537 Concrete, Class A ........................................................ 702 Fine Aggregate, Size No. 23 ........................................ 904.02 Geotextile for Riprap ................................................... 918.02 Portland Ceme nt .......................................................... 901.01(b) Precast Concrete Riprap .............................................. 904.04(e) Riprap .......................................................................... 904.04 20 WWR, Smoot h ............................................................ 910.01(b)5 Water ........................................................................... 913.01 CONSTRUCTION REQUIREMENTS
616.03 Placing Dumped Riprap Dumped riprap shall be placed to produc e a surface of approximate regularity and
may not need to be hand placed. The finish ed surface shall vary no more than 9 in. from a true plane. The thickness perpendicular to its surface shall be no more than 2 ft nor less than 1 ft unless otherwise directed. 30
616.04 Placing Grouted Riprap The aggregate, preparation of the slope, and the depth of riprap aggregate for grouted riprap shall be in accordance with 616.05. After th e aggregate has been placed
and accepted, all openings shall be filled with cement grout. The finished surface shall be approximately smooth, solid, and true to line, grade, and section. Grout shall be composed of 1 part portland cement and 4 parts fine aggregate. The portland cement and fine aggregate shall be dry-mixed to a uniform mixture. Water shall be added as the mixing continues until the grout attains a consistency that will 40 enable it to flow into the openings. 616.05 Placing Revetment, Class 1, and Class 2 Riprap Revetment, class 1 and class 2 riprap may be placed by dumping and shall be placed to the required thickness. The fini shed surface shall be placed in a uniform manner and be free of segregated clusters. The finished surface shall vary from a true plane no more than 9 in. for revetment riprap or 18 in. for class 1 or class 2 riprap. The placed riprap shall not be less th an the minimum depth specified.
616.06 Placing Uniform Riprap 50
Uniform riprap shall be placed to produce a surface of approximate regularity with edges having projections no more than 3 in . above the required cross-section. The material shall be hand laid or placed by other approved means. 616.07 Blank
616.08 Placing Precast Cement Concrete Riprap
The slope on which the riprap is to be placed shall be in a ccordance with that shown on the plans unless otherwise designated. Placement shall begin in a trench below the toe of the slope and progress upward. Each piece shall be placed by hand 60 616.08 538 perpendicular to the slope. It shall be firmly embedded against the slope in such a manner that the vertical joint space between individual units does not exceed 3/8 in., unless otherwise specified. Half blocks, odd shaped blocks, or class A concrete shall be used to fill the voids at the ends of sections to be placed or on curved shaped sections. The top course shall conform, as nearly as practicable, with the prescribed berm or shoulder elevation. Any adjustment necessary to achieve this shall be obtained by constructing a wedge course near the top of the slope as directed. This wedge course, when required, shall consist of class A concrete. If the thickness of the course does not allow class A concrete, it shall be constructed of a 1:2 mortar proportioned by volume. Toewalls, when required, shall consist of class A concrete. 70
616.09 Slopewall The slope on which the slopewall is to be placed shall be in accordance with that shown on the plans unless otherwise designated.
The concrete mixture shall be class A. Where paved slopewall abuts or surrounds columns, piers, or other structures, 5/8 in. of asphalt joint filler shall be used between the slopewall and such structure. Welded steel wire reinforcement shall be placed within the middle 1/3 of the slopewall thickness unless otherwise directed. The fabric shall extend through all construction joints. The surface of the slopewall shall be cured 80 for 48 h in accordance with 501.20. Construc tion joints may be either butt or keyway type. Inspection holes shall be provided at the locations shown on the plans or as directed. The holes shall be approximately 3 ft by 3 ft in size. Precast concrete riprap, Type B, as shown on the plans, may be used in lieu of slopewall of 4 in. thickness. 616.10 Undermined Paved Side Ditch 90 Treatment of undermined existing paved side ditch and placement of revetment riprap shall be as shown on the plans or as otherwise directed. Undermined paved side ditch shall be broken up and left in place. If it is determined that erosion is excessive, the eroded area shall be backfilled with a cohesive material, compacted, regraded, and lined with revetment or uniform riprap.
