-leading survey questions that asked respondents to rate, rank, and/or select the best response(s) from a list of provided choices as well as the option to provide additional comments in open-ended dialog boxes; • Invitations for the respondents to self-select for further participation in the research and to share examples of their QA documents; • Inclusion of an endorsement letter from the chairman of the AASHTO Subcommittee on Materials stressing the importance of the study and the need for survey participation; • Periodic reminders sent to non-respondents; and • Automated data collection and aggregation to reduce the possibility of manual tabulation or interpretation errors.
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32 Guidelines for Optimizing the risk and Cost of Materials Qa programs Optimization Strategies (Tiered and Risk-Based) The survey results confirmed a key finding from the literature assessment that several agencies "optimize" their materials acceptance practices to some degree (whether formally or informally)
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Data Collection 33 Some of the respondents also commented that use of QC data for acceptance is more typical of design-build or alternative project delivery projects. Alternative Project Delivery Methods The contract documents reviewed as part of the literature review suggested that use of designbuild and other alternative project delivery methods may change the "traditional" approach to materials QA by shifting greater responsibility for quality to industry.
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34 Guidelines for Optimizing the risk and Cost of Materials Qa programs entailed determining how QA costs are allocated within agency construction programs and which materials represent the most critical assets requiring a commensurate investment in QA. Similarly, the team attempted to extract information related to the percentage of defective (or non-conforming)
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Data Collection 35 • Materials qualification and certification practices; • Experience with alternative delivery and warranty/guarantee provisions; • Structured approach to material QA/acceptance based on material type (project-produced, plant-produced, and standard manufactured products) , project types, and other risk factors; and • Availability of previous FHWA or internal QA process reviews or audits.
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36 Guidelines for Optimizing the risk and Cost of Materials Qa programs • Use of preapproved products and materials or QPLs and relationship to materials QA; • Identification of significant materials/product risks and likelihood and consequences (cost or other) of non-compliance with specification requirements; and • Use of any emerging or advanced testing or certification methods.
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Data Collection 37 1. Reduced frequency of testing for small quantities and large volumes of projectproduced materials under control.
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38 Guidelines for Optimizing the risk and Cost of Materials Qa programs During the interview itself, Caltrans explained that the key to achieving this balance is to relate testing frequency to the rate and consistency of production. If the production tends to be continuous and consistent, the testing frequency may be lower than that used if there are multiple interruptions.
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Data Collection 39 tier level listing is based on the consequence of failure of each item. Tier Level 1 items are considered to have the greatest consequence of failure, while Tier Level 4 items have the least consequence.
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40 Guidelines for Optimizing the risk and Cost of Materials Qa programs Caltrans is adopting a risk-based approach to source inspection that shifts more risk and responsibility to suppliers to self-regulate. • NJDOT indicated that it will adjust or cut back on testing or inspection (or audit)
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Data Collection 41 agencies in the mid-Atlantic region could share in the costs of QA plant inspection (e.g., many agencies use the same supplier, Valmont, for sign structures)
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No. Material Type FDOT Material No.
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Data Collection 43 warranty options. TxDOT conducted an initial materials risk workshop related to SH 130 after recognizing that the pace of the project was not conducive to standard TxDOT acceptance testing.
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44 Guidelines for Optimizing the risk and Cost of Materials Qa programs • MDSHA explained that it modifies its standard materials QA processes for design-build megaprojects. For a design-build project, the contractor must prepare and submit for approval a quality management plan (QMP)
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Data Collection 45 Cost of Quality QA Costs and Budgeting of Materials QA (Cost of Conformance)
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46 Guidelines for Optimizing the risk and Cost of Materials Qa programs (including laboratory testing and plant inspections) ranged from 0.4% to 4% of the program budget.
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Data Collection 47 A trend identified through the interview discussions is that is industry is assuming more responsibility for the cost of materials QA through national, regional, or state qualification or certification programs and greater use of contractor QC testing for acceptance. Most of the DOTs interviewed believe that this trend will continue as DOTs continue to downsize their inspection and testing staff while maintaining or increasing the size of their projects or programs.
