2501Pipe Culverts

2501.1DESCRIPTION

This Work consists of the construction of pipe Culverts using plant-fabricated pipe and appurtenant Materials or using preformed structural plates fabricated for field assembly, installed primarily for passage of surface water through embankments.

2501.2MATERIALS

A Pipe Provide one of the following types of Culvert pipe meeting the lowest strength class specified in the referenced Specification, unless otherwise shown on the Plans or specified in the Special Provisions. Provide special fabrication or jointing details as shown on the P lans. Provide Culvert pipe with the coating type shown on the Plans or specified in the Special Provisions. B Structural Plate C Aprons Provide aprons of the type required by the Contract. The Contractor may provide and attach galvanized steel aprons to corrugated steel, corrugated polyethylene, polyvinyl chloride, polypropylene , and polymeric coated corrugated steel pipe, unless otherwise specified on the P lans. Do not connect galvanized steel products to aluminum or aluminized steel products. Use GS for smooth galvanized steel aprons and CS for corrugated galvanized steel aprons as shown on Plate 3128.

F Pipe Joint Sealer Materials

2501.3CONSTRUCTION REQUIREMENTS

Install pipe Culverts in accordance with the following requirements: A General Excavate, construct foundations, backfill, and compact Culvert(s) in accordance with the Plans, 2451 “Structure Excavations and Backfills,” and the following: Remove and replace unsuitable foundation Materials encountered at or below the foundation elevation using suitable replacement Materials as directed by the Engineer. Install the replacement Material in Layers 6 inches thick per 2106, “Excavation and Embankment – Compacted Volume Method.” Compact Materials used for bedding and foundation backfill in accordance with the P lans and 2106, “Excavation and Embankment – Compacted Volume Method.” B Entrance Culverts The Contractor may install entrance Culverts without standard bedding unless shown in the Plans or installing plastic pipe. Backfill using Material meeting 1103, “Definitions: Select Grading Material,” and compact per 2106, “Excavation and Embankment – Compacted Volume Method.” C Laying Pipe C.1 General Lay pipe to the line and grade shown in the Plans. Terminate pipes that connect with inlet Structures flush with the inside of the Structure wall. At Culvert connections with an existing inlet Structure, make a suitable connection as approved by the Engineer through the wall of the inlet Structure.

Jack Culverts through the existing earth Structure into position as shown on the Plans or as approved by the Engineer. Ensure the flow line elevation at the starting point for jacking is within 0.1 feet of the staked grade. Do not reverse the flow line grade at any point. Ensure the line and grade at any point within the pipe does not vary by greater than 0.5 feet from the line and grade designated on the Plans. Provide any additional cover required to avoid damage to the pipe during construction. Maintain adequate cover until paving is completed, or until the installation is accepted by the Engineer if paving is not required. Repair or replace pipe damaged by Contractor operations to the satisfaction of the Engineer, at no additional costs to the Department. C.2 Metal Culvert Lay corrugated metal pipes having circumferential joints with the outside laps pointing upgrade and with the longitudinal joints at the springlines. Provide backfill Material in accordance with the Plan, modified to 100 percent passing the 3-inch Sieve within 2 foot of the pipe. Use metal connecting bands, centered over the joint, to join metal pipe sections . Place the pipe sections so that the pipe ends are abutting. Tighten the band to ensure a tight joint so that the soil does not infiltrate into the pipe and the sections do not pull apart. Use approved fasteners, as defined in the applicable Materials Specifications, to assemble structural plate Culverts as required by the manufacturer. Tighten bolts after assembly to a torque of 100 lbf ft to 300 lbf ft. Provide a calibrated torque wrench to demonstrate the adequacy of the bolt tightening, as approved by the Engineer. Where beveled ends on metal pipe are shown on the Plans or Standard Plates, cut the bevels at right angles to a vertical plane through the longitudinal axis of the pipe. C.3 Concrete Culvert Lay concrete pipe with the female end of each section upgrade. Tightly join the pipe sections so that the interior of the pipe sections abut each other. Use preformed rubber or bituminous mastic elastic joint sealer Material to provide flexible water-tight joint seals for concrete pipe. Where the pipe is designed to accommodate preformed gasket type seals, seal the joints with the preformed gasket as shown on the Plans and meeting the performance requirements of 3726, “Preformed Gasket Seals for Concrete Pipe.” Keep gaskets and joint surfaces clean and free from soil during installation . Follow manufacturer’s recommendation for fitting or coupling assembly and installation . Use a lubricant, if required, that will not deteriorate the gasket and pipe Materials . Where the pipe is not required to accommodate preformed gasket type seals, seal the joints with bituminous mastic and a full circumferential wrap of geotextile Material extending at least 1 foot on each side of the joint. Secure the circumferential wrap against the outside of the pipe by metal or plastic strapping or by other methods approved by the Engineer . Apply mastic joint sealer Materials as recommended by the manufacturer. Wipe joints clean on the inside after sealing. Plug lifting holes with a precast concrete plug, sealed and covered with mastic or mortar. Use approved fasteners shown on Standard Plate 3145 to tie together concrete Culvert sections unless otherwise shown on the Plans or specified in the Special Provisions.

