Falling Weight Deflectometer Usage (2008)

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24 ing. Conversely, 30% gave training intervals of from 4 to 6 months. On elaboration, 33% of SHAs explicitly stated that training is provided on the job. Additionally, three states— Nevada, North Carolina, and South Carolina—require new operators to demonstrate proficiency, either by successfully completing data-gathering operations under supervision or by passing a test (Appendix B, questions 64–68). SHA operator training may be complemented or sub- stituted with vendor-provided training. The purchase of an FWD from any of the four manufacturers includes a training session. Durations and content of training sessions are sum- marized in Table 5. Although some localities have unique needs, certain skill sets are universally desirable for FWD operators. According to Martin (2006), these skill sets are as follows: • Equipment setup and operation familiarity, For FWD data to be useful to pavement designers, it must be collected properly. Without proper training between FWD operators, data analysts, and pavement designers, miscom- munications may result. Furthermore, training prevents minor mechanical difficulties from becoming major opera- tional obstacles. In this chapter, training of FWD operators and data analysts is discussed. quaLiFicaTions Falling Weight deflectometer operators qualifications When asked about their FWD operator training practices, 66% of SHAs responded that they provide training to new FWD operators. When asked about training duration, 37% of survey respondents stated that before a newly hired FWD operator is on the job, one month or less is devoted to train- CHAPTER SIX personneL TraininG TABLE 5 FWD VENDOR-PROVIDED OPERATOR TRAINING SUMMARy FWD Vendor Training Duration Concepts Covered Certificate Available? Carl Bro 5 days Included with purchase of new FWD equipment yes Introduction to equipment, including setup and shutdown Data collection software use Basic maintenance and troubleshooting Dynatest — Included with purchase of new FWD equipment Refresher courses available for newly hired operators — Tow vehicle tour Introduction to equipment, including setup and shutdown User manual overview Data collection software use Basic maintenance and troubleshooting Support contact information — JILS 7 days — — KUAB 3 days Included with purchase of new FWD equipment Ongoing telephone support is provided — Introduction to equipment, including setup and shutdown Equipment operation, including testing patterns Data collection software use Basic maintenance and troubleshooting Equipment calibration Note: — = no response given.

25 calibration center operator qualifications Training requirements differ slightly from one calibration center to another. For example, Pennsylvania calibration center technicians are trained by Cornell University and are certified by MACTEC. The calibration center in Minne- sota, on the other hand, has not yet implemented an in-house training program, but it plans to do so in the future. TraininG cerTiFicaTions Certificate programs for FWD operators and data analysts are rare. One state—South Carolina—and one FWD vendor— Carl Bro—stated explicitly that a certification program is in place for FWD operators (Appendix B, questions 70). The South Carolina certificate is earned when a new operator rides “with a certified operator for a period of time to show proficiency, and pass a test” (Appendix B, questions 71). addiTionaL TraininG opporTuniTies Falling Weight deflectometer user’s Group Sixty-one percent of SHAs surveyed send representatives to the annual FWDUG meeting (Appendix B, questions 72). The FWDUG was started in 1992 as a forum to “share information and experiences in the practical aspects of FWD • Basic familiarity with signal processing, • Automotive maintenance, and • Computer skills. In addition to those skills, FWD operators should be able to clearly communicate with the office and take direction. Furthermore, FWD operators should be exposed to data pro- cessing and analysis techniques. With these skills, operators can spot erroneous data before the errors have a chance to propagate, thus saving agencies time and money. Falling Weight deflectometer data analysts qualifications Sixty-six percent of SHAs reported that they provide training to new FWD data analysts. Training duration mostly fell into one of two responses; 31% stated 1 month or less of training was provided, and 27% stated that training was provided for 6 months. When asked for more details, six SHAs explicitly stated that training is provided on the job. Additionally, two states—Nevada and North Carolina—require new analysts to demonstrate proficiency, either by successfully completing data-gathering operations under supervision or by passing a test (Appendix B, questions 66, 68–69). Three SHAs stated that vendors provided at least some training. New FWD equipment purchases include training sessions. Details of these training sessions are described in Table 6. TABLE 6 FWD VENDOR-PROVIDED DATA ANALyST TRAINING SUMMARy FWD Vendor Training Duration Concepts Covered Carl Bro 5 days Introduction to road design software, including data import, quality check, and calculation Basic pavement design theory Presentation of calculation results Basic troubleshooting Dynatest — Included with purchase of new FWD equipment Refresher courses available for newly hired operators Smoothing User manual overview Support contact information JILS — — KUAB — Development of a FWD test pattern Data acquisition and data reduction Pavement section definition Load and temperature normalization of data Back-calculation of layer moduli values Load transfer and void detection in PCC pavements Structural evaluation of existing pavements Determining remaining structural life and overlay thickness design Note: — = no response given.

26 national highway institute A division of FHWA, the National Highway Institute (NHI), is a clearinghouse for highway construction and mainte- nance education materials. NHI currently does not offer a training course for FWD usage, but 85% of SHAs surveyed would support one. A course previously offered by NHI dis- cussed pavement deflection analysis, including FWD usage (Pavement Deflection Analysis 1994). testing and data analysis.” Meetings are held once per year in various cities across the United States. Free exchange of ideas is encouraged. Currently, Patricia Polish of the Nevada DOT serves as the FWDUG’s executive secretary. Meetings are typically held in October or November (FWD: Introduc- tion 2007).