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From page 53... ... 53 Of the 44 state DOTs that responded to the survey, 38 indicated that they use an IRI-based smoothness specification for AC-surfaced pavements, with 26 state DOTs indicating that they use such a specification for both AC- and PCC-surfaced pavements. Procedures followed by the state DOTs that use an IRI-based smoothness specification regarding who collects the inertial profile data, the type of profilers allowed to collect data, certification of profilers, certification of profiler operators, height-sensor types specified for the profiler, data collection procedures, and QA procedures for the data are described in this chapter. Read the entire page →
From page 54... ... 54 Inertial Profiler Certification for Evaluation of International Roughness Index is one where the IRI computed from the data collected by the profiler has satisfied a specified repeatability and an accuracy criterion. The accuracy criterion is based on comparing the IRI from the profiler with the IRI from a reference device. Read the entire page →
From page 55... ... Collection of Inertial Profile for IRI Construction Acceptance 55 a breakdown of the procedures used by these 22 state DOTs regarding certification or approval of the contractor-owned equipment. As shown in Table 10, 16 state DOTs allow contractors to use certified contractor-owned profilers to collect data, while two state DOTs allow contractors to use approved profilers to collect data. Read the entire page →
From page 56... ... 56 Inertial Profiler Certification for Evaluation of International Roughness Index location, except for one. This state DOT has only one profiler that is under the jurisdiction of another division in the DOT. Read the entire page →
From page 57... ... Collection of Inertial Profile for IRI Construction Acceptance 57 Device Used to Collect Reference Data for Certification In 23 of the 25 states with in-state certification programs, SurPRO is used to collect reference data. The reference data in one of the two remaining states are collected using an ARRB Walking Profiler, and in the other state the data are collected using a SSI Walking Profiler. Read the entire page →
From page 58... ... State Number of Sections Surface/Texture Types and IRI Levels Number Used for Certification AC PCC Surfaced Surfaced 1 4 ─ DAC (IRI < 70, 70 to 120, > 120 in./mi) Read the entire page →
From page 59... ... Collection of Inertial Profile for IRI Construction Acceptance 59 Written Procedures for Certification of Profilers Of the 25 states that responded to the survey indicating that they have an in-state certification program, 21 disclosed that they have a written procedure for certifying profilers. A state DOT that currently does not certify profilers because of the lack of a suitable test site also declared that they have a written procedure for certifying profilers. Read the entire page →
From page 60... ... 60 Inertial Profiler Certification for Evaluation of International Roughness Index Approval of Contractor-Owned Profilers Two state DOTs approve contractor-owned profilers for collecting data on the final paved surface for construction acceptance. The procedure for approval includes determining the accuracy of the profiler by comparing the IRI from the profiler with the IRI from the state DOT– owned profiler, which is treated as the reference. Read the entire page →
From page 61... ... Collection of Inertial Profile for IRI Construction Acceptance 61 equipment is collecting consistent data. The following are some of the procedures indicated by the state DOTs for verifying the equipment: • One state DOT indicated that it performs an annual verification of all profilers owned by the state DOT at a test section. Read the entire page →
From page 62... ... 62 Inertial Profiler Certification for Evaluation of International Roughness Index contractor operators are required to be certified, the state DOT operators are also required to be certified. Table 17 shows operator certification requirements in the 22 states where the DOT accepts contractor-collected data on the final paved surface for construction acceptance. Read the entire page →
From page 63... ... Collection of Inertial Profile for IRI Construction Acceptance 63 The various combinations of procedures used in the 22 states that have an in-state profiler operator certification program to certify operators are shown in Table 18. Table 19 shows the number and percentage of state DOTs that require operators to satisfy each of the following criteria (based on the 22 state DOTs -- out of the 44 that responded to the survey -- that require operators to be certified) Read the entire page →
From page 64... ... 64 Inertial Profiler Certification for Evaluation of International Roughness Index certifies DOT operators indicated that they only require a DOT operator to be certified once, and they hold quarterly verifications to ensure operators are following correct operational procedures. This state DOT is omitted from Figure 15. Read the entire page →
From page 65... ... Collection of Inertial Profile for IRI Construction Acceptance 65 Table 21 shows the number of state DOTs adopting each of the documentation practices described previously, as well as the percentage of state DOTs adopting each of the practices. (Note: Percentages are based on eight state DOTs -- out of the 44 state DOTs that responded to the survey -- that require contractor operators to be certified. Read the entire page →
From page 66... ... 66 Inertial Profiler Certification for Evaluation of International Roughness Index • Iowa DOT indicated that profilers certified in another state will be allowed to collect data, but the profiler must run specified test sections to verify the data collected by the profiler before the profiler is approved to collect data. • Ohio DOT indicated that it might allow profilers certified in another state to collect data, but that will be approved on a case-by-case basis and will require a comparison of the data collected by the profiler with data collected by a state DOT–owned profiler. Read the entire page →
From page 67... ... Collection of Inertial Profile for IRI Construction Acceptance 67 Out of the 21 states shown in Table 22, three states do not use an IRI-based smoothness specification for PCC pavements. Of these three states, two do not specify a height-sensor type for the profiler, and the other state specifies an SS laser for all types of AC-surfaced roads. Read the entire page →
From page 68... ... 68 Inertial Profiler Certification for Evaluation of International Roughness Index • One state DOT indicated that it performs IRI verification of the profiler weekly on a site established on an in-service road, while another state DOT indicated that it performs verification monthly on a 0.5-mi-long road. Pre-Operational Checks Performed on Contractor-Owned Profilers When a contractor collects data for construction acceptance, a state DOT representative is expected to check whether the profiler is certified before collecting data (if the state requires a certified profiler to be used) Read the entire page →
From page 69... ... Collection of Inertial Profile for IRI Construction Acceptance 69 The state DOTs that allow contractors to collect data on the final paved surface for construction acceptance were asked to select one of the previous responses or -- if these responses were not appropriate -- to indicate the procedure followed by the state DOT. Table 25 shows the responses provided by the state DOTs. Read the entire page →
From page 70... ... 70 Inertial Profiler Certification for Evaluation of International Roughness Index • One state DOT indicated that referee testing is done by the central office, and the results obtained from the central office profiler is considered to be final. • One state DOT indicated that both inertial profilers are decertified until it can be determined which device is collecting erroneous data. Read the entire page →
From page 71... ... Collection of Inertial Profile for IRI Construction Acceptance 71 2. Educating the contractors about the certification program and getting the contractors to buy into the need for certification. Read the entire page →
From page 72... ... 72 Inertial Profiler Certification for Evaluation of International Roughness Index 10. One state DOT has diamond-ground a new AC surface to evaluate the performance of the profiler on a smooth diamond-ground section. Read the entire page →

From page 53...

... 53 Of the 44 state DOTs that responded to the survey, 38 indicated that they use an IRI-based smoothness specification for AC-surfaced pavements, with 26 state DOTs indicating that they use such a specification for both AC- and PCC-surfaced pavements. Procedures followed by the state DOTs that use an IRI-based smoothness specification regarding who collects the inertial profile data, the type of profilers allowed to collect data, certification of profilers, certification of profiler operators, height-sensor types specified for the profiler, data collection procedures, and QA procedures for the data are described in this chapter.