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89 A p p e n d i x F Summary of preliminary Survey A questionnaire (see Table F.1) was sent to the SHRP 2 coordi- nators in all 50 states. This was the first action. Sixteen SHAs responded to the questionnaire. It contained a series of questions regarding three funda- mental issues: ⢠What materials are the most challenging regarding their quality control in the field? ⢠What analytical procedures are currently used in the state agencies? ⢠What testing constraints are common under field conditions, and what features of the quality assurance/quality control (QA/QC) procedures and related devices are desirable to address these requirements? Figures F.1 through F.4 present a summary of findings from the questionnaire. It can be concluded that some department of transportation (DOT) agencies are familiar with spectroscopy methods, that asphalt- and cement-related materials and paints are the most challenging in terms of QA/QC, and finally that time, training and, costs are the biggest concerns when imple- menting new procedures. Summary of Workshop The second action was to organize a workshop with several experts in materials and construction from both industry and transportation agencies. Before the workshop, all participants received the same questionnaire as the SHRP 2 coordinators and a short up-to-date summary of findings. The workshop took place at the University of Connecticut on May 6, 2009. Table F.2 lists the industries and government agencies of the participants. Table F.3 presents a summary of findings from the question- naire and the workshop. On the basis of the responses and the discussion during the workshop, the following comments can be made: ⢠Materials and construction professionals were concerned that spectroscopy devices require extensive training in prep- aration for testing and interpreting their results. State repre- sentatives were also concerned about budget restrictions hindering their ability to provide the necessary extra train- ing activities and about the qualification of their personnel. ⢠Current specifications for many construction materials are based on their mechanical performance in the lab or field testing. The participants were concerned that, in order to successfully implement spectroscopy methods, AASHTO procedures must be developed and adopted by the DOTs in their QA/QC specifications. ⢠Correct timing of QA/QC testing during the construction process is very important. The timing depends on several factors, including what material is tested, whether the test- ing is done on the components or the mix, the amount of material and the importance of the job, who is performing the testing (DOT or contractor), and the construction sequence (if timing is too late, then tons of materials will be wasted or lost). ⢠Equipment cost must be justified by its capabilities because most practitioners do not foresee an everyday use of spectroscopic techniques. They envision spectroscopy devices as potentially applicable to larger construction jobs if the quality of the materials is in question. Some profes- sionals, however, mentioned that if the device is highly reliable and accurate, the cost could be offset by poten- tial savings in ensuring the quality and durability of the materials. ⢠Several participants expressed the need for checking the physical parameters of materials (such as air content and aggregate gradation). To the best knowledge of the research team, this cannot be directly achieved by spectroscopy Summary of Preliminary Survey and Workshop (continued on page 93)
90 Table F.1. Summary of Questionnaire for Preliminary Survey and Workshop No. Question Answer 1 What materials or their compounds cause the largest quality control issues? 2 What materials or their compounds are the most crucial for the safety, durability, and reliability of the highway facilities? 3 What materials or their compounds are the most challenging to control in terms of the uniformity during handling and delivery? 4 What analytical procedures for QA/QC of construction materials are you familiar with? 5 What constraints (e.g., time, cost, personnel training) would you place on the analytical QA/QC procedures in the field? 6 How would you rank the importance of the following features for the QA/QC field devices? (5âimportant, 1ânot important): ⢠Accuracy ⢠Precision ⢠Reliability ⢠Speed of testing ⢠Reproducibility ⢠Ease of interpreting the results ⢠Ease of use in the field Figure F.1. Most challenging construction materials in terms of their QA/QC. Portland Cement Concrete Aggregates Asphalt Concrete Traffic Marking Paint Bridge paint Concrete Additives Asphalt Binder Steel Portland Cement Segregation of AC Concrete: entrained air content Pre-packaged Materials Steel Protective Coatings Chloride resistance of PCC Polymer Modified Binders w/c ratio Asphalt emulsion Anchor Bolt Grouts Alkali silica reactivity Organic elements in concrete 302520151050 # of answers Most challenging materials
91 Figure F.2. Analytical QA/QC procedures used in the state agencies. Note: AA = atomic absorption; GC = gas chromatography. XR F FT IR St at ist ica l m et ho ds XR D G ra da tio n AA G C Ex tra ct io n 0 1 2 3 4 5 6 7 8 # of a ns we rs Analytical QA/QC methods known to DOT personnel Time Cost Training Complexity of results Project schedule 0 4 6 8 10 12 142 # of answers Expected challenges in implementing spectroscopy methods for field QA/QC Figure F.3. Challenges in implementing spectroscopy procedures as field QA/QC methods.
