204.01 153 SECTION 204 – STRUCTURE EXCAVATION FOUNDATION PREPARATION, AND BACKFILL
204.01 Description ................................ ................................ ................... 153
204.02 Classification ................................ ................................ ............... 153
204.03 Foundation Fill Material ................................ .............................. 155
204.04 Bedding Material ................................ ................................ ......... 155
204.05 Reserved ................................ ................................ ....................... 155
204.06 Backfill Material ................................ ................................ .......... 155
204.07 Reserved ................................ ................................ ....................... 158
204.08 Excavation ................................ ................................ ................... 158
204.09 Protection of Excavation ................................ .............................. 160
204.10 Foundation Preparation ................................ ................................ 161
204.11 Backfilling ................................ ................................ ................... 163
204.12 Method of Measurement ................................ .............................. 165
204.13 Basis of Payment ................................ ................................ .......... 169
DESCRIPTION
204.01 Description
This work consists of excavation, foundation preparation, and backfill for the installation or construction of bridges, culverts, underdrains, and other structures not otherwise provided for in the Specifications. This work also includes constructing and subsequently removing all bracing, shoring, cribbing, and cofferdams, all pumping and bailing, backfilling, and disposing of excess or unsuitable material.
204.02 Classification
The Department will classify and pay for Structure Excavation and Foundation Preparation under the following designations: 204.02 154 A. Culvert Excavation (Unclassified) Structure Excavation and Foundation Preparation performed within the limits specified in 204.08 and 204.10, for all box bridges, pipe culverts, sewers, conduits, all other culverts, all minor structures of any type and description, will not be measured and paid for directly but the cost will be incidental to other items, unless otherwise shown on the Plans.
B.Dry Excavation (Bridges) Structure Excavation and Foundation Preparation performed above the datum line (established by elevation and definitively shown on the Plans) and within the limits specified in 204.08.A and 204.10.A and not classified as Rock Excavation (Bridges), as indicated or directed, will be classified and paid for as Dry Excavation (Bridges).
C.Wet Excavation (Bridges) Structure Excavation and Foundation Preparation performed below the datum line (established by elevation and definitively shown on the Plans) and within the limits specified in 204.08.A and 204.10.A and not classified as Rock Excavation (Bridges), as indicated or directed, will be classified and paid for as Wet Excavation (Bridges).
D.Rock Excavation (Bridges) Structure Excavation and Foundation Preparation pe rformed either above or below the datum line (established by elevation and definitively shown on the Plans) and within the limits specified in 204.08.A and
204.10 A and consisting of material which cannot be economically
excavated without the use of explosives, also any boulder, slab, or fragment of rock having a volume of not less than 1/2 cubic yards, all Portland cement concrete, all masonry (dry mortar), as indicated or directed, will be classifi ed and paid for as Rock Excavation (Bridges). Cemented gravel, cemented chert, soft shale, or soft slate, even though requiring the use of explosives for economical excavation, will not be classified as rock.
E.Bridge Excavation (Unclassified) Bridge Excavation (Unclassified) shall be structure excavation and foundation preparation performed either above or below the datum line 204.03 155 (established by elevation and definitively shown on the Plans) as stipulated in 204.08.A and 204.10.A regardless of the nature of the material excavated.
F.Rock Drilling (Brid ges) Rock Drilling includes the drilling or sinking of test holes through or in rock to verify the condition of the foundation. MATERIALS
204.03 Foundation Fill Material
Material for foundation fill shall consist of suitably graded sand, gravel, slag or stone, as approved by the Engineer.
204.04 Bedding Material
A.Support for Pipe Culverts For Class A bedding, use Portland Cement Concrete, Class A meeting 604. For Class B bedding, use sand or a natural sandy soil, all of which passes a 3/8-inch sieve and not more than 10% passes a No. 200 sieve, or a Type A or Type B Aggregate, Grading C, D, or E meeting 903.05.
B.Areas Requiring Free Drainage Material In rock cuts or other areas designated by the Engineer that require a free drainage bedding or backfill material, provide crushed stone, crushed slag, or washed gravel meeting 903.17.
204.05 Reserved
204.06 Backfill Material
A.General Material for backfill shall be fine compatible soil selected from structure excavation if approved by the Engineer as being suitable. Obtain 204.06 156 additional material needed from r oadway or borrow excavation as specified in 203. Granular Backfill Material for Structures shall be Type A aggregate, Grading D meeting 903.05.
