709.01 714 SECTION 709 – RIPRAP AND SLOPE PAVEMENT
709.01 Description ................................ ................................ ................... 714
709.02 Materials ................................ ................................ ...................... 714
709.03 Classi fication ................................ ................................ ................ 716
709.04 Equipment ................................ ................................ .................... 717
709.05 Foundation Preparation ................................ ................................ 717
709.06 Rubble -Stone Riprap (Grouted) ................................ ................... 717
709.07 Sacked Sand -Cement Riprap ................................ ........................ 719
709.08 Reinforced Concrete Slope Pavement ................................ .......... 719
709.09 Machined Riprap ................................ ................................ .......... 720
709.10 Final Cleanup ................................ ................................ ............... 720
709.11 Method of Measurement ................................ .............................. 721
709.12 Basis of Payment ................................ ................................ .......... 721
DESCRIPTION
709.01 Description
Riprap consist s of furnishing and setting or placing rubble stones, crushed stone, sacked sand -cement, machined riprap, and embedded riprap. Slope Pavement consist s of constructing a reinforced concrete mat on prepared slopes. MATERIALS
709.02 Materials
To construct riprap and slope pavement, provide materials that meet the following:
A.Rubble-Stone Riprap For Rubble-Stone Riprap , provide stone or broken Class A or paving concrete meeting the requirements of 921.07. Ensure that at least 80% of the stone have a minimum di mension of 10 inches. The remainder 709.02 715 shall be 2 to 4 inches and shall be approximately rectangular or trapezoidal in shape. Broken Class A or paving concrete shall be free of steel and wire fabric reinforcement. For Rubble-Stone Riprap (Grouted), provide sand meeting 903.01 or
903.02 and cement meet ing 901.01.
B.Sacked Sand-Cement Riprap For Sacked Sand-Cement Riprap, provide manufactured or natural sand meeting the quality requirements of 903.01 or 903.02 and cement meeting 901.01. Use sacks of either cotton or jute, standard grade of cloth, that will hold the sand-cement mixture without leakage during handling and tamping. Sacks shall be strong and sized to hold approximately 1 cubic foot .
C.Reinforced Concrete Slope Pavement Construct r einforced concrete slope pavement of Class A concrete meeting 604.03 and steel reinforcement meeting 907.01 or 907.03, whichever is specified. Preformed expansion joint filler shall meet 905.01.
D.Curing Materials Provide materials meeting 913.
E.Machined Riprap For Machined Riprap , provide clean shot rock that is essentially free of sand, dust , and organic materials , and that is of the size designated for the class specified. The stone shall be uniforml y distributed throughout the size range. Construct the stone layer to the thickness designated for the specified class , as defined in 709.03, unless otherwise noted on the Plans. Provide washed or clean rock, at no additional c ost to the Department, for sensitive areas of the Project, as shown on the Plans, described in permits, or designated by the Engineer. Obtain the Engineer’s approval 709.03 716 of washed or clean rock before placing in environmentally sensitive areas. When using rock or stone as riprap, ensure that the material meets the quality requirements in 903.25. Obtain the Engineer’s approval of t he material before using.
709.03 Classification
Riprap is classified according to the following designations:
1.Rubble-Stone Riprap (Grouted)
2.Sacked Sand -Cement Riprap
3.Machined Riprap
a.Machined Riprap (Class A -1) shall vary in size from 2 inches to 1.25 feet with no more than 20% by weight being less than 4 inches. The thickness of the stone layer shall be 1.5 foot with a tolerance of 3 inches.
b.Machined Riprap (Class A -2) shall be identical to Class A -1 except that the Contractor may substitute hand placed rubble stone riprap pla ced 1 foot thick in accordance with 709.11 for 1.5 feet of machined riprap.
c.Machined Riprap (Class A -3) shall vary in size from 2 to 6 inches with no more than 20% by weight being less than 4 inches. The thickness of the 4 -inch stone layer shall be as shown on the Plans.
d.Machined Riprap (Class B) shall vary in size 3 inches to 2.25 feet with no more than 20% by weight being less than 6 inches. The thickness of the layer shall be 2.5 feet with a tolerance of 4 inches.
e.Machined Riprap (Class C) shall vary in size from 5 inches to 3 feet with no more than 20% by weight being less than 9 inches. The thickness of the layer shall be 3.5 feet with a tolerance of 6 inches. 709.04 717 EQUIPMENT
709.04 Equipment
Provide wooden or metal ta mps of sufficient weight and number to properly compact the slopes on which the riprap or slope pavement is to be placed. When using sacked sand -cement, furnish wooden hand tamps, having a tamping face not greater than 1 square foot, and of sufficient weig ht and number to properly tamp the riprap. Provide a mechanical mixer to mix concrete, cement grout, or sand -cement. Provide all necessary small tools or implements to perform the work. CONSTRUCTION REQUIREMENTS
709.05 Foundation Preparation
Immediately before constructing riprap or slope pavement, trim the slopes or ground surface within reasonably close conformity to the lines and grades shown on the Plans or as directed by the Engineer, and thoroughly compact the slopes or ground surface using hand or mechanical tamps. On slopes, place the bottom of the riprap at least 2 feet below the natural ground surface, unless otherwise directed by the Engineer.
