Utilization of Traffic Speed Deflectometer for Pavement Management

US Transportation Collection2021PDFTech ReportHuynh, NathanGassman, SarahMullen, RobertPierce, Charles E.Chen, YucheAhmed, NazmusUniversity of South Carolina. Dept. of Civil & Environmental EngineeringUnited States. Federal Highway Administration. South Carolina DivisionSouth Carolina. Dept. of Transportation. Office of Materials and ResearchSouth Carolina. Dept. of Transportation. Office of Materials and ResearchUnited StatesSouth CarolinaDeflection testsPavement distressPavement maintenanceSpeedTrafficFHWA-SC-21-04SPR No. 748Draft Final ReportThis project investigated how the Traffic Speed Deflectometer (TSD) data the South Carolina Department of Transportation (SCDOT) obtained as part of the pooled fund studies (i.e., TPF-5(282) and 5(385)) can be used to improve the selection of candidate projects for rehabilitation. The analysis using approximately 950 miles of TSD data collected on eight SC primary routes indicated that there is a low correlation between Structural Condition Index (SCI) and Pavement Quality Index (PQI). This finding confirmed prior knowledge that PQI does not accurately portray the pavement\u2019s underlying conditions related to remaining service life or the potential for future deterioration. The SCI12 performance indicator was selected to quantify the structural condition of a pavement, where good pavements are those with SCI12 values below 1.6, fair are those with SCI12 values between 1.6 and 3.3, and poor are those with SCI12 values above 3.3. A TSD score was developed using the percentages of poor pavements to assist the SCDOT with candidate project selection. This TSD score can be easily incorporated into the current workflow of project selection with the implemented Excel-based tool.113