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48 Guidelines for Optimizing the risk and Cost of Materials Qa programs • Some DOTs have developed processes to incorporate risk considerations in their materials QA practices. This is essentially an extension of DOT efforts to tier materials QA based on the criticality of materials by applying a more formal framework for risk rating materials.
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49 Optimization Model Model Overview As discussed in Chapter 2, the conceptual foundation for analyzing the economics of quality is well established. Theoretically, if prevention, appraisal, and failure costs are measured and tracked, it is possible to determine an optimum QA investment point at which the total cost of quality (i.e., the sum of the cost of conformance and the cost of failure)
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50 Guidelines for Optimizing the risk and Cost of Materials Qa programs similar in concept to the processes used by WSDOT and Caltrans to risk rank materials, as described in Chapter 2. • Level 2 has a narrower focus, attempting to optimize acceptance testing by emphasizing properties and test methods that are more direct indicators of performance.
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Optimization Model 51 Level 1 Level 2 Level 3 Objective Adjust QA effort (e.g., greater reliance on certification and inspection) based on qualitative assessment of the risk of material failure Adjust owner QA testing effort based on material property importance and risk Obtain the optimal QA investment point based on an explicit consideration of the cost of QA versus the cost of non-conformance Inputs • Materials of interest • Standard acceptance plans • Expert judgment regarding material risk • Standard acceptance plans • Primary and secondary properties and test methods • Traditional and advanced properties and test methods • Expert judgment regarding material risk • Cost to implement different levels of QA (testing, inspection, certification)
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52 Guidelines for Optimizing the risk and Cost of Materials Qa programs Step 1: Identify materials of interest. Step 2: Assess the risk of non-conformance for each material of interest.
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Optimization Model 53 Step 2: Review existing acceptance plan. Step 3: Evaluate importance of acceptance properties as indicators of performance.
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54 Guidelines for Optimizing the risk and Cost of Materials Qa programs Step 4: Quantify the costs of QA. Step 2: Identify project factors that may influence QA effort.
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55 Conclusions Summary of Research Findings The literature review and data collection efforts provided insight into materials QA principles and processes, and clarified how, and to what extent, these practices can be optimized on the basis of risk and cost within the transportation construction industry. A synthesis of these findings, as summarized below, guided the research team in developing the optimization process introduced in Chapter 4 and presented in detail in the accompanying "Guidelines." • Program Variability and the Need for a Flexible Model.
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56 Guidelines for Optimizing the risk and Cost of Materials Qa programs well established in the literature. However, the literature also suggested that real world application of quality cost calculations is quite uncommon, largely due to practical difficulties in identifying and tracking all of the necessary cost inputs.
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Conclusions 57 Additional Research into the Costs of Quality for Transportation Construction Projects Practical application of a cost-based optimization model for materials QA requires reliable, accurate, and complete information regarding the total cost of quality over the course of a material's lifecycle. The total cost of quality includes both the cost of conformance (prevention and appraisal)
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58 Guidelines for Optimizing the risk and Cost of Materials Qa programs to evaluate specific non-traditional or advanced test methods. These evaluations should also consider the total cost of quality in the cost/benefit analysis (i.e., the cost of QA plus cost of non-conformance)
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59 References AASHTO.
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60 Guidelines for Optimizing the Risk and Cost of Materials QA Programs Juran, J
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61 • American Association of Highway and Transportation Officials.
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62 Guidelines for Optimizing the Risk and Cost of Materials QA programs • California Department of Transportation.
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Annotated Bibliography 63 contractor test data. Without these controls, the risks of accepting non-conforming materials are higher.
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64 Guidelines for Optimizing the Risk and Cost of Materials QA programs • Goulias, D., Karimi, S January 22, 2013.
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Annotated Bibliography 65 – This memorandum establishes a procedure of acceptance of a certain production source in Illinois through certification or quality control program. • Illinois Department of Transportation.
