Markings
Article 1 — Description
Furnish mobile retroreflectivity data collection (MRDC) for pavement markings on roadways as shown o n the plans or as designated by the Engineer. Conduct MRDC on dry pavement only. Provider is defined as the Contractor or s ubcontractor that collects the MRDC data.
Article 2 — Equipment and Personnel
2.1 Mobile Retroreflectometer . Provide a self-propelled, mobile retroreflectometer certified by the Texas A&M
Transportation Institute (TTI) Mobile Retroreflectometer Certification Program .
2.2 Portable Retroreflectometer . Provide a portable retroreflectometer that uses 30-meter geometry meeting
the requirements described in ASTM E1710. Maintain, service, and calibrate all portable retroreflectometers in conformance with the manufacturer’s instructions.
2.3 Operating Personnel for Retroreflectometer . Provide all personnel required to operate the mobile
retroreflectometer and portable retroreflectometer. Ensure MRDC system operator has a current certification from the TTI Mobile Retroreflectometer Certification Program to conduct MRDC using the certified mobile retroreflectometer.
2.4 Additional Personnel . Provide any other personnel necessary to compile, evaluate, and submit the data
obtained from MRDC.
2.5 Safety Equipment . Supply and operate all required safety equipment to perform this service.
Article 3 — Mrdc Documentation and Testing
Document all MRDC by county and roadway or as directed by the Engineer. Submit all data to the Department and to the TTI Mobile Retroreflectometer Certification Program no later than 3 working days after the day the data are collected. Submit all raw unmodified data collected in addition to all other data. Provide data files in Microsoft Excel or another approved format. Provide measurement notification and field tests as specified. Verification and referee testing may be conducted at the Department’s discretion.
3.1 Preli minary Documentation Sample . Submit a sample data file, video, and map of MRDC data in the
required format at least 10 working days before beginning any work. The format must meet specification and be approved before any work may begin.
3.2 Initial Documentation Review and Approval . The Department will review documentation submitted for the
first day of MRDC, and if it does not meet specification requirements, will not allow further MRDC until deficiencies are corrected. The Department will inform the Provider no later than 3 working days after submittal if the first day of MRDC does not meet specification requirements. Time charges will continue unless otherwise directed by the Engineer. 912 3.3. Data Files. In addition to the raw unmodified data as output from the mobile retroreflectometer, provide data files with the following information : date; District name or number ; county name; project control -section -job (CSJ) number; name of mobile retroreflectometer operator; route number with reference markers or other reference information provided by the Engineer to specify the location of beginning and end points for data collection on that roadway ; cardinal direction ; line type (e.g., single solid, single broken, or double solid); line color ; file name corresponding to video; data for each centerline listed separately; average reading taken for each 0.1- mi. interval ( or interv al specified by the Engineer ); accurate Global Positioning System (GPS) coordinates (within 20 ft.) for each interval; color -coding for each interval specifying passing or failing, unless otherwise directed by the Engineer (passing and failing thresholds provided by the Engineer); graphical representation of the MRDC (y -axis showing retroreflectivity and x -axis showing intervals) corresponding with each data file; distance in miles driven while measuring the retroreflectivity of pavement markings ; event c odes (pre- approved) specifying problems with measurement; portable retroreflectometer field check average reading and corresponding mobile average reading for that interval when applicable; and upper validation threshold (may be included separately with the raw data but must be clearly identified with the data collected using that threshold).
3.4 Map. Provide a map in an approved electronic format with each MRDC submission that includes the
following information: date; District name and number ; county name; color -coded 1- mi. intervals (or interval length specified by the Engineer) for passing and failing retroreflectivity values, or retroreflectivity threshold values provided by the Engineer; and percentage of passing and failing intervals , if required by the Engineer.
