GJN4579 Pavement Srvcs Contract #2009-00237

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Matt Rodrigues December I1, 2008 Page 3 • weekly bus volumes for each route on the project segments • updated as built information for the segments • base maps of the street segments with the basis for the project stationing Proposed Work Scope Project Reconnaissance The project engineer will inspect the streets to become familiar with the pavement conditions, identify the probable type of rehabilitation work and to refine the field testing program. Non-destructive Deflection Testing Non-destructive deflection testing will be conducted using our KUAB Falling Weight Deflectometer (FWD), which complies with ASTM D4694 and is annually reference calibrated at the FHWA Western Regional FWD calibration center (current reference calibration conducted 10/10/2008). The testing will be accomplished in accordance with ASTM D4695 Level 2 and will be conducted at 100-ft intervals in the outer wheel paths of the through travel lanes. The FWD testing will be conducted during the normal workweek between the hours of 9 AM and 4 PM. We estimate that the FWD testing will take approximately 3 days to complete and we will provide traffic control consisting of signing and flaggers to direct traffic around our operation. The FWD deflection data will be analyzed using our PAYBACK softwate to calculate the effective structural number of the existing pavement structure (SNeff) and the resilient modulus (Mr) of the subgrade soil at each FWD test location. The SNeff values will be analyzed to delineate groups of test points (analysis units) having statistically similar values and to select locations for pavement core explorations at FWD test point(s), with backcalculated SNeff value(s) that are representative of the. SNeff values within the analysis. units. Pavement Core Explorations Full depth core explorations (supplemented with borings to a maximum depth of 3 ft below subgrade level) will be accomplished at up to 30 locations at an average frequency of one location per approximately 1,260 lane-ft (through lanes only). The explorations will be performed at representative FWD test locations selected from review of the backcalculated SNeR values. In addition, surface core explorations (through the bound layer(s) only) will be conducted at up to 8 locations on Coburg Rd to investigate the depth and mode of cracking. The core samples from all explorations will be inspected for evidence of asphalt stripping damage, top-down cracking and delamnnation between lifts. We will log and classify the existing pavement layers and subgrade sail at each of the full depth core explorations and will log the bound layer(s) at each of the surface core explorations. The core exploration locations and core samples will be photographed for documentation of pavement condition and the condition of the bound materials. The explorations will be conducted during the normal workweek between the hours of 9 AM and 4 PM. We estimate that the core explorations will take 5 days to complete and we will provide traffic control consisting of signing and flaggers to direct traffic around our work areas. We will patch the core holes using "Instant Road Repair", a polymerized cold patch material, compacted by vibratory hammer. subgrade Soil Investigation & Testing Jar samples of subgrade soil will be obtained at full depth core explorations for laboratory testing to determine in situ water content and for examination to refine the field soil classification. Additionally, penetration tests will be conducted at full depth core explorations in the segments where reconstruction . may be necessary to check for the possible presence of weak layers within the upper 2 ft of the subgrade. The penetration tests will be conducted in accordance with ASTM D6951 by portable