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66 Guidelines for Optimizing the Risk and Cost of Materials QA programs quality costs. To provide more action-oriented information, some organizations are using root-cause analysis to link quality costs to specific activities.
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Annotated Bibliography 67 • Schiffauerova, A., and Thomson, V
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68 Guidelines for Optimizing the Risk and Cost of Materials QA programs included placing more emphasis on properties known to affect durability and long-term performance, using test methods that would be more conducive to rapid, continuous sampling and testing, reducing the risk of incorrect acceptance decisions, and allowing for reduced verification or agency oversight. • Texas Department of Transportation.
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Annotated Bibliography 69 misunderstood, or generally confusing. It provides some diagrams as well to exemplify QA system elements or to detail accountability for quality, sampling or performance.
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70 Guidelines for Optimizing the Risk and Cost of Materials QA programs allocation to provide the lowest final cost to the State's transportation needs. Finally it provides the acceptance procedures and statistics.
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71 A p p e n d i x B Definitions B.1 Quality Assurance Terms Acceptance: the agency's process of determining whether or not to accept or reject a product (If contractor test results are used to support the acceptance decision, the agency's acceptance process includes contractor testing, agency verification and validation, and possibly dispute resolution)
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72 Guidelines for Optimizing the Risk and Cost of Materials QA programs Design-build: a project delivery system in which an entity provides both design and construction services under a single contract. Public-Private-Partnership/Concessionaire: a project delivery system where an entity or a developer invests in a project and provides financing and integrated services to design, construct, operate, and maintain a roadway or transportation facility in return for tolls or some other compensation under the operating or concession agreement.
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73 A p p e n d i x C Survey Results Respondent Contact Information: Agency Name: Position/Title: Alabama Department of Transportation Assistant Materials and Tests Engineer Alabama Department of Transportation Bureau of Materials and Tests Testing Engineer Arizona DOT Materials Group - Quality Assurance Manager Arkansas State Highway and Transportation Department Materials Engineer California Department of Transportation Senior Bridge Engineer Caltrans District Material Engineer Caltrans ConnDOT Principal Engineer Materials Delaware Department of Transportation Chief Materials & Research Engineer Florida DOT Director, Office of Materials GDOT Testing Bureau Chief Illinois Tollway Deputy Program Manager of Materials Indiana Department of Transportation Manager Iowa DOT Materials Testing Engineer KSDOT Chief, Bureau of Research KY Transportation Cabinet Director, Division of Materials LADOTD Materials Engineer Maine Department of Transportation Director, Materials Testing and Exploration MassDOT Civil Engineer Materials MD State Highway Admin. Division Chief, Materials Management Michigan Department of Transportation Concrete Operation and Materials Engineer Mississippi Department of Transportation Assistant Chief Engineer - Operations
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74 Guidelines for Optimizing the Risk and Cost of Materials QA programs Agency Name: Position/Title: Montana DOT Testing Engineer MTO Head, Bituminous Section NC DOT State Materials Engineer Nebraska Department of Roads State Construction Engineer New Mexico Department of Transportation Materials/Testing Engineer NJDOT Manager, Bureau of Materials NYSDOT CE3 - Concrete Program Manager Ohio DOT Administrator, Office of Construction Management Ohio DOT Structural Welding Engineer Ohio DOT Administrator, Office of Materials Management Oklahoma DOT Assistant Materials and Research Engineer Oregon DOT Quality Assurance Engineer PennDOT Chief Chemist PennDOT Construction Quality Assurance Section Chief Peoples State Materials Engineer PORT AUTHORITY OF NEW YORK & NEW JERSEY CHIEF OF MATERIALS ENGINEERING Rhode Island Department of Transportation Associate Chief Engineer Roads Maritime Services NSW Australia Manager Delivery Strategy South Carolina DOT Quality Assurance Engineer Teichert Materials Q/A Supervisor Texas DOT Deputy Director, Construction Division TN Department of Transportation C.E. Manager II Utah DOT State Materials Engineer Virginia Department of Transportation State Materials Engineer Virginia DOT Assistant State Materials Engineer Washington State DOT State Materials Engineer Wisconsin Department of Transportation Quality Management Program Engineer WisDOT Materials Lab Supervisor Missouri DOT Physical Laboratory Director Missouri DOT Construction and Materials Liaison Engineer
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Survey Results 75 1. Please select any of the following characteristics that your agency uses to determine the materials acceptance procedures and protocols for a project (please select all that apply)
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76 Guidelines for Optimizing the Risk and Cost of Materials QA programs 2. Please select any materials management and tracking systems used in your agency for statewide materials management and for defining project materials QA requirements?