Provide backfill Material in accordance with the Plan, modified to 100 percent passing the 3-inch Sieve within 2 feet of the pipe. C.4 Plastic Culvert Follow bedding, backfill, and trench width requirements shown in Plan. If cover over plastic pipe modified from what is shown in the Plan, follow plastic pipe minimum cover and maximum fill height requirements in the Drainage Manual . Provide backfill Material in accordance with the Plan, modified to 100 percent passing the 1-inch Sieve within 2 feet of the pipe. Use the embedment Material to provide 1 foot minimum of fill over the pipe for a trench width as specified by the C ontract. Place pipes and backfill in dry conditions by controlling the water conditions . Dewater groundwater and divert surface runoff to keep the water level below the pipe foundation. Place pipes on the bedding starting at the downstream end with the female end of each section upgrade. Make connections with bell and spigot joints using an elastomeric rubber seal (gasket) to provide water-tight joints that do not allow soil, Silt, or water to migrate through the joint. Install joints so connected pipe sections form a continuous surface free of irregularities in the flow line. Tightly join the pipe sections so that the interior of the pipe sections abut each other . Keep gaskets and joint surfaces clean and free from soil during installation . Follow manufacturer’s recommendation for fitting or coupling assembly and installation . Use a lubricant, if required, that will not deteriorate the gasket and pipe Materials. Before allowing vehicles or heavy construction Equipment to travel over the pipe trench, maintain a minimum cover depth of Material above the pipe of at least 2 feet and meeting the requirements of AASHTO LRFD Bridge Construction Specifications, Section 30, Table 30.6-1. Perform deflection testing of all plastic pipe at least 30 Calendar Days after installation. Remove obstructions such as sediment, standing water or safety grates that would interfere with deflection testing. Dewatering and additional Work associated with preparing for and performing deflection testing is included in the bid price of the pipe. Evaluate the pipe to determine if the specific internal diameter of the barrel has deflected more than 5 percent. Use the following methods to perform the deflection test unless specified in the Plan:

for pipes. Pull the mandrel through the pipe using non-mechanical means.

the Plans and approved by the Engineer. Direct measurements can only be used on pipes with an inside diameter of 30 inches or greater. If the Department allows direct measurements, the Engineer must take measurements at randomly select locations, but at a minimum once every 10 feet throughout the pipe length and at the pipe ends. Visually inspect the pipe and take additional measurements at any location of observed anomaly or deflection. Ensure personnel making direct measurements meet confined space entry requirements in accordance with 1706, “Employee Health and Welfare.”

