SECTION 415—CONCRETE SLOPE PROTECTION
415.01 Description
This work shall consist of furnishing and installing precast concrete blocks in a bed of coarse sand or installing a concrete slab on embankments at or near bridge abutments as shown on the plans or as specified by the Engineer.
415.02 Materials
a.Precast concrete blocks shall conform to Section 222.
b.Mortar shall be nonshrinking and shall conform to Section 218 as applicable.
c.Foundation course shall be Grading B sand conforming to Section 202 or approved local material similar in nature as approved by the Engineer.
d.Concrete shall be Class A3 conforming Section 217.
e.Welded wire fabric shall be No. 6 gage, 6 inches center to center each way, conforming to Section 223.
f.Herbicide shall conform to Section 244.
415.03 Procedures
a.Precast Concrete Block Slope Protection: The Contractor shall construct the subgrade at the required distance below the finished surface of the slope. Soft yielding sections and unsuitable 415.03 material shall be removed and replaced with useable subgrade material. The subgrade shall be compacted and shaped to a smooth, uniform surface. The foundation course shall be spread on the subgrade to a depth of 2 inches and treated with a Department approved highly insoluble soil sterilent herbicide. Material shall be in a dry form and have a maximum solubility rate of 250 parts per million. Material shall be uniformly applied at the maximum rate recommended by the manufacturer. The Contractor shall bed the blocks in the foundation course perpendicular to the finished surface in straight rows, with the longest dimension aligned horizontally. Blocks shall be placed with continuous joints extending horizontally on the face of the slope and with broken (staggered) joints extending perpendicular thereto, up or down the slope. Blocks shall be rammed until firmly seated and the surface conforms to the finished slope. Joints shall be filled with mortar. Cast-in-place edging for block slope protection shall be placed as specified in (b) herein.
b.Concrete Slab Slope Protection: The subgrade shall be prepared as for block slope protection. The cast-in-place concrete slab shall be 4 inches in thickness and shall be placed in accordance with Section 414.03(i). Except at railroad grade separations, the Contractor may provide a combination concrete slab and stone slope protection in lieu of the specified concrete slab slope protection. Protection shall be in accordance with the following:
1.Concrete portions, consisting of a paved ditch and a strip of concrete approximately 3 feet in width placed on the berm along the face of the abutment, shall be furnished as required for concrete slab slope protection. Stone shall be placed at a depth of 7 to 9 inches over the remaining area to be covered with slope protection.
2.The Contractor shall prepare the subgrade for concrete and stone in accordance with Section 414.03(i). The portion of the slope to be protected with stone shall be treated with a herbicide in accordance with (a) herein. Care shall be taken to confine application to areas designated for sterilization.
3.Stone shall be crushed gravel or stone conforming to Section 204.02 (b). Gradation of aggregate shall not be smaller than the sizes specified in Table II-3 for aggregate size No. 1 nor larger than 8 inches in their greatest dimension. Stone shall be in a sufficient range of sizes to create a stable (choked and locked) and reasonably uniform slope. The condition of the subgrade and method of placing stone shall be such that pieces of stone in contact with the subgrade shall be partially embedded where practicable. Stone immediately adjacent to concrete shall not project more than 3 inches above the concrete. Engineer approved splash blocks connecting with the paved ditch shall be provided under downspouts draining onto the slope protection.
415.04 Measurement and Payment
Concrete slope protection will be measured in square yards of surface area and will be paid for at the contract unit price per square yard. If limits are not shown on the plans, measurements will be taken from 415.03
Referenced in this section
Sections that cite this one
Concrete Slope Protection in other states
Get an email when 415 changes
Virginia revises spec sections through supplementals and new editions. We check this one every week and email you the day it changes. Free, no account.
Source: Road and Bridge Specifications, 2020 Edition. Pages 613–614 of 1,065. View official source ↗