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Survey Results 77 3. Questions 3.1 and 3.2 ask how your agency typically accepts materials for high (3.1)
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78 Guidelines for Optimizing the Risk and Cost of Materials QA programs 3.1. Certification # Question Always Sometimes Never Total Responses 1 Earthwork 4 6 21 31 2 Base Courses 10 3 21 34 3 Pavements 11 8 15 34 4 CIP Structures 14 10 11 35 7 Precast modular decks, pavement 16 12 6 34 8 Precast concrete structures 22 17 3 42 9 Structural Steel 34 4 4 42 12 Paints and coatings 26 12 5 43 13 Traffic control devices 28 12 1 41 16 Geosynthetics 34 8 3 45 17 Standard steel shapes or products 32 7 3 42 18 Other project produced 4 19 7 30 19 Other fabricated/plant produced 20 16 1 37 20 Other Standard Manufactured Materials/Products 21 19 0 40
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Survey Results 79 3.1. Inspection # Question Always Sometimes Never Total Responses Mean 1 Earthwork 37 5 0 42 1.12 2 Base Courses 37 5 0 42 1.12 3 Pavements 36 6 0 42 1.14 4 CIP Structures 37 4 0 41 1.10 7 Precast modular decks, pavement 27 10 2 39 1.36 8 Precast concrete structures 31 13 0 44 1.30 9 Structural Steel 37 6 2 45 1.22 12 Paints and coatings 23 16 2 41 1.49 13 Traffic control devices 16 18 3 37 1.65 16 Geosynthetics 16 17 5 38 1.71 17 Standard steel shapes or products 13 16 7 36 1.83 18 Other project produced 16 17 1 34 1.56 19 Other fabricated/plant produced 17 22 0 39 1.56 20 Other Standard Manufactured Materials/Products 8 23 5 36 1.92
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80 Guidelines for Optimizing the Risk and Cost of Materials QA programs 3.1. Addional comments (OH)
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Survey Results 81 3.2. Sampling and testing # Question Always Sometimes Never Total Responses 1 Earthwork 28 14 2 44 2 Base Courses 27 15 1 43 3 Pavements 28 16 0 44 4 CIP Structures 28 13 0 41 7 Precast modular decks, pavement 20 13 2 35 8 Precast concrete structures 18 17 2 37 9 Structural Steel 14 15 8 37 12 Paints and coatings 8 21 5 34 13 Traffic control devices 1 16 14 31 16 Geosynthetics 1 25 10 36 17 Standard steel shapes or products 4 16 11 31 18 Other project produced 8 27 2 37 19 Other fabricated/plant produced 3 29 1 33 20 Other Standard Manufactured Materials/Products 0 29 3 32
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82 Guidelines for Optimizing the Risk and Cost of Materials QA programs 3.2. Certification # Question Always Sometimes Never Total Responses 1 Earthwork 4 7 22 33 2 Base Courses 10 6 18 34 3 Pavements 12 9 13 34 4 CIP Structures 11 10 11 32 7 Precast modular decks, pavement 16 9 7 32 8 Precast concrete structures 23 12 4 39 9 Structural Steel 29 4 5 38 12 Paints and coatings 25 14 3 42 13 Traffic control devices 27 9 1 37 16 Geosynthetics 29 8 4 41 17 Standard steel shapes or products 30 10 2 42 18 Other project produced 5 20 7 32 19 Other fabricated/plant produced 18 17 1 36 20 Other Standard Manufactured Materials/Products 19 21 0 40
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Survey Results 83 3.2. Inspection # Question Always Sometimes Never Total Responses 1 Earthwork 28 13 0 41 2 Base Courses 28 13 0 41 3 Pavements 30 11 0 41 4 CIP Structures 32 7 0 39 7 Precast modular decks, pavement 28 7 2 37 8 Precast concrete structures 23 16 1 40 9 Structural Steel 29 9 2 40 12 Paints and coatings 18 16 3 37 13 Traffic control devices 13 17 3 33 16 Geosynthetics 11 18 5 34 17 Standard steel shapes or products 10 17 7 34 18 Other project produced 12 22 1 35 19 Other fabricated/plant produced 12 25 0 37 20 Other Standard Manufactured Materials/Products 5 25 5 35
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84 Guidelines for Optimizing the Risk and Cost of Materials QA programs 3.2. Additional comments (MT)
