2412Precast Concrete Box Culverts

2412.1DESCRIPTION

This Work consists of installing precast concrete box Culverts.

2412.2MATERIALS

2412.3CONSTRUCTION REQUIREMENTS

Install precast concrete box Culverts built in accordance with 2411, “Minor Concrete Structures,” 2451, “Structure Excavations and Backfills,” 3236, “Reinforced Concrete Pipe,” and 3238, “Precast Concrete Box Culverts” and the following: A Foundations Prepare foundations in accordance with 2451.3C, “Foundation Preparations,” except provide granular bedding in accordance with 3149.2F, “Granular Bedding,” and at least 24 inches thick. Use a template to shape the bedding to a flat base. Use a mechanical hand compactor to compact the bedding adjacent to the bottom corner radii. B Laying Precast Concrete Box Culvert Lay precast concrete box Culvert sections with the groove end of each section up-grade. Tightly join the sections. Use concrete pipe ties meeting the requirements of Standard Plate 3145 to tie individual sections together. Seal the joint on all four sides of the box Culvert with an approved product, as listed on the APL, Concrete, “Preformed Mastics,” per the manufacturer’s instructions. Place a strip of 3733,

“Geosynthetic Materials,” geotextile type 3 Material at least 24 inches wide centered over the top and sides of the joint. Use a minimum 12 inch lap between cut sections of the fabric. Clean the concrete to remove dirt by using a brush before applying the adhesive and fabric . Securely bond the fabric to the Culvert by applying adhesive to the Culvert or fabric for the full perimeter of the installed fabric. Prevent displacement of the geotextile Material during backfilling operations. Join the box sections so that when laid on the granular bedding, they form a smooth, uniform line of sections. Do not adjust the grade by exerting force on the box section with excavating E quipment or by lifting and dropping the box section. If the box section is not on the correct grade, unjoin the sections, correct the grade and rejoin the sections. Prevent construction Equipment loads greater than the loads used in the design to be transferred to the box section before, during, or after fill placement, either directly or through the fill. Use precast concrete plugs to plug lifting holes in the top surface. If lifting holes are located in the sidewall, completely fill the holes with mortar meeting 3107 “Masonry Mortar,” or cover the hole with bolts, nuts and washers meeting 3392, “Galvanized Hardware,” and large enough to completely cover both ends. After plugging, seal and cover lifting holes with an approved product, as listed on the APL under “Mastic,” or mortar.

2412.4METHOD OF MEASUREMENT

A Culvert Excavation If the Contract contains separate Pay Items for Culvert excavation, the Engineer will classify and measure excavation for concrete box Culverts in accordance with 2451.4A, “Structure Excavation.” B Precast Concrete Box Culverts The Engineer will measure precast concrete box Culverts by length. The Engineer will determine the length by adding the Nominal laying lengths of the individual sections incorporated into each Structure. The Engineer will take separate measurements for each Contract Pay Item size. The Engineer will measure transition sections between two different box C ulvert sizes as the larger or more costly size, except for special sections designated for measurement as each. C End Sections and Other Appurtenant Items The Engineer will separately measure end sections and other appurtenant items such as flap gates and other specially identified units, having Contract pay units described as “each,” by the number of complete units of each type and size incorporated into the box C ulvert structures. The Engineer will measure cast-in-place concrete Work, other than end sections and Culvert extensions, in accordance with 2411, “Minor Concrete Structures.” D Granular Materials The Engineer will not separately measure granular bedding for concrete box C ulverts. If the Contract includes Contract Pay Items for special backfill or bedding, the Engineer will measure special backfill or bedding for precast concrete box culverts in accordance with 2451.4B , “Granular Materials.”

2412.5BASIS OF PAYMENT

The Contract Unit Price for Precast concrete box Culvert and Precast concrete box Culvert end section will include the cost of providing and installing Culverts and end sections, excavations, lintel beams, drop-wall, foundation preparation, granular bedding Material, and backfill, unless the Contract includes separate Contract Pay Items for the Work. The Department will include the cost of cast-in-place concrete Work for extending an existing box Culvert with the adjacent precast box Culvert. The Department will include

the cost of the 6 inch granular bedding for Precast concrete box Culverts with the relevant Contract Pay Items for precast concrete box Culverts. The Department will pay for Precast concrete box Culverts on the basis of the following schedule: Item No. Item Unit

2412.502 ___ x ___ Precast Concrete Box Culvert End Section each

3 ___ x ___ Precast Concrete Box Culvert linear foot