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84 Part 6: FWD Field Testing--Flexible Pavements Question 29: What kind of flexible pavement field testing manual does your agency use? FIGURE B25 Survey response to Question 29: "What kind of flexible pavement field testing manual does your agency use?" Question 30: How much time does a complete flexible pavement network-level FWD testing cycle take? FIGURE B26 Survey response to Question 30: "How much time does a complete flexible pavement network level FWD testing cycle take?"

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85 Question 31: For flexible pavement at the network level, are FWD tests done before the project starts, after the project is com- pleted, or both? FIGURE B27 Survey response to Question 31: "For flexible pavement at the network level, are FWD tests done before the project starts, after the project is completed, or both?" Question 32: For any given flexible pavement project, approximately how soon before the project starts does your agency perform FWD tests? FIGURE B28 Survey response to Question 32: "For any given flexible pavement project, approximately how soon before the project starts does your agency perform FWD tests?"

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86 Question 33: For any given flexible pavement project, approximately how soon after the project is completed does your agency perform FWD tests? FIGURE B29 Survey response to Question 33: "For any given flexible pavement project, approximately how soon after the project is completed does your agency perform FWD tests?" Question 34: Where on flexible pavements are data collected? (Check all that apply.) FIGURE B30 Survey response to Question 34: "Where on flexible pavements are data collected?" (Check all that apply.)

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87 Questions 3538: For each of the following levels, describe your flexible pavement measurement variables, where applicable. Question 35: Project level (including forensics) FIGURE B31 Survey responses to Question 35, Project Level (Including Forensics): "For each of the following levels, describe your flexible pavement measurement variables, where applicable."

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88 TABLE B5 Survey question 35: "For each of the following levels, describe your flexible pavement measurement variables, where applicable." Flexible pavement temperature gradient holes at the project level (including forensics) No. of Temperature Temperature Gradient Temperature Gradient Hole Responding State Gradient Holes Hole Depth(s) Measurement Frequency Alabama 1 Pavement mid-depth 1 min Idaho 1 3 in. 20 min Louisiana 1 1 in. 1 min Nebraska 1 Pavement mid-depth 20 min New Mexico 3 -- -- Pennsylvania 1 1 in. 1 min Texas 2 1 in. 20 min Vermont 1 or 2 Pavement mid-depth 120 min Note: -- = no response given. TABLE B6 Survey question 35: "For each of the following levels, describe your flexible pavement measurement variables, where applicable." Other flexible pavement testing variables at the project level (including forensics) Responding State Other Testing Variables Alabama All projects more than 1 mile in length are tested every two-tenths of a mile. Projects less then 1 mile are tested every tenth of a mile. Alaska No temp gradient holes are done. Air and surface temperatures. California Recorded data for temperature is ambient and pavement surface. Colorado We follow LTPP drop sequence and sensor spacing. Florida Temperatures are only measured for research projects where the bound surface layer needs evaluation. Idaho Temperatures taken at mid-depth of pavement a minimum of once per hour. Indiana Only surface temperature is measured. Iowa Surface temperatures are obtained with the temperature sensor on the FWD unit at time of test. Kansas Varies. Maine We do not use gradient holes. Maryland The drop weights, sequence, etc., are project-specific depending on information required. Michigan Air and surface temperature. Mississippi Temperature of air and surface of the pavement. Montana We use previous day mean temperatures for our temperature correction. No temperature holes are drilled. Nevada We use infrared surface temperatures for gathering temperature data. This measurement is taken at every test location. New Jersey Various LTPP setups (are employed). New York We perform load transfer efficiency tests on PCC joints. North Carolina Asphalt surface temperature is measured at every drop location. Pennsylvania We do not drill any holes for temperatures. Utah We measure surface temperature. Washington Infrared measurement per location and conversion using the bell method.

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89 Question 36: Network level FIGURE B32 Survey responses to Question 36, Network Level: "For each of the following levels, describe your flexible pavement measurement variables, where applicable."

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90 TABLE B7 Survey question 36: "For each of the following levels, describe your flexible pavement measurement variables, where applicable." Flexible pavement temperature gradient holes at the network level Temperature No. of Temperature Gradient Hole Temperature Gradient Hole Responding State Gradient Holes Depth(s) Measurement Frequency New Mexico 3 -- -- Montana 1 1 in. 1 min Texas 1 1 in. 20 min Note: -- = no response given. TABLE B8 Survey question 36: "For each of the following levels, describe your flexible pavement measurement variables, where applicable" Other flexible pavement testing variables at the network level Responding State Other Testing Variables Alaska No temp gradient holes are done. We measure surface and air temperatures. California Network-level testing is not performed. Florida FDOT only evaluates project-level tests, and does not conduct network-level testing. Hawaii Network-level testing is not currently being conducted. Indiana Only surface temperature is measured. Iowa Surface temperatures are obtained with temperature sensor on the FWD unit at test time. Maine We do not use gradient holes. Michigan Surface and air temperature. New Jersey LTPP setups are used. We do not do in-house network Heavy Weight Deflectometer testing. Stantec consulting did some network-level testing for us a few years back. Pennsylvania We only perform project-level FWD testing. Utah We measure surface temperature. Wisconsin No testing is done on network level.

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91 Question 37: Research level FIGURE B33 Survey responses to Question 37, Research: "For each of the following levels, describe your flexible pavement measurement variables, where applicable."

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92 TABLE B9 Survey question 37: "For each of the following levels, describe your flexible pavement measurement variables, where applicable." Flexible pavement temperature gradient holes for research Responding No. of Temperature Temperature Gradient Temperature Gradient Hole State Gradient Holes Hole Depth(s) Measurement Frequency Florida 3 2 in. -- Idaho 1 3 in. 20 min Illinois 1 5 in. -- Louisiana 1 1 in. 1 min Montana 1 1 in. 1 min Vermont 2 Mid-depth 120 min Note: -- = no response given. TABLE B10 Survey question 37: "For each of the following levels, describe your flexible pavement measurement variables, where applicable." Other flexible pavement testing variables for research Responding State Other Testing Variables California Recorded data for temperature is ambient and pavement surface. Colorado We do what is requested by the customer. No set procedure for research. Idaho If the test section is short, test (temperature gradient) hole at the beginning and end of testing but not less than once per hour. Iowa Everything varies by project. Kansas Varies (by project). Maryland Extremely variable dependent on requirements. Nevada We use infrared surface temperatures for gathering temperature data. This measurement is taken at every test location. New York Load transfer efficiency tests are performed on PCC joints. North Carolina Asphalt surface temperature is measured at every drop location. Texas Many variables. Utah Same testing procedure (as project level) unless something specific is asked for. Virginia Drop sequence and sensor spacing is as requested. Question 38: Other levels TABLE B11 Survey question 38: "For each of the following levels, describe your flexible pavement measurement variables, where applicable" (other levels used) Temperature Responding State Description Loading Conditions Sensor Spacings Gradient Holes Other Testing Variables 4 replicate drops at 0, 8, 12, 24, 36, Surface and air tempera- Alaska Airport--B747 None 55 kips each 48, 60, and 72 in. tures are measured 0, 8, 12, 18, 24, Spring load 3 replicate drops at North Dakota 30, 36, 48, and None -- restrictions 7, 9, and 9 kips 60 in. 2 replicate drops at 4 Infrared (temperature Washington Load transfer -12, 0, and 12 in. None lb each measurement) Note: -- = no response given.