when specified in the Plans and approved by the Engineer. The Engineer will not accept pipe that has a deflection of more than 5 percent or is damaged. Remove unacceptable pipe and reinstall new pipe or reuse undamaged pipe. Retest the relaid pipe for 5 percent deflection at least 5 Calendar Days after embedment Material is installed to grade. Send deflection testing results to the Hydraulic Engineer with the SP number, pipe location, Material type, size, date built, date tested, and results from the mandrel test or other deflection test. C.5 Extending In-Place Culverts Clear in-place Culverts of obstructions to water flow before placing the extension pipe. The Engineer will only require the removal of sediment to the extent that improved flow is likely to be maintained. Follow backfill and bedding requirements for Culvert Material type. If the pipe ends differ because of changed design, make the connection to the in -place Culvert as shown on the Plans or as approved by the Engineer. Extend cast-in-place concrete box Culverts with plant-fabricated pipe using the detailed connections as shown on the Plans. Use a transition section as shown on the Plans if extending a box-type concrete cattle pass with precast concrete sections. Expose the ends of the in-place Structure and remove concrete as shown on the Plans. Construct the cast-in-place portion of the transition in accordance with 2411, “Minor Concrete Structures.” D Backfilling Excavations Backfill excavations to the required extent shown on the Plans and at the appropriate time. Uniformly distribute suitable backfill Materials in 6 inch Layers. Compact backfill in accordance with the Plans and 2106, “Excavation and Embankment – Compacted Volume Method,” before placing successive Layers. Within the Road core, if the Contract does not specify special backfill Materials, use Materials meeting 3149.2D.1, “Granular Backfill,” placed within 18 inches of the sides and 12 inches above the top of the Structure (note that plastic Culverts require 1 inch minus Material, regardless of Culvert location). For the remainder of the backfill, use embankment Material meeting 1103, “Definitions: Select Grading Material.” If outside the Road core, use suitable Material meeting 1103, “Definitions: Select Grading Material.” Do not place backfill Material on a frozen foundation or when the Material may freeze during the placement or compaction Work. Step the sides of the excavation, if steeper than 1:4 and if potential wedging action of the backfill may be detrimental to the Structure. If the Contract does not require specific maximum dimensions for the excavation, the Contractor may enlarge the excavation and flatten the side slopes for convenience of backfill and compaction operations, at no additional cost to the Department. Backfill uniformly in horizontal Layers throughout the excavation area. Maintain the sides of the excavation and prevent voids in the backfill when removing shoring or bracing from the excavation.

E Culvert Appurtenances Provide and install appurtenant items such as aprons, safety aprons and grates, diaphragms, dissipator rings, flap gates, and safety grates, including special grates for concrete pipe and large size pipe, trash racks, and other similar devices requiring a special design, as shown on the P lans or the Special Provisions. F Induced Trench Installation Construct backfill over the Culvert, if shown on the Pans and in accordance with the following: Construct the embankment in accordance with 2106, “Excavation and Embankment – Compacted Volume Method,” for a width on each side of the installed Culvert at least equal to 3 pipe widths and to an elevation over the top of the Culvert equal to the pipe height plus 1 foot. When using 2106.3G.1, “Specified Density” method, compact the embankment to a density not less than 100 percent of Maximum Density. Excavate a trench to a level 1 foot above the top of the Culvert, for the width and length of the pipe, and with vertical sides. Loosely fill the trench with highly-compressible clay soil before constructing the remaining embankment in accordance with 2106, “Excavation and Embankment – Compacted Volume Method.” G Culvert Cleaning Clean sediment and debris from Culvert(s) before final acceptance. H Geotextile Use Geotextile 3733, Type 1 to wrap concrete pipe joints or for other drainage applications.

2501.4METHOD OF MEASUREMENT

A Culvert Excavation If the Contract contains separate items for Culvert excavation as specified in 2501.5, “Pipe Culverts, Basis of Payment,” the Engineer will classify and measure excavations for culverts in accordance with 2451, “Structure Excavations and Backfills.” B Culvert Pipe The Engineer will measure Culvert pipe by length, as determined by summation of the Nominal laying lengths of the individual pipe sections incorporated in eachS tructure. The Engineer will separate measurements by size, type, kind, and strength class in accordance with the item name. The Engineer will measure elbow, tee, and wye sections as pipe along the centerline of the Culvert barrel. The Engineer will not measure the length of branch legs, except as included in the measurements for a connecting Structure. The Engineer will measure transition sections as pipe of the larger or more costly size, except for special sections designated by the C ontact for measurement as a unit. The Engineer will measure the length of metal pipe installations requiring special fabrication, such as skewed or sloped ends, to the extreme ends including waste Material , unless otherwise shown on the Plans. Where pipe options are allowed, measurement will be made by length and type of pipe indicated on the Plan, regardless of the type of Material installed. No adjustments will be made for any additional Work required by the Contractor based on choice of Material.

C Culvert Appurtenances The Engineer will separately measure appurtenant items such as aprons, safety aprons and grates, diaphragms, dissipator rings, flap gates, grates, and other specially designed and identified units designated for payment on a per each basis by the number of units of each type and size incorporated in the Culvert structures. The Department considers a safety apron and grate as one unit. The Contract Unit Prices for pipe Culverts will include the cost of cast-in-place concrete Work. D Granular Materials The Engineer will measure granular Materials for special backfill or bedding in accordance with 2451.4B, “Granular Materials,” unless specified otherwise in the Plan.