B.Flowable Fill If shown on the Plans, place as backfill mater ial a controlled low strength material (CLSM) (flowable fill) at the locations shown on the Plans or as directed by the Engineer. Materials used in the placement of CLSM shall meet the following requirements: Portland Cement, Type I ................................ ........................ 901.01 Fine Aggregate ................................ ................................ ....... 903.01 Water ................................ ................................ ...................... 921.01 Chemical Admixtures and Additives ................................ ..... 921.06 Air Entraining Admixtures ................................ ............. 921.06.A.2 Fly Ash, Class C or Class F ................................ ................... 921.15 Ground granulated blast furnace slag (GGBFS) .................... 921.16 Submit for approval a proposed mix design for CLSM as specified in 604.03. As defined herein, there are t hree types of CLSM: general use flowable fill, excavatable flowable fill, and early strength flowable fill. As part of acceptance testing, the Department will determine the consistency of CLSM in accordance with the procedure described below. This method applies to each of the types of CLSM.
a.Place an inverted slump cone on a smooth, level surface.
b.Fill the inverted slump cone with a representative sample of the flowable fill without rodding in one lift .
c.Remove the slump cone by lifting it straight up , thus allowing the sample to diffuse on the smooth, level surface. 204.06 157 d. The flowable fill should diffuse into a circular shape having an approximate diameter of not less than 15 inches. Each consistency test will represent up to 100 cubic yards of flowable fill at each installation. The Engineer may adjust the Specification Li mits identified below to obtain the consistency required for satisfactory flow.
1.General Use Flowable Fill. When not otherwise shown on the Plans, or specified in the Contract, provide general use flowable fill proportioned to meet the consistency of a 1 5-inch minimum spread.
2.Excavatable Flowable Fill (EFF). If shown on the Plans, design, proportion, and deliver to the Project an EFF that meets the performance requirements specified in Table 204.06 -1. Table 204.0 6-1: Specification Limits for EFF Property Specification Limit Air content (ASTM D 6023) Maximum 30% (1) Consistency 15 inches minimum as tested per
204.06 B
Compressive strength (ASTM D 4832) (2) 30 psi minimum at 28 days 100 psi maximum at 28 days
1.When using air entrained mixture design
2.ASTM D4832 4 x 8 inch cylinder molds may be used. The preferred c apping method to be used is wet suit neoprene restrained in rigid retainers. The Contractor may adjust the mixture design with the Engineer’s approval to obtain the required properties.
3.Early Strength Flowable Fill (ESFF). If shown on the Plans, design, proportion, and deliver to the Project ESFF that meets the performance requirements specified in Table 204.06 -2. 204.07 158 Table 204.0 6-2: Specification Limits for ESFF Property Specification Limit Air content (ASTM D 6023) Maximum 30% (1) Consistency 15 inches minimum as tested per
204.06 B
Compressive strength (ASTM D 4832) (2) 30 psi minimum at 24 hours
1.When using air entrained mixture design .
2.ASTM D4832 4 x 8 inch cylinder molds may be used. The preferred c apping method to be used is wet suit neoprene restrained in rigid retainers. Include in the proportions of ESFF sufficient amounts of cementitious materials, high range water reducers, accelerators, and other chemical admixtures so the ESFF can be loaded/backfilled as specified. The Contractor may adjust the mixture design with the Engineer’s approval to obtain the required properties.
4.Provide an approved Concrete Daily Report, and furni sh the resources, information, and tools that will meet the requirements of
501.03 B. To produce the desired consi stency, the Contractor may
use chemical admixtures , air entraining a dmixtures, or both, at no additional cost to the Department.