709.06 Rubble-Stone Riprap (Grouted)
A.Placing Stone Construct Rubble -Stone Riprap (Grouted) by hand on the prepared foundation. Place the stones as close together as is practicable to minimize voids. When constructing rubble -stone riprap in layers, tie the layers together using large stones protruding from one layer into the other. Construct rubble -stone riprap to a standard depth of 12 inches, unless otherwise shown on the Plans or directed by the Engineer, but in no case to less than 10 inches in depth. Ensure that, for each 25 square feet of surface, Ru bble-Stone Riprap has an average depth of not less than the 709.06 718 depth shown on the Plans or as directed by the Engineer, or the standard depth required in these Specifications. Place each stone with the larger dimension parallel to the surface upon which it is set, except as set forth above to provide keys between layers. Place the length as directed by the Engineer, and set each main stone against the adjoining stones to provide close contact. Place stone so as to equally distribute the large stones to the e xtent possible. After a workable area of the riprap has been set, shape t he stones by knapping to a uniform surface . Thoroughly chink the voids and fill with the smaller stones and spalls. Continue this work as construction progresses.
B.Grouting After chinking and filling, fill the voids between the stones with grout. Take care to prevent earth or sand from filling the spaces between the stones before the grout is poured. To fill the voids, use grout composed of one part Portland cement and four parts san d, measured by volume, and mixed thoroughly with sufficient water to make a grout of a consistency that will flow into and completely fill the voids. Mix this grout either in a one -bag mixer or larger for not less than 1-1/2 minutes. Immediately before pou ring the grout, sprinkle the stones with water. Pour the grout carefully into the voids between the stones, beginning at the lower portions of the riprap and progressing upward. Ensure that the entire bottom line of voids is filled with grout before pour ing the line of voids next above. To pour the grout, use vessels of adequate size and shape. Broadcasting, slopping, or spilling of grout from the vessels on the surface of the riprap will not be permitted. Progress of pouring shall be sufficiently slow to prevent the grout from oozing from the voids and flowing over the surface. During the pouring operations and continuing until the grout has reached its initial set, use fiber brooms to maintain a uniform distribution. Continue the grouting operations until all the voids have been completely filled and the grout has set even with the surface of the riprap. 709.07 719 C. Curing As soon as any section of the grouted riprap has hardened sufficiently, sprinkle it with water until the riprap has been covered with burlap, cotton, or jute mates, earth, or liquid membrane -forming compound. Maintain the mats or earth by soaking with water for a period of not less than 72 hours. The water used for wetting and curing the grouted riprap shall be free from salt or alkali.
709.07 Sacked Sand -Cement Riprap
Construct Sacked Sand -Cement Riprap by placing sacks, filled approximately ¾ full of a mixture of sand and cement, on the prepared foundation. Mix the sand and cement dry, with a mechanical mixer, in the proportion of 94 pounds of cement to 5 cubic feet of dry sand, until the mixture is uniform in color. After the mixing has been completed, pour the sand -cement mixture into sacks, of approximately 1 -cubic foot capacity, until they are approximately ¾ filled. Securely fasten the sacks with hog rings, by sewing, or by using other suitable methods that prevent leakage of the mixture from the bags. Bed the sacks of sand -cement, by hand, on the prepared grade with all the fastened ends on the grade and with the joints broken. Th e completed riprap shall have a minimum thickness of 10 inches, measured perpendicular to the slope. The surface shall not vary more than 3 inches above or below the desired theoretical plane. Ram and pack the sacks against each other and tamp on the surf ace to form close contact and to ensure a uniform surface. Immediately after placing and tamping the sacks of sand -cement, thoroughly soak them by sprinkling with water. Do not apply water under high pressure. Before soaking with water, remove and replac e sacks of sand -cement that were ripped or broken during placing.