2501.5BASIS OF PAYMENT

The Contract Unit Price for Culvert pipe of each size, type, kind, and strength class includes the costs of providing and installing the pipe complete in-place as required in the Contract, except as otherwise specified in this section. The Contract Unit Prices for plastic pipe Culverts will include the cost of deflection testing, dewatering, and buoyancy protection as required by the Plan but not designated under other items. Payment will not be made until proof of adequate deflection test is provided. The Department will separately pay for aprons, safety aprons and grates, safety grates, flap gates, dissipator rings, diaphragms, and other specially designed and identified appurtenant items by type, size, and number of units incorporated in the Structures as shown on the Plans. The Contract Unit Price for these items includes the cost of providing and installing the items complete in -place. The Department will separately pay for granular Materials for special backfill or bedding in accordance with 2451.5, “Structure Excavations and Backfills, Basis of Payment.” The Department will separately pay for Culvert excavation at the Contract Unit Prices included in the Contract in accordance with 2451.5, “Structure Excavations and Backfills, Basis of Payment.” If not included in the Contract, the Department will include excavating costs in the Contract Unit Prices for Culvert pipe and appurtenant items. Surplus excavated Materials not used for backfill become the property of the Contractor. Dispose of surplus Material in accordance with the disposal form submitted to and approved by the Engineer . The Contract Unit Price for the relevant Culvert Contract Item includes the costs associated with the disposal of surplus Material. The Department will provide additional compensation for Culvert elbows, tee or wye sections, and additional connectors directed by the Engineer, but not shown on the P lans, in the amount of the actual invoice cost of the Materials involved. The Department will pay for installing Culvert Materials provided by the Department under the applicable installation items shown in the Contract. The Contract Unit Prices for installing Culvert Materials provided by the Department include the cost of Work and additional Materials required for the installation complete in-place, except for Extra Work or Work designated under other items. If the Engineer allows installation by the jacking method and the Contract does not contain a relevant Contract Item, the Department will pay for a jacking installation on the basis of C ontract Unit Prices relevant for the trenching method. The Contract Unit Price for the relevant pipe Contract Item includes the cost of Culvert cleaning, except when specifically designated under other items.

The Department will identify when pipe Material options are allowed in the Plans. Payment will be made by the length and type of pipe indicated on the Plan, regardless of the type of Material installed. The Contractor will include the costs associated with using an alternative, such as differences in installation requirements including deflection testing, trench width , or embedment Material Specifications, and quantities in the Contract Unit Prices of the relevant pipe Pay Items. No adjustments will be made for any additional Work required by the Contractor based on the choice of Material. The Department will pay for pipe Culverts on the basis of the following schedule: Item No. Item Unit

2501.502 ___” ǁ Pipe Apron each

2 A-S Diaphragm for ‡ Pipe each

2 Flap Gate for ‡ Pipe each

2 ___” Span ǁ Pipe-Arch Apron each

2 A-S Diaphragm- for ‡ Pipe-Arch each

2 ___” ǁ Elliptical Apron each

2 ___” High ǁ Cattle Pass Transition Section each

2 ___ “ High ǁ Cattle Pass Apron each

2 ___” ǁ Safety Apron and Grate Design § each

2 ___” ǁ ** each

2 Install ** each

2 ___” RC Dissipator Ring each

3 Install ** linear foot

3 ___” ǁ Pipe Culvert † linear foot

3 ___” Span ǁ Pipe-Arch Culvert † linear foot

3 ___” ǁ Elliptical Pipe Culvert # linear foot

3 ___” High ǁ Cattle Pass Culvert † linear foot

3 ___” ǁ Struct Plate Pipe Culvert † linear foot

3 ___” Span ǁ Struct Plate Pipe-Arch Culvert † linear foot

3 ___” ǁ Pipe Culvert Design § † linear foot

3 ___” Span ǁ Pipe-Arch Culvert Design § † linear foot

7 Culvert Excavation Class * cubic yard

* Specify Class U, E, or R only – See 2451.3B.2, “Types” ǁ Specify Kind – See 2501.2, “Materials,” if alternatives are allowed do not specify kind † Specify Strength Class, if other than minimum requirement ‡ Specify size and kind # Specify HE or VE, and Strength Class, if other than minimum requirement § Give Standard Plate number for special pipe or joint designs ** Specify item name