204.07 Reserved
CONSTRUCTION REQUIREMENTS
204.08 Excavation
A.Bridges, Box Culverts , and Other Major Structures Before the start of excavation, the Engineer, or Contractor when required, will set stakes locating and outlining the structure and cross - section for excavation computations. 204.08 159 Before star ting excavation, clearly mark the limits of disturbed area and undisturbed area using highly visible markers that are readily visible to project personnel including equipment operators. Excavate to the lines an d elevations shown on the Plans or as direct ed by the Engineer. The Engineer will allow working variations outside the neat lines; however, the Department will only measure that excavation specified in 204.12 for payment. Do not deposit or dispose of any excavated materia ls outside the construction lines unless directed and approved by the Engineer according to the manual Procedures for Providing Offsite Waste and Borrow on TDOT Construction Projects . If solid rock is encountered in roadway cut sections and channel section s under bridges, perform presplitting operations as specified in 203.04.C. Hole spacing along bridge abutment sites shall not exceed 12 inches. If overshooting of rock beyond the cut sec tions shown on the bridge plans requires modification of bridge abutments or span lengths, make such modifications at no additional cost to the Department. Excavate inclined surfaces of rock used as foundation either level or in steps. When necessary to obtain good bond, as determined by the Engineer, roughen the surface of rock foundation or install suitable anchors. Over-excavations that require re -design, increased bridge length, increased quantities, supplemental retaining walls or other earth retaining structures, shall be at no addition al cost to the Department. Remove existing concrete foundations, boulders, or ledge streaks of rock projecting into the bottom of the excavation to a depth of 6 inches below foundation elevation. Backfill and compact the resulting cavity with approved mat erial. Only excavate below the specified bridge foundation elevations as directed by the Engineer. Replace, at no cost to the Department, all materials moved without such authority by constructing a sub -footing of the same materials as the footing of the structure unit and 6 inches wider on every side.
B.Pipe Culverts Excavate for pipe culverts as specified in 204.08.A and as follows: 204.09 160 1. The width of the pipe trench shall be as shown on the P lans to allow satisfactory join ing of the pipe, thorough tamping of the bedding material under and around the pipe, and placement of flowable fill.
2.Remove rock, hardpan, or other unyielding material encountered in the pipe trench to below the foundation grade for a depth of 6 inches, or as directed by the Engineer.
C.Use of Excavated Materials Use suitable excavated material as backfill or embankment. When disposing of excess or un suitable material, do not obstruct the stream or otherwise impair the efficiency or appearance of the structure. Deposit excavated material so as not to damage a partly finished structure. Carefully handle, deposit, and protect excavated materials that wi ll be incorporated in the structure. In streams, dispose of material according to the laws of the U.S. Government, the requirements in the TN Construction General Permit, and all other applicable environmental permits.
204.09 Protection of Excavation
Protect excavation areas and ensure that the excavation remains intact. If OSHA regulations require shoring, submit to the Engineer, prior to starting work, computations and drawings, prepared by and stamped by a P rofessional Engineer licensed in the State of Tennessee, showing the basis for the design. If using cofferdams or cribs for foundation construction, ensure that they are carried to sufficient depths below the bottom of the foot ings, are substantially braced in all directions, and are as watertight as necessary for proper performance of the work. When dewatering work areas, comply with the requirements of the TN Construction General Permit, and do not violate water quality stan dards. Unless otherwise shown on the Plans, construct cofferdams so that the interior dimensions provide sufficient clearance for the construction and inspection of forms, and to allow for pumping of leakage outside of the footing area. If cofferdams or cribs tilt or move out of position during the process of sinking, right, reset, or enlarge them to provide the necessary clearance at no additional cost to the Department. 204.10 161 Construct cofferdams or cribs to protect the foundation and the construction therein against damage from a rise in the stream. With the Engineer’s written permission, obtained before the start of cofferdam or crib construction, the Contractor may extend timber, or bracing of a cofferdam or crib, into or through the substructure. Do not brace the cofferdams for structure widening off of the existing structure. Before starting any work, submit drawings to the Engineer, prepared and stamped by a Professional Engineer licensed in the State of Tennessee, showing details of the proposed coffe rdam or crib construction. The type and clearance of cofferdams, or cribs, insofar as they affect the finished structure or part thereof, will be subject to the Engineer’s approval, but the design and successful construction of cofferdams or cribs is the Contractor’s responsibility. Do not begin work in a stream without receipt of the applicable permits from State and Federal agencies. Ensure that cofferdam construction is in accordance with all permit requirements. Unless otherwise directed, r emove coff erdams or cribs, with all falsework, sheeting, bracing, and related appurtenances, after completing the sub - structure therein, unless otherwise directed. Complete the removal without disturbing or marring the completed work. If the foundation excavation b ecomes disturbed or distorted, clean out and restore it to satisfactory condition at no additional cost to the Department.
204.10 Foundation Preparation
A.Bridges, Box Culverts , and Other Major Structures Prepare foundations for bridges, box culverts, and other major structures according to the following:
1.After completing the foundation preparation to the specified elevation, notify the Engineer and await the Engineer’s inspection and approval before resuming construction therein.
