Specifications - City of Montpelier, Vermont

Montpelier District HeatingCity of Montpelier, VTIssue Date:September 28, 2012Title:02550 – CurbingPage #:12 of 13B. MIXING AND PLACING: Compaction of concrete placed in the forms shall be byspading or other approved methods. Forms shall be left in place for 24 hours or until theconcrete has set sufficiently so that they can be removed without injury to the curbing.Upon removal of the forms, the exposed curbing face shall be dressed finished.C. SECTIONS: Curbing shall be constructed in sections having a uniform length of 10 feet(3 m), unless otherwise specified. Sections shall be separated by open joints 1/8 inch (3mm) wide except at expansion joints.D. EXPANSION JOINTS : Expansion joints shall be formed at the intervals shown on thePlans using a preformed expansion joint filler having a thickness of 1/4 inch (6 mm).They shall be constructed at 20 feet (6 m) intervals or as directed by the Engineer. Whenthe curb is constructed adjacent to or on concrete pavement, expansion joints shall belocated opposite or at expansion joints in the pavement.E. CURING:1. General: Protect freshly placed concrete from premature drying and excessivecold or hot temperatures.2. Evaporation Control: In hot, dry, and windy weather, protect concrete from rapidmoisture loss before and during finishing operations with an evaporationcontrolmaterial. Apply according to manufacturer's instructions after screeding and bullfloating, but before floating.3. Begin curing after finishing concrete but not before free water has disappearedfrom concrete surface.4. Curing Methods: Cure concrete by moisture curing, moistureretainingcovercuring, curing compound, or a combination of these as follows:a. Moisture Curing: Keep surfaces continuously moist for not less than 7 dayswith the following materials:i. Water.ii. Continuous waterfog spray.iii. Absorptive cover, water saturated, and kept continuously wet. Coverconcrete surfaces and edges with a 12inch lap over adjacent absorptivecovers.b. MoistureRetainingCover Curing: Cover concrete surfaces with moistureretaining cover for curing concrete, placed in widest practicable width, withsides and ends lapped at least 12 inches, and sealed by waterproof tape oradhesive. Immediately repair any holes or tears during curing period usingcover material and waterproof tape.5. Curing Compound: Apply uniformly in continuous operation by power spray orroller according to manufacturer's directions. Recoat areas subjected to heavyrainfall within 3 hours after initial application. Maintain continuity of coating andrepair damage during curing period.F. BACKFILLING : After the concrete has set sufficiently, the spaces in front andback of the curb shall be filled to the required elevation with layers of not more than 6inches (150 mm) of the same material as the bedding and thoroughly tamped.CURBING 02550 12