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Survey Results 85 4. Please indicate whether statistically-based specifications using random sampling and lot-by-lot testing, and payment adjustment systems are used in your materials QA program?
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86 Guidelines for Optimizing the Risk and Cost of Materials QA programs 5. Do you utilize contractor QC data in the acceptance decision?
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Survey Results 87 6. Does your agency use alternative project delivery methods (e.g.
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88 Guidelines for Optimizing the Risk and Cost of Materials QA programs 6.2. Do project delivery methods alter your standard procedure for materials QA?
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Survey Results 89 Question 7 Comments: Yes (please describe the program)
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90 Guidelines for Optimizing the Risk and Cost of Materials QA programs 9. Do you or any of your qualified producers/suppliers maintain a database of QA costs?
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Survey Results 91 14. Please identify if there are other individuals within your agency or other outside organization that would have an interest in this research and would have anything to share.
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92 Questionnaire NCHRP 10-92, Optimizing the Risks and Cost of Materials QA Programs Interview Form – DOT State: Contact Information: Review Team: Date: Discussion Point Objective A General Information Understand DOT organizational structure for materials QA Understand how materials QA is internally managed Understand how industry affects materials QA practices Identify materials QA manuals and guidelines Identify qualifications requirements for lab and technician staff Identify and understand automated systems for materials management Discussion Topics: 1.
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interview Questionnaire 93 Optimizing the Risk and Cost of Materials QA Programs Discussion Point Objective B Materials Acceptance Hierarchy and Categories Identify the range of materials QA acceptance practices and standard criteria for determining materials QA acceptance methods 1.
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94 Guidelines for Optimizing the Risk and Cost of Materials QA programs Optimizing the Risk and Cost of Materials QA Programs : Discussion Point Objective C Materials QA Acceptance Criteria Identify criteria that modify standard materials QA acceptance practices 1.
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interview Questionnaire 95 Optimizing the Risk and Cost of Materials QA Programs Discussion Point Objective D Materials QA Risk Assess the risk of materials and how the risks might affect the level of materials QA and associated internal (and external)
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96 Guidelines for Optimizing the Risk and Cost of Materials QA programs Optimizing the Risk and Cost of Materials QA Programs Discussion Point Objective E Criteria for QA sampling and testing of projectproduced materials/products Identify the key properties for project-produced materials QA sampling and testing for acceptance, and what criteria may modify QA acceptance 1.
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interview Questionnaire 97 Optimizing the Risk and Cost of Materials QA Programs Discussion Point Objective Strength (compressive/flexural) Cylinders/Beams (Maturity Method)
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98 Guidelines for Optimizing the Risk and Cost of Materials QA programs Optimizing the Risk and Cost of Materials QA Programs Discussion Point Objective F Alignment of DOT materials QA acceptance with 23 CFR 637 Identify how 23 CFR 637 is implemented and whether contractor/producer QC test results are utilized for acceptance 1.
