1. Mobilization and Site Preparation • Mobilize equipment, labor, and materials to the project site. • Notify DPW and Detroit Water and Sewerage Department (DWSD) prior to start of work. • Post “No Parking” and “Work in Progress” signs in accordance with City of Detroit ordinances. • Implement traffic control and pedestrian safety measures per MDOT Work Zone Safety Guidelines. 2. Demolition and Concrete Removal • Saw-cut and remove existing deteriorated concrete pavement in the alley from the sidewalk to the first undisturbed slab in the alley. Revised 8/28/2024 • Properly dispose of debris at a licensed disposal/recycling facility per Detroit environmental regulations. • Protect existing utilities, fencing, and structures during demolition. 3. Subgrade and Base Preparation • Excavate and regrade subgrade to allow for proper drainage and concrete thickness. • Compact subgrade to a minimum of 95% Standard Proctor Density; submit compaction test reports if requested. • Install 21AA crushed limestone base material (per DPW Standard Specifications) to a depth of 6", compacted in lifts. • Verify grade and slope to ensure positive drainage toward storm inlet. 4. Storm Drain Adjustment • Remove existing storm drain grate, frame, and adjust casting height to match final concrete surface elevation. • Adjustments to be made using approved riser rings or brick/mortar per DWSD specifications. • Verify alignment with existing drainage pipes and ensure inlet is not blocked. • Frame and cover must be City of Detroit-approved (typically Neenah R-3705 or equivalent). • Reset and seal all storm structure joints with non-shrink grout or approved sealant. • Test system for proper flow before concrete pour. 5. Concrete Installation • Install #4 rebar (or wire mesh) as required, at 18" O.C.E.W. minimum. • Pour 6" thick concrete pavement using MDOT Grade P1 concrete (minimum 4,000 PSI compressive strength). • Place expansion joints at all cold joints and contraction joints at 10' intervals, or as directed. • Finish with a light broom texture and edge all joints. • Cure concrete using approved curing compound per City of Detroit DPW guidelines.