92 a cc u ra cy a cc u ra cy a cc u ra cy pr ec isi on pr ec isi on pr ec isi on re lia bi lity re lia bi lity re lia bi litysp ee d of te st in g sp ee d of te st in g sp ee d of te st in g re pr od uc ib ilit y re pr od uc ib ilit y re pr od uc ib ilit y e a se o f i nt er pr et in g th e re su lts e a se o f i nt er pr et in g th e re su lts e a se o f i nt er pr et in g th e re su lts e a se o f u se in th e fie ld c on di tio ns e a se o f u se in th e fie ld c on di tio ns e a se o f u se in th e fie ld c on di tio ns 0 2 4 6 8 10 12 14 16 345 # of re sp on de nt s SCORE 5-very important, 3-less important Desirable features of the QA/QC field methods Figure F.4. Desirable features of the QA/QC methods in the field. Table F.2. Workshop Participants Area of Expertise Industry Government Agency Materials Lafarge North America Cementitious & CKD Projects Manager Connecticut DOT, Division of Research Transportation Engineer Construction Pike Industries, Inc. Corporate Quality Control Manager Tilcon Connecticut Inc. Managers, Asphalt Division New York State DOT Materials Bureau
93 devices. It could potentially be investigated in some larger study. ⢠The physical weight of the field device is important. However, if the device is highly reliable and accurate, then it can be truck-mounted and used during the construction process. ⢠Under no circumstances should developed procedures for spectroscopy methods impose any licensing or security issues. This would create significant obstacles for the success- ful implementation of these procedures. ⢠The qualitative and quantitative requirements for the QA/QC methods in the field were identified during the workshop (Table F.3). These features will be considered in the selection process for specific spectroscopy field devices for Phase 3. Table F.3. Qualitative and Quantitative Requirements for Field QA/QC Methods Featurea Value Accuracy Minimum 1% Goal <0.5% Duration of measurement Maximum 1 h Goal ~5 min Effort involved Maximum 1 person Goal 1 person Amount of prior training Maximum 1 day Goal 0.5 day Reliability Minimum Depends on material (90%) Goal 95% Time to get results Maximum Depends on construction process (1 h) Goal ~5 min Price range Maximum $50,000 Goal <$20,000 Device weight Maximum 50 lb Goal <20 lb Best time for QA/QC? (tank/plant/truck before/after placing?) Maximum Depends on materialb Goal Depends on materialb Sample preparation Maximum Solvent Goal As is a Accuracy: Agreement between a measurement and the true or correct value. Duration of measurement: Time between start and end of testing cycle. Effort involved: Personnel required to perform the test. Amount of prior training: Time required to make personnel familiar with a testing procedure. Reliability: Unlikelihood of equipment failure during the test. Time to get results: Time between beginning of the sample preparation and the end of the analysis of the test results. Price range: Cost of the equipment. Device weight: Mass of the equipment including the case or enclosure. Best time for QA/QC: Stage of the manufacturing and application process when the test is most timely. Sample preparation: Processing and manipulating the material before the test. Minimum/maximum: Acceptable threshold value from the user perspective that given equipment should produce. Goal: Desirable target value from the user perspective that given equipment should produce. b See Tables A.3 and A.4 in Appendix A. (continued from page 89)