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interview Questionnaire 99 Optimizing the Risk and Cost of Materials QA Programs Discussion Point Objective G Criteria for Materials QA Acceptance of fabricated materials by certification and/or other methods Identify key criteria used to accept plant-produced or fabricated materials by certification or other methods and what criteria may modify QA acceptance for plant-produced or prefabricated materials.
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100 Guidelines for Optimizing the Risk and Cost of Materials QA programs Optimizing the Risk and Cost of Materials QA Programs Discussion Point Objective H Criteria for Materials QA Acceptance of Standard Manufactured Products Identify key criteria that may modify QA acceptance practices for standard manufactured products Discussion Topics: 1.
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interview Questionnaire 101 Discussion Point Objective I Materials QA Cost Assess the relative cost of materials and the associated internal (and external)
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102 Guidelines for Optimizing the Risk and Cost of Materials QA programs List of Abbreviations and Terms ACI: American Concrete Institute AASHTO: American Association of State Highway and Transportation Officials Acceptance: All factors used by the Agency (i.e., sampling, testing, and inspection) to evaluate the degree of compliance with Contract requirements and to determine the corresponding value for a given product [FHWA-NHI-08-067]
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interview Questionnaire 103 ISO 9001: The international organization for standardization, ISO, standard 9001 sets out the criteria for a quality management system including requirements for certification. Many organizations (e.g., producers and suppliers)
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104 Guidelines for Optimizing the Risk and Cost of Materials QA programs SHA: State Highway Agency SME: State Materials Engineer Standard Manufactured Materials: Standard items are produced routinely (i.e., not for a specific project) by a manufacturer.
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105 A p p e n d i x e State Interview Summary State/Contact Information Interview Summary Florida (FDOT) Timothy J
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106 Guidelines for Optimizing the Risk and Cost of Materials QA programs • For example, for the I- 4 Ultimate P3 Project: QC and QA may be reduced if 10 consecutive tests are OK (performance-based frequency reduction) • Because structural concrete outlives the Concession Agreement, frequency of testing is reduced FDOT uses a standard 3-year asphalt pavement warranty specification • No bonding required, FDOT uses a "guarantee" approach (prequalification for future work contingent on meeting warranty requirements)
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State interview Summary 107 State/Contact Information Interview Summary California (Caltrans) 5/21-22/14 John Babcock HQ Office Chief Daniel Speer METS-OSM Office Chief Jnex Youch Senior Bridge Engineer Bobby Petska CT MET OSM John Cammers CT-DES-SC Keith Hoffman CT-DES-METS Jim Sagar CT-DES-METS/GS Ken Darby CT-DOC-OCE Chris Cummings CT-NR-CONST Robert Sto
CT-DES-SC Jose G
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108 Guidelines for Optimizing the Risk and Cost of Materials QA programs State/Contact Information Interview Summary Changing Materials QA Requirements New materials requirements are being introduced for recycled materials (asphalt and concrete) with new RAP mixes for both and specs based on volume of asphalt.
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State interview Summary 109 State/Contact Information Interview Summary Cost of QA Cost of QA includes the costs of testing, inspection, and administration. From a lab perspective, a materials testing estimate is required including # of testing hours.
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110 Guidelines for Optimizing the Risk and Cost of Materials QA programs State/Contact Information Interview Summary Caltrans Materials/Construction QA Optimization Initiatives A Risk-based Method for Acceptance based on Project/Materials Type.
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State interview Summary 111 State/Contact Information Interview Summary Washington DOT (WSDOT) 5/21/14 Kurt Williams State Materials Engineer 6/13/14 Jeff Carpenter State Construction Engineer WSDOT undertook a Materials Risk Analysis between 2002 and 2005 with the final report published in February 2010.
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State/Contact Information Interview Summary Ohio (ODOT) Jeff Chandler Structural Welding Engineer Office of Materials Management 5/13/14 Organization ODOTs Division of CM includes the offices of Materials Management and Construction Management Materials Management includes a CFR accredited Central Lab and District Labs that handle acceptance of materials.
