Agenda - Council - 06/27/2017 - Laserfiche WebLink

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(4) Hardwood blocking shall not be used. Concrete buttresses shall be poured against firm, undisturbed ground and shall be formed in such a way that the joints will be kept free of concrete and remain accessible for repairs. The concrete mix used in buttress construction shall meet the requirements for Grade B concrete in conformance with MnDOT Specification Section 2461. Buttress dimensions shall be a minimum of twelve inches (12") in thickness, and the minimum area, in square feet shall be as follows. PIPE TEE OR 1/32 BEND SIZE PLUG 1/4 BEND 1/8 BEND 1/16 BEND 6" 2.9 3.1 1.6 0.8 8" 3.7 5.3 2.9 1.4 10" 5.7 8.1 4.4 2.2 12" 8.1 13.4 6.6 3.2 16" 15.1 21.4 11.6 5.9 20" 23.2 30.2 18.1 9.3 24" 33.6 48.5 26.1 13.3 Contractors are instructed to size concrete buttress blocking on fittings and dead ends where the blocking must withstand the pressure of larger main line fittings equipped with reducers, for the larger sized main line thrust and not for smaller fitting size only. This is of particular importance on tees and crosses where the main size is reduced on the run from large to small size by use of reducers. All metal parts of tie rod or strap type restraints shall be galvanized or coated with other approved asphaltic type rustproofing. All necessary fittings, bands, tie rods, nuts, and washers, and all labor and excavation required for installation of reaction restraints shall be incidental to the installation of the pipe, unless a specific payment item is provided in the bid proposal. A5 Polyethylene Encasement of Pipeline Wherever so required by the Plans, Specifications, or Special Provisions the pipeline, including valves, fittings, and appurtenances, shall be fully encased in polyethylene film meeting the requirements of these Specifications. The film shall be furnished in tube form for installation on pipe and all pipe -shaped appurtenances such as bends, reducers, off- sets, etc. Sheet film shall be provided and used for encasing all odd -shaped appurtenances such as valves, tees, crosses, etc. The polyethylene tubing shall be installed on the pipe prior to being lowered into the trench. Tubing length shall be sufficient to provide a minimum overlap at all joints of one foot or more. Overlap may be accomplished with a separate sleeve tube placed over one end of the pipe prior to connecting another section of pipe, or by bunching extra overlap material at the pipe ends in accordion fashion. After completing the pipe jointing and positioning the overlap material, the overlap shall be secured in place with plastic adhesive tape wrapped circumferentially around the pipe not less than three (3) turns. After encasement, the circumferential slack in the tubing film shall be folded over at the top of the pipe to provide a snug fit along the barrel of the pipe. The fold shall be held in place with Page 29