One of the primary challenges that face wide-scale implementation of nondestructive evaluation (NDE) methods to assess the condition of the nation’s infrastructure, specifically bridge decks, is the cost associated with data collection. The high cost of data collection and the direct and indirect costs associated with lane closures result in NDE being very expensive. Reducing these high costs can be accomplished through a reduction in the time it takes to perform data collection. Three primary factors affect the amount of time needed to conduct an NDE survey on a bridge deck; equipment testing speed, sampling frequency, and deck size. Research was conducted to evaluate the current NDE sampling frequency methodology and establish if a larger sampling frequency could be used while still maintaining condition assessment effectiveness. Rutgers’ NDE team currently uses a 2x2 ft grid to establish the condition of bridge decks when conducting NDE surveys. A statistical evaluation of the effectiveness of the 2x2 ft grid was done by comparing it to smaller grid spacing on a randomly selected section of a deck. The results of the study established that a 2x2 ft grid provides an accurate assessment of condition when compared to much denser survey frequencies. An analysis was also carried out to establish if a larger grid spacing would provide similar results to the 2x2 ft spacing, so as to decrease survey times while still maintaining an effective condition assessment. Twelve previously evaluated bridge decks were evaluated using various grid spacings larger than 2x2 ft. The results indicated that using a much larger rectangular grid, like 2x8 or 4x6 ft (transverse x longitudinal spacing) provide adequate data to establish the overall condition of a bridge deck while significantly decreasing survey time. The results also indicate that the effectiveness of the larger grid spacing is affected by the technology implemented. The results of this research will aid in improving the speed of NDE surveys which will lower costs making it a more viable option for department of transportations’.

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