450 Page 309450 PIPE CULVERTS
450.1DESCRIPTION
This work consists of furnishing and installing polyethylene pipe, concrete and metal pipe, storm drains, and cattle passes excluding structural plate pipe and structural plate pipe arch culverts.
450.2MATERIALS
Materials will conform to the following Sections: A.Reinforced Concrete Pipe (RCP): Section 990. B.Corrugated Metal Pipe: Section 990. C.Corrugated Polyethylene Pipe: Section 990. D.High Density Polyethylene Pipe: Section 990. E.Flexible Watertight Gaskets: Section 990. F.Drainage Fabric: Section 831, Type A.
450.3CONSTRUCTION REQUIREMENTS
A.Reinforced Concrete Pipe (RCP) Culvert: All RCP sections, except pipe located between drop inlets, manholes, and junction boxes, will be tied with tie bolts as shown in the plans. All RCP sections only entering or exiting drop inlets, manholes, and junction boxes will be tied with tie bolts. The maximum allowable gap at any point between two sections of RCP will be 1 inch. The tie bolts will only be used to hold the completed RCP sections together and will not be used for pulling the RCP sections together. Lift holes will be covered or plugged to the satisfaction of the Engineer to prevent backfill from entering the pipe. When flexible watertight gaskets are used, the Contractor will install the flexible watertight gaskets in accordance with the manufacturer’s instructions. Unless otherwise specified in the plans, the RCP may be either tongue and groove or bell and spigot style RCP meeting the following requirements for each type of RCP allowed. 1.Tongue and Groove Style RCP: Tongue and groove style RCP culverts will be laid with the groove end of the pipe upstream and inserting the tongue end into the groove. Except where flexible watertight gaskets are specified, each joint will be effectively protected against infiltration of backfill soil by using a flexible watertight gasket conforming to Section 990, by filling the joint space with a sealant conforming to ASTM C990, or by providing a circumferential wrap on the exposed portion of the pipe joint above the cradle with a 1 foot wide strip of drainage fabric around the perimeter of the pipe. The drainage fabric will be centered over the joint. If the Contractors method of installation doesn’t secure the drainage fabric over the center of the joint while placing backfill, the Contractor 450 Page 310is required to use construction adhesives. A combination of sealer and drainage fabric materials will be allowed. 2.Bell and Spigot Style RCP: Bell and spigot style RCP culverts will be laid with the bell end of the pipe upstream and fully inserting the spigot end into the bell end. A flexible watertight gasket is required for this connection. B.Corrugated Metal Pipe Culverts: Corrugated metal pipe culverts will be laid with outside laps of circumferential joints pointing upstream and with the longitudinal laps on the sides. The ends of the pipe sections will be approximately 1 inch apart to enable corrugations of the bands to mesh with the corrugations of the pipe. C.Polyethylene Pipe Culverts: Corrugated polyethylene pipe culverts and high density polyethylene pipe culverts will be installed according to manufacturer recommendations. D.General: Multiple lines of pipe culverts will be accurately laid in parallel lines in all planes. The amount of camber will depend on the height of fill and nature of the supporting soil. Equipment capable of gently lowering the sections of pipe into place will be provided. Dropping the pipe into place will not be permitted. E.Excavation: Trenches will be excavated to a width that allows for proper jointing of the pipe and compaction of the bedding and backfill material under and around the pipe. Where feasible, trench walls will be vertical. The trench bottom will be compacted in accordance with Section 421.3 C for its full length and width. A flat bed will be provided for cattle passes. The foundation for each type of bedding will provide a uniform stable support. Removal of unstable material or rock below bedding grade will be performed as set forth in Section 421. F.Bedding: The pipe bedding will conform to one of the specified classes described below. When no bedding class is specified, the requirement for Class C bedding will apply. 1.Class A Bedding: This bedding will consist of a continuous concrete cradle conforming to the plan details. 2.Class B Bedding (Ring Compression Design): Material will be excavated to a depth of 12 inches below the external bottom of the pipe and to a width equal to the external diameter of the pipe plus 1 foot. The excavated area will be backfilled with select fill material to form a bed that is at least 15% of the pipe height above the external bottom of the pipe. The material will be thoroughly compacted to provide a firm uniform foundation. The foundation will then be shaped
granular material conforming to Section 421.2 B. The Contractor will ensure the cradle is constructed at an elevation such that after placing the 3 inches of granular material in the cradle, the flowline elevation of the pipe is correct. Select fill material will then be placed in 6 inch layers and compacted with mechanical tampers, to at least 30% of the overall pipe height. Select fill material will 450 Page 311consist of stable material free of organic matter and large rock. If granular material is used, the granular material will meet the requirements of Section 421.2 B. When the external bottom of the pipe is entirely in new embankment constructed with select fill material, the 12 inch undercut will be waived. 3.Class C Bedding: This bedding will consist of an earth or granular cradle of uniform density shaped to fit the lower part of the pipe for at least 10% of its overall height. If granular material is used, the granular material will meet the requirements of Section 421.2 B. G.Backfill above Bedding Grade: Material used for backfill will be embankment material encountered on the project free of organic material and rock or will be as specified in the plans. Moisture and density requirements for backfill will meet the requirements of Section 120 or as specified in the plans. The backfill material will be pre-moistened if necessary to obtain uniform moisture. Selected embankment material will be placed along the pipe in layers not exceeding 6 inches in loose depth and thoroughly compacted by mechanical compactors to the specified density before successive layers are placed. The width of the berms on each side of the pipe will be twice as wide as the external diameter of the pipe or 12 feet, whichever is less. This method of backfilling will be continued until the embankment is at least 2 feet over the top of the pipe. In trench installations, the backfill width will be equal to trench width. The backfill will be brought up evenly on both sides of the pipe for its full length. This method of backfilling will be continued until the embankment is at least 2 feet over the top of the pipe. H.Replacing Disturbed Surfacing Material: If the pipe culvert installation requires the removal or disturbing of surfacing material and no items or quantities for replacement surfacing are provided, disturbed surfacing will be satisfactorily replaced at no additional cost to the State.