2.When directed by the Engineer, unless piles are indicated, test each foundation in the presence of the Engineer by sinking three to six test holes to a depth of between 6 and 10 feet. 204.10 162 If these test holes reveal unsatisfactory foundation conditions, continue the excavation lower, as directed by the Engineer, and conduct new tests until a satisfactory foundation is obtained.
3.If rock is encountered in the excavation for the foundation, remove loose fragments and debris and notify the Engineer. Drill test holes in the rock as shown on the Plans or as directed by the Engineer to determine the lines of demarcation, the classification, and the stability of the rock. Continue the excavation to the elevation designated by the Engineer. If required by the Engineer, drill test holes and continue excavation until a foundation approved by the Engineer is secured. Strip and clean rock used a s foundation of all overlying materials. Remove all loose, disintegrated, or light slabby portions of the rock. In rock foundations, if the rock is shattered below the foundation elevation, remove the shattered material and rebuild the resulting space with the same type of construction as the proposed overlying construction, at no additional cost to the Department.
4.If the Plans require driven piles, or if after the foundation excavation has been completed it becomes necessary to reinforce the foundation by driving piles, remove any resulting bulges of the foundation material, at no additional cost to the Department , to the elevation indicated or directed, and bring the foundation to an even surface over its entire area.
5.Remove unsatisfactory material in the foundation and replace with satisfactory material designated by the Engineer. Place the satisfactory material in layers not exceeding 6 inches in loose depth and compact to 100% of maximum density up to the foundation elevation.
6.If pumping from the interior of a foundation enclosure, prevent the possibility of concrete material being carried away. Use a suitable sump located outside the concrete forms to perform any pumping required during the placing of concrete, or for a period of at least 24 hours thereafter. When dewatering work areas, comply with the requirements of the TN Construction General Permit, and d o not cause a water quality violation. 204.11 163 7. If conditions make it impracticable to dewater the foundation before placing the footing, the Engineer may allow the Contractor to construct a concrete foundation seal of the dimensions and thickness necessary to resi st possible uplift.
a.Before pouring the seal, clean the foundation of all objectionable material using sand pumps, spud bars, or other suitable means.
b.Construct the seals as specified in 604.18.
c.Allow the seal to set sufficiently to withstand the hydrostatic pressure before starting pumping for dewatering operations.
d.Dewater the foundation and thoroughly clean the seal of all laitance and ensure that it is generally prepared for further construction.
B.Pipe Culverts Bedding and trench installation shall conform to the requirements in the Standard Drawings, Specifications, or the Plans. Pipe Culvert shall be placed into an excavated trench. When existing embankment areas are not available to excavate for a trench, follow guidance in Standard Drawings for induced trench method. Bedding for plastic pipe shall be Class B, Type A or B Aggregate, Grading D or E meeting 903.05. If placing bell and spigot pipe, dig recesses in the bedding material of sufficient width and depth to ensure that the bell will not rest on the bottom of the recess. The width of the recess shall not exceed the width of the bell by more than 2 inches . If the class of bedding is not sho wn, cut a shallow trench in natural ground or compacted embankment to a depth of not less than 10% of the outside vertical pipe diameter, and shape to fit the lower pipe exterior for the specified embedment. If placing bell and spigot pipe culvert, dig recesses in the earth foundation of sufficient width and depth to ensure that the bell will not rest on the bottom of the recess. The width of the recess shall not exceed the width of the bell by more than 2 inches.
204.11 Backfilling
Place all backfill, o ther than flowable fill, which will become a part of the roadway prisms or their foundations, in layers, and compact to the density as 204.11 164 specified in 205.04, Standard Drawings, or the Plans . Place flowable fill, if called for on t he Plans, as specified in 204.06.B.
A.Bridges, Box Culverts, and Other Major Structures Backfill all exca vated areas not occupied by structures with acceptable earth material to the normal ground surface, unless otherwise directed. Place backfill in layers, not more than 6 inches in loose depth for mechanical tamps and 10 inches in loose depth for tamping ro llers, on both sides of the structure or around the structure unit, maintaining the layers at equal elevation and thoroughly compacting each layer by tamping with suitable rapid -striking power -driven mechanical tampers or sheepsfoot rollers before placing the succeeding layer. Place Granular Backfill Material for Structures ( Type A, Grading D) meeting 204.06, so that the compacted depth does not exceed 6 inches per layer. Compact every 6 -inch layer to 100% density. If any part of the structure is to function as a retainer for backfill, such as abutments, retaining walls, wing walls, arches, side walls of box culverts, or minor structures, step the boundary slopes as necessary to prevent wedge action during backfilling. Do not place backfill against a structure or any section or unit thereof, until the following conditions have been met:
1.Forms have been removed and concrete surfaces have been finished as specified in 604.21 and 604.22, respectively;
2.Representative specimens of the structural concrete, cured by the same methods and in the same manner as the co ncrete in the structure, attain a compressive strength of 3,000 psi; and
3.The concrete has been in place a minimum of 7 days, not counting the days of 24 hours each in which the temperature falls below 40 °F, or 21 calendar days, whichever occurs first. When backfilling behind abutments held at the top by a superstructure, and behind the sidewalls of culverts, bring up backfill simultaneously behind abutments or sidewalls. Promptly backfill box culverts and bridge ends after the strength requirements have been met, but no longer than 30 days following 204.12 165 strength attainment, and before placing a bridge deck, or as directed by the Engineer.
B.Pipe Culverts After the bedding has been prepared and the pipe culvert installed; place backfill and embankment uniformly as shown in the Standard Drawings, Specifications, or Plans. Compact mat erial with mechanical tampers to the required density. Above the top of a backfilled trench, place embankment as specified in the applicable section of 205, except for those requirements related to the induced trench method. Backfill for plastic pipe culvert shall be Class B, Type A or B Aggregate, Grading D or E meeting 903.05. Use vibratory plate type compactor s to achieve required density. Do not use hydrohammer compactors over the top of the pipe culvert. Engineer shall approve compaction equipment.
C.Backfill Material (Flow able Fill) Place Excavatable F lowable Fill at the locations shown on the Plans or as directed by the Engineer. Cover or otherwise protect the flowable fill while in the plastic state. Do not place embankment or base materials on the flowable fill prior to final set or hardening as determined by the Engineer. Before placing flowable fill, install pipe and bedding as shown on the Plans and Standard Drawings . Securely brace or anchor all sections of pipe both horizontally and vertically , as required , to prevent movement of the pipe during placement of the flowable fill. Join pipe sections to prevent the influx of flowable fill around the joints. Replace, at no cost to the Department, all pipe or sections of pipe that cannot withstand placement of flowable fill. Make provisions to form up, or provide earthen berms, to prevent the flowable fill from escaping at the ends of the trench and around headwalls. COMPENSATION
204.12 Method of Measurement
The normal ground surface, as used in th is Section, is defined as the bottom of channel excavations when channel excavation is indicated in the contract documents, the template section of the roadway in cuts, or the natural ground surface, whichever is at the lower elevation. When structure exc avation is 204.12 166 required in new embankment, the normal ground surface shall be the planes of the new embankment at the elevation specified or directed for construction in advance of performing the required structure excavation, but in no case shall the normal g round surface be above the planes of the new embankment.
A.Structure Excavation
1.The Department will measure structure excavation by the cubic yards of material in its original position only.
2.The Department will measure excavation necessary to construct box bridges, box culverts, retaining walls or minor structures, including pipe culverts and sewers, as follows:
a.Unless otherwise shown on the Plans, no allowance will be made for excavation, except that undercutting for these structures made at the dir ection of the Engineer to remove unsuitable foundation material will be classified and paid under the item for Undercutting, in accordance with 203.10.
b.If the Plans provide for direct payment of excavation, the excavation, inc luding undercutting made at the direction of the Engineer to remove unsuitable foundation material, will be classified and paid for as Culvert Excavation (Unclassified) with the following exception: Excavation within the limits of box bridges, box culverts with a bottom width between the inner faces of the outside walls greater than 14 feet, that is performed above the flow line of the structure, and with a bottom width equal to the distance between the inner faces of the outside walls on a 1:1 slope to the normal ground surface, will be m easured and paid for under the i tem for Channel Excavation (Unclassified).
