City of Riverside, Citywide Pavement Coring for Street Maintenance Improvements FY21-22

Twining provided Geotechnical Engineering Services for the City of Riverside’s Citywide Pavement Coring Street Maintenance Improvements for Fiscal Year 2021/22. Our scope of work included:

• Mark coring locations; obtain utility clearance and construction related permits, such as the street opening permit from the City; adhere to all City requirements as indicated with in the RFP.
• Provide traffic control during all activities in accordance with the Work Area Control Manual Handbook
• Characterize and identify the thickness of all existing pavement materials to the subgrade at sampling locations; perform visual inspection of each borehole for evidence of any wet utilities leakage and document accordingly; perform coring per the City’s attached exhibits of the RFP
• Collect subgrade soil samples at each sample location, to a depth interval of 30 inches (with 30 to 60 inches for cores 123-128) for identifying soil classification, moisture content and R-value analysis; test R-values and determine the boring location identified per the attached exhibits; identify the presence of any interlayer/geotextile material
• Provide a spreadsheet summarizing the core sampling results, including core number, location, R-values (if applicable), moisture content percentage, asphalt concrete thickness, base thickness (if applicable), site condition, soil classification, and any field observation notes