450.4METHOD OF MEASUREMENT
A.Furnishing and Installing Pipe Culverts: Furnishing and installing pipe culverts will be measured by the foot of the respective types, classes, and sizes. The length will be obtained by multiplying the nominal length of the sections by the number of sections used. When an installation requires that a section of pipe be cut, such as storm sewer installations, the length will be the actual length required, rounded up to the nearest even 2 feet. B.Furnishing and Installing End Sections: Furnishing and installing end sections for the respective type and sizes of pipe culverts will be measured by the number of complete end sections furnished and installed. C.Replacing Disturbed Surfacing Material: Measurement will not be made for this item. 450 Page 312450.5 BASIS OF PAYMENT A.Furnishing Pipe Culverts: Furnishing pipe culverts will be paid for at the contract unit price per foot for the types, classes, and sizes furnished and accepted. The Contractor may substitute a higher class of pipe than specified at their own expense. Payment will be full compensation for furnishing the pipe, special sections, gaskets, connecting devices, and coupling bands and for elongation, when specified. B.Furnishing End Sections: Furnishing end sections will be paid for at the contract unit price per each for the type and size furnished and accepted. C.Installing Pipe Culverts: Installing pipe culverts will be paid for at the contract unit price per foot for the types, classes, and sizes accepted. Payment will be full compensation for installing the pipe culverts, special sections, gaskets, drainage fabric, construction adhesive, preformed mastic, connecting devices, and coupling bands. Payment will also be full compensation for necessary bedding operations, cost of selecting and placing backfill, furnishing and installing required granular or other bedding materials, necessary excavation, and labor, equipment and all incidentals required. Authorized excavation of material below the external bottom of the pipe will be paid for as specified in Section 421.5 . D.Installing End Sections: Installing end sections will be paid for at the contract unit price per each for the type and size accepted. E.Replacing Disturbed Surfacing Material: Separate payment will not be made. The cost of replacement will be incidental to the pipe installed. 460 Page 313460 STRUCTURAL CONCRETE
460.1DESCRIPTION
This work consists of falsework and form construction, and the furnishing, handling, placing, curing, and finishing of concrete for bridges, box culverts, and miscellaneous structures.
460.2MATERIALS
Materials will conform to the following Sections: A.Cement: Section 750. Type II cement will be used, unless otherwise specified. B.Fine Aggregate: Section 800. C.Coarse Aggregate: Section 820. D.Water: Section 790. E.Admixtures: Section 751 and Section 752. F.Reinforcing Steel: Section 1010 . G.Curing Materials: Section 821. H.Preformed Expansion Joint Filler: Section 860. I.Joint Sealer: Section 870. J.Fly Ash: Section 605 and Section 753. K.Grout: Grout will be a commercially available non-metallic, non-shrink grout capable of attaining a minimum compressive strength of 4500 psi and will conform to the requirements of ASTM C1107.
460.3CONSTRUCTION REQUIREMENTS
A.Concrete Quality and Proportion: The Contractor will design and be responsible for the performance of all concrete mixes used in structures. Mix designs will be modified during the course of the work when necessary to assure compliance with the requirements for strength and consistency. All mix designs and any modification thereto, including changes in admixtures, will be approved by the Concrete Engineer prior to use. Mix design data and test results will be recorded on a DOT-24 and submitted to the Engineer a minimum of 40 calendar days prior to anticipated use. The mix design will produce a concrete conforming to the following requirements: