City Council Agenda and Packet 2016 04 01 PAVEMENT TOUR

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What effect does each distress have on the score of a street? To understand what effect a type of distress has on our street system one must understand roughly how the pavement management system calculates the score. Basically, each type of distress is observed for severity and measured for the total quantity in linear feet or square feet for the section of street being surveyed. The totals of the distresses are then converted into a percentage of the entire section for each type and finalized into an average OCI score for that section of street. The following table illustrates the score a section of street 2 lanes wide (24 ft) and 100 feet long (imagine one side of Via Appia) would be for each type of distress previously shown and as may be observed in the field. OCI Score for different types of Distresses on a 2 Lane (24 ft), 100 ft Section of Street Type of Distress Severity of Distress Size of Distress Measurement PCI Score New Overlay - - - 100 Chip Seal - - - 90 - 100 Longitudinal /Transverse Low 400 ft 400 If 79 Patch Low 50 ft x 12 ft 600 sf 75 Block Cracking Low Whole Section 2400 sf 72 Longitudinal /Transverse Medium 400 ft 400 If 64 Block Cracking Medium Whole Section 2400 sf 57 Alligator Cracking Low 50 ft x 12 ft 600 sf 57 Alligator Cracking Medium 50 ft x 12 ft 600 sf 42 What does this mean in regards to Preventative Maintenance? Using our same example section of road the following table shows what score can be achieved when preventative maintenance is performed and the same distresses are transformed to other types of distresses. Please note that these are examples and various ranges to try and provide an idea of what occurs. In general, the entire street network is surveyed to provide an idea of the condition of each street and the average OCI for the entire City. As it becomes time to perform the actual work on each street, staff assesses that street in full detail including localized problems, traffic volume, and other factors that may contribute to street distresses or ongoing issues. The appropriate treatment or work is then selected and performed. Effect of Preventative Maintenance on the OCI Score for a 2 Lane (24 ft), 100 ft Section of Street Existing PCI Preventative Maintenance Improved Distress New PCI Alligator — Low 57 Patching Patch - Low 75 Alligator — Medium 42 Patching Patch — Low 75 Long /Tran — Medium 64 Crack Seal Long /Tran — Low 79 Block — Medium 57 Crack Seal Block — Low 72 Varies 0 -40 Reconstruct New 100 Varies 26 - 56 Overlay New 100 Varies 41- 69 Chip Seal Like New 90 -100