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State interview Summary 113 State/Contact Information Interview Summary New Jersey (NJDOT) Eileen C
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114 Guidelines for Optimizing the Risk and Cost of Materials QA programs Certification TXDOT certifies std. manufactured materials (i.e.
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State interview Summary 115 State/Contact Information Interview Summary Current TXDOT Optimization strategies The TXDOT Guide Schedule of Sampling and Testing provides the basis of their requirements. This document was revised based on the findings of a research effort that was completed in 2001 (project 1781)
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116 Guidelines for Optimizing the Risk and Cost of Materials QA programs State/Contact Information Interview Summary After that experience of increased verification testing because of the number of tests run by the contracting firm, the process was modified to develop a tiered system and recommended levels, based on risk. Level 1 (highest level is currently soils, pavements, and structures)
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State interview Summary 117 State/Contact Information Interview Summary Virginia (VDOT) 5/28/14 William R
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118 Guidelines for Optimizing the Risk and Cost of Materials QA programs State/Contact Information Interview Summary Maryland State Highway Administration (MDSHA) 6/12/14, 9/25/14 Woodrow Hood Division Chief, Materials Management Office of Materials Technology MDSHA maintains a standard frequency guide for minimum testing frequencies which varies based on the criticality of the project (i.e.
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State interview Summary 119 State/Contact Information Interview Summary WB account includes test costs plus a correction factor spread out over all projects. SHA is experimenting with new roadway compaction criteria (intelligent compaction)
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120 A p p e n d i x F Demonstration of Level 3 Optimization Process Level 3 Model Overview As shown in Figure F.1 -- which provides a theoretical representation of the QA optimization for a given material -- the optimal QA investment point is that which minimizes the total cost of quality. The total cost of quality can be defined as the sum of the total investment in material QA and the expected value of a defect.
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demonstration of Level 3 Optimization process 121 in this study, Delphi is also particularly useful when the research problem does not lend itself to precise analytical techniques but can benefit from subjective judgments on a collective basis; the individuals needed to contribute to the examination of a broad or complex problem have no history of adequate communication and may represent diverse backgrounds; time and cost constraints make frequent group meetings infeasible; more individuals are needed than can effectively interact in a face-to-face meeting; and the heterogeneity of the participants must be preserved to assure the validity of the results (Linstone and Turoff 2002; Chapman 1998)
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122 Guidelines for Optimizing the Risk and Cost of Materials QA programs In order to collect data from the panel, we followed the steps indicated in Figure F.2. To facilitate this effort, we developed a survey tool using Google Sheets, a web-based spreadsheet application similar to Microsoft Excel, which allowed all panelists to input their responses into the same document and thus streamline the processing of the expert opinions.
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demonstration of Level 3 Optimization process 123 Step 2: Identify Project Factors that Influence QA Effort and Develop Representative Scenarios The results of the literature review, survey, and interviews all suggested that certain factors can influence the QA practices applied to a specific project. For example, the Florida DOT allows for reductions in the frequency of QA testing of structural concrete, excavation and embankment, and pavement by 50% when 12 or more QC tests are confirmed to be within tolerance.
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124 Guidelines for Optimizing the Risk and Cost of Materials QA programs Table F.3 summarizes the levels of QA that were explored by the Delphi experts empaneled for HMA. These levels are expected to vary with different materials and properties.
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demonstration of Level 3 Optimization process 125 a typical defect associated with each HMA property of interest. The goal of this step was to build the expected value of non-conformance for each given QA level of effort.
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126 Guidelines for Optimizing the Risk and Cost of Materials QA programs 0.00% 10.00% 20.00% 30.00% 40.00% 50.00% 60.00% 70.00% 80.00% L E V E L 1 L E V E L 2 L E V E L 3 L E V E L 4 L E V E L 5 P ER CE N TA G E O F M AT ER IA L CO ST LEVEL OF QUALITY ASSURANCE EFFORT EV of non-conformance Cost of QA CoQ Figure F.5. CoQ curves.