616.11 Installation of Geotextile Under Riprap
Storage and handling of geotextiles shall be in accordance with the manufacturer’s recommendations. Geotextile shall be stored in such a manner as to prevent exposure 100 to direct sunlight, ultraviolet rays, water, temperature greater than 140°F, mud, dirt, dust, and debris. Each geotextile roll shall be labeled or tagged to provide product identification sufficient for inventory and quality control purposes. Exposure of geotextiles to the elements between lay down and cover shall be a maximum of 14 calendar days. If defects, rips, flaws, deterioration or damage incurred during manufacture, transportation, storage, or construction is evident at the time of 616.09 539 installation, the geotextile will be rejected and shall be replaced with no additional payment. The surface to receive the geotextile sh all be prepared to a relatively smooth 110 condition free of obstructions, depressions, and debris within the limits indicated on the plans. Geotextiles used along channels shall be placed with the machin e direction of the geotextile parallel to the channel. Successive geotextile sheets shall be overlapped in such a manner that the upstream sheet is placed over the downstream sheet and the upslope sheet over the downslope sheet. Geotextiles used for 2:1 or steeper slopes shall be placed with the machine direction of the geotextile sheets perpendicular to the toe of slope. The geotextile 120 sheets shall be overlapped in the direction of the anticipated movement of water. Adjacent pieces of geotextile may be joined by sewing if approved, or by overlapping and pi nning. The minimum overlap shall be 18 in. except when placed under water. When placed under water, the overlap shall be a minimum of 3 ft. Securing pins shall be steel, 3/16 in. in diameter, 18 in. long, pointed at one end and fabricated with a head to re tain a steel washer having an outside diameter of no less than 1 1/2 in. Securing pins with washers shall be inserted through both strips of overlapped geotextile at spacing intervals in Table 1 along a line through the midpoint of the overlap. The geotextile strip shall be placed so that the lower strip will be 130 overlapped by the next higher strip. Pins shall be driven until the washer bears against the geotextile and secures it firmly to the ground. Whether the fabric is joined by sewing or pinning, additional pins shall be installed as necessary to prevent any slippa ge of the fabric regardless of location. Slope Pin Spacing steeper than 3:1 2 ft 3:1 to 4:1 3 ft 4:1 or flatter 5 ft Table 1 The geotextile shall be placed in such a manner that placement of the overlying materials will not excessively stretch or tear the geotextile and will not pull the 140 required overlap or seam apart. Construction equipment shall not be on the exposed geotextile. Placement of riprap or stone shall start from the base of the slope, moving upslope and from the center outward. Riprap shall not roll downslope and the height of drop for riprap shall be kept to less than 2 ft.
616.12 Method of Measurement
Dumped, revetment, class 1, and class 2 riprap obtained from outside the right-of-way will be measured by the ton. If obtained from inside the right-of-way, no 616.12 540 measurement will be made if placed as s hown on the plans unless direct payment is specified. If placed at locations not shown on the plans, measurement will be made by 150 the square yard. Grouted riprap and precast concrete ripr ap, including the area occupied by the wedge course, will be measured by the square yard, parallel to the slope. Slopewall will be measured by the square yard. Holes for inspecting slopewalls will be measured per each. Geotextiles used under riprap will be measured by the square yard by the type specified, complete in place. Unifor m riprap will be measured by the ton. Treatment of undermined paved side ditch will be measured by the linear foot of paved side ditch, broken and left in place. 160
616.13 Basis of Payment
The accepted quantities of dumped, revetment, class 1, and class 2 riprap obtained from outside the right-of-way will be paid for at the contract unit price per ton. Dumped, revetment, class 1, and class 2 ripr ap obtained from within the project limits will be paid for at the contract unit price per square yard. Uniform riprap will be paid for at the contract unit price per ton. Grouted riprap will be paid for at the contract unit price per square yard of the specified de pth. Precast concrete riprap and concrete slopewall will be paid for at the contract unit price per square yard, all complete in place. If slag is used as dumped riprap and payment will be made per ton, the pay 170 quantity will be adjusted in accordance with 904.01. The accepted quantities of geotextiles used under riprap will be paid for at the contract unit price per square yard, complete in place. Inspection holes will be paid for at the contract unit price per each. The treatment of undermined paved side ditc h will be paid for at the contract unit price per linear foot for paved side ditch, break. Backfill required for treatment of paved side ditch will be paid for at the contract unit price per cubic yard for borrow, 180 cohesive. Payment will be made under: Pay Item Pay Unit Symbol Borrow, Cohesive ...................................................................... CYS Geotextiles for Riprap, _____ ................................................... SYS type Inspection Hole .......................................................................... EACH 190 Paved Side Ditch, Break ............................................................ LFT Riprap, Class _____................................................................... TON S Y S Riprap, Dumped ........................................................................ TON S Y S 616.13 541 Riprap, Grouted, _____ in. ........................................................ SYS depth Riprap, Precast Concrete ........................................................... SYS Riprap, Revetment ..................................................................... TON S Y S 200 Riprap, Uniform ........................................................................ TON Slopewall ................................................................................... SYS Slopewall, Concrete, _____ in. .................................................. SYS depth If the contract includes a pay item for removing materials from within the project limits which are used as grouted riprap, the cost of such removal shall be included in the cost of the pay item for the removal work . The cost of placing such material shall be included in the cost of the riprap pay item. The cost of placing grout in accordance with 616.04 shall be included in the cost of the grouted riprap item. The cost of paved side ditch required at the top of riprap and along the edge of riprap will be paid for in accordance with 607.06. The cost of welded steel wire reinforcem ent shall be included in the cost of the slopewall. The cost of excavation below the finished riprap or slopewall shall be included in 220 the cost of the riprap and slopewall pay items. The cost of excavation, grading, sewing, pinning, and necessary incidentals shall be included in the cost of geotextiles.