bridge deck overlay,
pavement with reduced thickness, and
Also, because hooked-end steel fibers are the industry standard for fiber reinforced concrete, Dr. Ramakrishnan proposed to collect data from a hooked-end steel fiber reinforced concrete (SFRC) pavement test section. This was very convenient because the City of Rapid City already had plans to construct an SFRC test section on the same route. From these test sections, Dr. Ramakrishnan collected and evaluated a significant amount of data. The data shows hardened concrete properties of NMFRC are greatly improved as compared to plain concrete and are the same or slightly better than hook-end steel fiber reinforced concrete. Additional inspections have been completed, since the time of the interim report, which indicate that the test sections continue to perform well. It was observed that none of the test sections have experienced any additional cracking since the interim report and cracks that occurred prior to that time are not widening due to the fibers.
The economics of the fiber concrete test sections were difficult to evaluate for this study because:
NMFRC is a non-standard material,
test sections were small,
contractors protected themselves by raising their bid,
life expectancy of each NMFRC test section is unknown,
type, frequency, and cost of maintenance is unknown, and
short study duration.
Therefore, qualified cost assumptions were made in the final report for the NMFRC whitetopping, Jersey Barrier, and deck overlay. Minimal or no cost analysis is given for the full depth pavement because too many assumptions would have to be made to give reasonable costs. A better cost analysis for an NMFRC full depth pavement will be conducted from a subsequent study which came as a result of the interim recommendations of this study.
The panel believes the study produced good results and feels that the use of NMFRC in some applications can assist the Departments effort to improve South Dakotas highway network.