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demonstration of Level 3 Optimization process 127 The probability of a non-conforming material was the variable with the highest variability. For example, for Scenario 4, Density's Level 2 of QA effort (visual inspection)
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128 Guidelines for Optimizing the Risk and Cost of Materials QA programs 0% 20% 40% 60% 80% 100% 120% Level 1 Level 2 Level 3 Level 4 Level 5 Pr ob ab ili ty o f a n on -c on fo rm in g m at er ia l Quality assurance effort Density-Scenario 1 0% 20% 40% 60% 80% 100% 120% Level 1 Level 2 Level 3 Level 4 Level 5 Pr ob ab ili ty o f a n on -c on fo rm in g m at er ia l Quality assurance effort Density-Scenario 2 0% 20% 40% 60% 80% 100% 120% Level 1 Level 2 Level 3 Level 4 Level 5 Pr ob ab ili ty o f a n on -c on fo rm in g m at er ia l Quality assurance effort Density-Scenario 3 0% 20% 40% 60% 80% 100% 120% Level 1 Level 2 Level 3 Level 4 Level 5P ro ba bi lit y of a n on -c on fo rm in g m at er ia l Quality assurance effort Density-Scenario 4 Figure F.6. Probability of non-conforming material Delphi results for density.
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demonstration of Level 3 Optimization process 129 0.00% 10.00% 20.00% 30.00% 40.00% 50.00% 60.00% 70.00% 80.00% L E V E L 1 L E V E L 2 L E V E L 3 L E V E L 4 L E V E L 5 EV of non-conformance Cost of QA CoQ Figure F.7. Cost of Quality optimization for HMA using density in Scenario 4.
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130 Guidelines for Optimizing the Risk and Cost of Materials QA programs 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% L E V E L 1 L E V E L 2 L E V E L 3 L E V E L 4 L E V E L 5 % O F M A TE RI A L CO ST QA EFFORT LEVEL DENSITY COQ Scenario 1 Scenario 2 Scenario 3 Scenario 4 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% L E V E L 1 L E V E L 2 L E V E L 3 L E V E L 4 L E V E L 5 % O F M AT ER IA L CO ST QA EFFORT LEVEL GRADATION COQ Scenario 1 Scenario 2 Scenario 3 Scenario 4 0% 20% 40% 60% 80% 100% 120% L E V E L 1 L E V E L 2 L E V E L 3 L E V E L 4 L E V E L 5 % O F M A TE RI A L CO ST QA EFFORT LEVEL ASPHALT CONTENT COQ Scenario 1 Scenario 2 Scenario 3 Scenario 4 Figure F.8. Optimization curves.
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demonstration of Level 3 Optimization process 131 DENSITY 0% 20% 40% 60% 80% 100% L E V E L 1 L E V E L 2 L E V E L 3 L E V E L 4 L E V E L 5 PR O BA BI LI TY O F A N O N -C O N FO RM IN G M A TE RI A L QA LEVEL OF EFFORT Scenario 1 Scenario 2 Scenario 3 Scenario 4 ASPHALT CONTENT 0% 20% 40% 60% 80% 100% L E V E L 1 L E V E L 2 L E V E L 3 L E V E L 4 L E V E L 5 PR O BA BI LI TY O F A N O N -C O N FO RM IN G M A TE RI A L QA LEVEL OF EFFORT Scenario 1 Scenario 2 Scenario 3 Scenario 4 GRADATION 0% 20% 40% 60% 80% 100% L E V E L 1 L E V E L 2 L E V E L 3 L E V E L 4 L E V E L 5 PR O BA BI LI TY O F A N O N -C O N FO RM IN G M A TE RI A L QA LEVEL OF EFFORT Scenario 1 Scenario 2 Scenario 3 Scenario 4 Figure F.9. Probability of non-conformance vs.
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Key Terms
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