709.08 Reinforced Concrete Slope Pavement
Construct Reinforced Concrete Slope Pavement as shown on the Plans and in accordance with the applicable requirements of 604, except that the concrete shall be of such consistency that it will not flow on the slope and that will allow finishing to the thickness shown on the Plans. 709.09 720 Score or saw the slope pavement for a depth of 1 inch on 6 -foot center s, both ways, or as directed by the Engineer. Use a ½-inch preformed expansion joint filler wherever the slope pavement abuts a portion of the bridge sub - structure. Remove forms, which may be of wood or metal, after the concrete has set. Cure the concrete as specified in 501.18.
709.09 Machined Riprap
Take care in preparing the riprap subgrade to ensure that no reduction in the design waterway occurs. Do not place any riprap until the final subgrade elevation has been verified by the Engineer. When directed by the Engineer, roll the riprap down with metal tracked equipment to provide a more d ense stone mass with final contours in reasonable conformance to the Plans. Do not begin to place the super-structure until the Engineer has accepted the final elevation of the riprap. Upon completion of the work, visual ly inspect to ensure that approxima tely 50% of the surface area consists of stones no smaller than half of the maximum size specified. Dump and place t he material using appropriate power equipment in a manner that will produce a uniform surface appearance. Hand work may be required to correct irregularities. When preparing the site, adhere to the provisions for erosion control specified in 209 and for channel excavation specified in 203.02.C. When required by the Plans or permits, or as directed by the Engineer, properly tamp into the subsurface , or otherwise blend into the substrate , embedded riprap in streams, conveyances, diversions, or other sensitive areas. Ensure that water will flow over the embedded riprap and that flow is not lost below or within the rock. If clean rock is required by the Plans or permit, or as directed by the Engineer, provide rock that meets the provisions of 709.02 for clean rock.
709.10 Final Cleanup
Perform final cleanup as specified in 104.10. 709.11 721 COMPENSATION
709.11 Method of Measurement
The Department will measure Rubble -Stone Riprap (Grouted), Concrete Block Riprap, and Reinforced Concrete Slope Pavement by the volume in cubic yard, co mplete in place, as obtained from the thickness shown on the Plans and surface measurements. Unless otherwise specified, the Department will not measure or pay for reinforcement in slope pavement but will consider the costs thereof as included in the pric e bid for slope pavement. The Department will measure Machined Riprap by the ton or the cubic yard for the respective items in accordance with 109, complete in place. However, where Machined Riprap (Class A -2) is specified and the Contractor selects the hand placed rubble stone riprap option, the Department will increase actual tonnage measured and accepted by 50% for payment purposes. No measurement for payment will be made for excavation or for preparing the foundation fo r riprap, and filter blanket where specified.
709.12 Basis of Payment
The Department will pay for accepted quantities, complete in place, at the contract prices as follows: Item Pay Unit Rubble-Stone Riprap Cubic Yard or Ton Rubble-Stone Riprap (Grouted ) Cubic Yard Concrete Block Riprap Cubic Yard Reinforced Concrete Slope Pavement Cubic Yard Machined Riprap (Class __ ) Cubic Yard or Ton 710.01 722 SECTION 710 – UNDERDRAINS
710.01 Description ................................ ................................ ................... 722
710.02 Materials ................................ ................................ ...................... 722
710.03 Kinds and Sizes of Underdrains ................................ ................... 723
710.04 Reserved ................................ ................................ ....................... 723
710.05 Aggregate Underdrains ................................ ................................ 723
710.06 Aggregate Underdrains (with Pipe) ................................ .............. 723
710.07 Filter Cloth and Aggregate Underdrain (with and without Pipe) . 724
710.08 Final Cleanup ................................ ................................ ............... 725
710.09 Method of Measurement ................................ .............................. 725
710.10 Basis of Payment ................................ ................................ .......... 726
DESCRIPTION
710.01 Description
This work consists of constructing underdrains composed of stone, gravel, slag, sand, or any one of these ma terials and perforated pipe, semi -circular drain pipe (with connections), or filter cloth, on prepared foundations at the locations shown on the Plans or as directed by the Engineer. The work shall include all necessary excavation and backfill, together w ith such work and materials as may be necessary to make connections with other drainage structures, as shown on the Plans. MATERIALS
710.02 Materials
Provide materials as specified in: Aggregate for Underdrains ................................ .................... 903.17 Joint Mor tar ................................ ................................ ........... 905.02 Pipe (Size shown on the Plans) ....... 914.03, 914.07, 915.02, 915.03 Polyvinyl Chloride (PVC) Underdrain Pipe .......................... 914.09 Geotextile ................................ ................................ ............... 921.12
Source: Tennessee Standard Specifications for Road and Bridge Construction, 2021 Edition. Pages 723–730 of 1,072.