3.5 Video . Provide a high- quality DVD or electronic video file with the following information:
date and corresponding data file name on the label; District name or number ; county name; route number with reference markers or other specified reference information to indicate the location of beginning and end points for data collection on that roadway ; and retroreflectivity values presented on the same screen with the following information: • date; • location; • starting and e nding mileage; • total miles; and • upper validation thresholds (may be included separately with the raw data but must be clearly identified with the data collected using that threshold). 913 3.6. Field Comparison Checks Using a Portable Retroreflectometer . At the beginning of each set of mobile measurement, collect at least one portable measurement to assess the accuracy of the calibrated MRDC. If requested by the Engineer, take a set of field comparison readings using a portable retroreflectometer to validate the data collected by MRDC. The Engineer will select the location and the markings to be evaluated. The number of readings should be at least 16 for each marking over the designated measurement interval. List the average portable retroreflectometer reading next to the mobile average reading for that interval wit h the reported MRDC data. Request approval to take field comparison readings on a separate roadway when measuring a roadway where portable retroreflectometer readings are difficult to take. Take the off -location field comparison readings at no additional cost. No more than one request will be made for each project unless the average of the portable measurements exceeds ±15% range of MRDC data. Submit the printout and exported portable retroreflectometer data for all the readings taken for the field comparis on check with the corresponding MRDC data submitted. The mobile average reading must be within ±15% of the portable average reading. The Engineer may require new MRDC for some or all of the pavement markings measured during the time interval before a field comparison check not meeting the ±15% range. Provide the new MRDC at no extra cost to the Department. The Engineer may take readings using a Department portable retroreflectometer to ensure accuracy at any time. The Department’s Materials and Tests Division (MTD) will take comparison readings and serve as the referee if there is a significant difference between the Engineer’s portable readings and the Provider’ s mobile and handheld readings. For best results, take field comparison readings on a relatively flat and straight roadway when possible.
3.7 Periodic Field Checks at Pre- Measured Locations . When requested by the Engineer, measure using the
mobile unit and report to the Engineer immediately after measurement the average retroreflectivity values for a specified pre- measured test location. The Engineer will have taken measurements at the test location within 10 days of the test. The test location will not include pavement markings less than 30 days old. If the measured averages do not fall within ± 15% of the pre- measured averages, further calibration and comparison measurements may be required before any further MRD C. Submit the MRDC results for the test location to be compared to the Engineer ’s field check measurements.
3.8 Measurement Notification . Provi de notification by email to Mobileretro@tamu.edu
with a carbon copy to the Engineer at least 24 hr . before MRDC to allow for scheduling mobile verification testing.
3.9 Verification T esting . The Engineer or a third party may perform retroreflectivity verification testing within
7 days of the Provider’s retroreflectivity readings. The Provider- submitted retroreflectivity data will be compared to the verification test data to determine acceptability of the Provider ’s mobile retroreflectometer data. Comparison of the data will result in one of the following two scenarios . Provider’s Data Validated . If the difference between Provider ’s and Engineer -third party data is 20% or less, then the Provider’s data is validated. The Provider ’s data will be used for acceptance. Provider’s Data N ot Validated . If the difference between Provider ’s and Engineer -third party data is more than 20%, then the Provider ’s data is not validated. The Engineer -third party data will be used for acceptance and the Provider will be required to take corrective action before additional Provider data collection and may require re- certification of the mobile retroreflectometer and MRDC system operator. If the Engineer determines that the Provider ’s data might be correct, then referee t esting may be requested by the Engineer .
3.10 Referee Testing . MTD will perform referee testing using portable retroreflectometers to determine whether
the markings need to be restriped to meet the required retroreflectivity level. The referee test results will be final. Referee testing will be conducted on the verification test sections using the method for portable retroreflectometers in accordance with Item 666, “Retroreflectorized Pavement Markings.” 914 4. FINAL REPORT Submit a final report in the format specified by the Engineer to the Department’s Traffic Engineering representative within 1 calendar week after the service is complete. The final report must contain a list of all problems encountered (pre- approved event codes) and the locations where problems occurred during MRDC .
Article 5 — Measurement
When MRDC for pavement markings is shown on the plans to be a pay item, measurement will be by the lane mile driven while measuring the retroreflectivity of pavement markings.
Article 6 — Payment
Unless otherwise shown on the plans, the work performed, materials furnished, equipment, labor, tools, and incidentals will not be paid for directly , but will be subsidiary to bid items of the Contract. When MRDC for pavement markings is shown on the plans to be a pay item , the work performed in accordance with this Item and measured as provided under “Measurement” will be paid for at the unit price bid for “Mobile Retroreflectivity Data Collection.” This price is full compensation for equipment, equipment calibration and prequalification, labor, and tools; submitting the raw data and summaries of readings to the Engineer; and incidentals .