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SECTION 3400 ADJUSTMENT OF EXISTING STRUCTURES TO GRADE Revision 5 – January 2008 Page 1 of 3 PART 1 GENERAL 1.1 SCOPE: A. This Section covers the work necessary for adjusting manholes, sumps, catch basins, inlets, valve boxes, meter boxes, monument boxes, and similar structures to required elevation and/or horizontal alignment, complete. PART 2 PRODUCTS 2.1 GENERAL: A. Materials used in adjustment of structures may be materials salvaged from the existing installation and brought to a condition approved for reuse, or materials conforming to the requirements of like material and work referred to herein. 2.2 AGGREGATE BASE: A. Aggregate shall conform to the requirements of Section 2300. 2.3 PCC: A. PCC shall conform to the requirements of Section 2000. 2.4 HOT MIX ASPHALTIC CONCRETE (HMA): A. HMA concrete shall conform to the requirements of Section 2400. 2.5 TACK COAT: A. Tack coat shall conform to the requirements of Section 4220. 2.6 MANHOLES AND CATCH BASINS: A. Manholes and catch basins shall conform to the following sections; Sanitary Sewer Clean Outs Sec. 6200 Sanitary Sewer Manholes Sec. 6510 Catch Basins Sec. 7100 Storm Sewer Manholes Sec. 7500 2.7 CONCRETE GRADE RINGS: A. Concrete grade rings or doughnuts, shall be of size shown on plans and be of 3,500-psi concrete, minimum. ---PAGE BREAK--- SECTION 3400 ADJUSTMENT OF EXISTING STRUCTURES TO GRADE Revision 5 – January 2008 Page 2 of 3 2.8 MORTAR & GROUT: A. Mortars and grouts used to construct grade adjustments on these structures shall conform to Section 2050 “CEMENTITIOUS PATCHING & GROUTING MATERIALS”. PART 3 EXECUTION 3.1 EXCAVATION: A. Excavation shall be unclassified and include all materials encountered to the depths as shown or as directed. 3.2 SAW CUT: A. Saw cut around structure to be adjusted, before new pavement is placed. Do not jack hammer in lieu of saw cut. Replace pavement to previous density and grade. 3.3 BACKFILL: A. Backfill shall be accomplished to ensure an equal or better foundation then adjacent foundation structure. 3.4 RAISING TOPS OF MASONRY STRUCTURES: A. Remove existing frames, covers, and grates to expose the surface on which new mortar or concrete is to be placed. Chip existing surface to a depth of at least 3/4-inch to firm concrete. This surface shall be cleaned by brushing and water moistened prior to placing new concrete thereon. New concrete shall be cured at least three days, after which the frame shall be seated in fresh mortar and brought to proper grade. 3.5 LOWERING TOPS OF MASONRY STRUCTURES: A. Where the top of an existing masonry structure is to be lowered, the masonry portion of the structure shall be exposed to required depth, cut off or removed to an elevation below that established for the bottom of metal frame or cover which is to be reset on masonry and shall then be built up with mortar, concrete, brick, or concrete blocks, or with metal rings or plates to required elevation and top design. 3.6 ADJUSTING METAL STRUCTURES: A. Metal inlets, valves boxes, meter boxes, monument boxes, and other like structures shall be raised or lowered to grade by resetting the entire structure on firm foundation. In the case of raising the structure to a point where it would not enclose or protect its contents, add metal extensions of like design below the original structure. Contractor may replace the structure with a new structure of adequate design as approved. B. Salvaged structures not reused on the project shall become the property of the Owner. ---PAGE BREAK--- SECTION 3400 ADJUSTMENT OF EXISTING STRUCTURES TO GRADE Revision 5 – January 2008 Page 3 of 3 3.7 FRAMES, GRATES AND COVERS: A. Frames, grates, and covers meeting specifications shall be installed to accommodate grade changes per the plans and/or grade staking and secured in a workman like manner. 3.8 MEASUREMENT AND PAYMENT: A. Payment will be made at the unit price for each type of structure modified as indicated in the Bid Proposal and as tabulated in the field for completed work. PART 4 TESTING 4.1 GENERAL A. Testing of materials supplied shall be at the discretion of the Engineer to ensure compliance. END OF SECTION