3.If the Plans provide for direct payment of excavation, the Department will measure the actual volume of material excavated, provided it does not extend beyond the following limits of excavation:
a.For box bridges, box culverts, retaining walls or minor structures, including pipe culverts and sewers, the volume of Culvert Excavation (Unclassified) measured will extend horizontally to the vertical p lanes located 18 inches outside the 204.12 167 neat lines of the section of the structure at foundation elevation, as indicated or directed, and vertically between the normal ground surface and the foundation elevation, as approved. For box bridges and box culverts without bottom slabs, the foundation elevation is considered to be the bottom of footings and the flow line elevation between footings. No allowance will be made for overlapping areas.
b.Where internal forming is required , as for cut off walls and similar features, the quantity measured will extend horizontally 12 inches outside the neat lines of the completed work and vertically from the foundation elevation to the bottom of the completed excavation.
c.For pipe culverts, the volume of Culvert Excavation (Unclassified) measured will extend vertically between the normal ground surface and the bottom of the excavation for the pipe, as approved, and horizontally to not beyond two vertical planes separated by a horizontal distance equal to the outside diameter of the pipe plus 3 feet.
d.Where rock removal is necessary to prepare a satisfactory bed for pipe culverts, the quantity removed will be measured to a depth of 6 inches below the bed of the pipe, as approved. No allowance will be made for the material used in backfilling, except bedding material when specified.
e.The volume of Dry Excavation (Bridges), Wet Excavation (Bridges), Rock Excavation (Bridges), and Bridge Excavation (Unclassified) measured will extend vertically between the normal ground surf ace and the bottom of the excavation as approved, and horizontally to the vertical planes located 18 inches outside of the neat lines of the section of the structure at foundation elevation. Where a concrete seal is used, the limits of excavation will not extend beyond the neat lines of the concrete seal, as specified or as directed by the Engineer .
f.For excavation necessary to form struts, diaphragms, beams, and similar features , the volume measured will extend vertically between the normal ground surfa ce and a horizontal plane located 12 inches below the members, and horizontally to the vertical planes located 18 inches beyond the limits of the members. 204.12 168 4. No increase or decrease in payment will be allowed for changes in amount of excavation due to the shifting of location of str uctures from that shown on the P lans or for the addition of structures to those shown on the Plans when the Plans do not indicate that direct payment will be made for this excavation. Further, if this area of excavation, namely 18 inches horizontally outside of the neat line of the structure at foundation elevation, overlaps an area in which the excavation is computed on a separate unit price, the excavation in the overlapping area will not be allowed.
5.The Department will meas ure extra excavation below foundation elevation, as shown on the Plans or as directed by the Engineer, if due to causes not attributable to the Contractor’s actions. In computing extra depth excavation, the working limits established herein will be adher ed to.
6.No allowance will be made for shaping necessary to accommodate the bells of the pipe.
7.The Department will measure Rock Drilling performed as specified in 204.10.A by the linear foot.
B.Protection of Excavation
1.If items for cofferdams or cribs for individual piers or bents are provided by the Plans, the Department will measure this work in individual lump sum items for the pier or bent designated.
2.If a bid item for sheet piles is provided on the Plans, the Department will measure and pay as specified. If payment for the sheet piles is by the square foot, the Department will measure based on the as - designed sheet pile length to retain and counteract lateral earth forces, plus 1 foot.
C.Bedding and Backfill
1.If payment for bedding is provided on the Plans, the Department will determine the volumes of Class A and Class B bedding based on the theoretical quantity, in cubic yards per foot of pipe, as shown on the Standard Drawings or Plans. 204.13 169 2. The Department will measure Back fill Material ( Fl owable Fill ) based on the theoretical quantity in cubic yards, as shown on t he Standard Drawings. Measurement will be made along the centerli ne of the pipe for the width of trench shown on the Plans.
3.Material used to replace appr oved undercuttin g for box bridg es, box culverts, retaining walls or minor structures, including pipe c ulverts and sewers, will be paid under the item for Foundation Fill Material, and the measurement will be the same quantity as the approved undercutting it replaces. The Department will not measure for payment:
1.Materials moved from their original position before being measured by the Engineer;
2.Slides, cave-ins, and excavation extending outside of the wo rkable limits;
3.Removal of foundation material that has bulged due to driving piles;
4.Excavation above the normal ground surface, unless otherwise shown on the Plans;
5.Water and its removal; and 6. Construction and/or removal of cofferdams, cribs, sheet pile s, or other protective measures provided to safeguard an excavation, unless otherwise shown on the Plans.
204.13 Basis of Payment
If provided for on the Plans, t he Department will pay for accep ted quantities at the contract prices as follows: Item Pay Unit Culvert Excavation (Unclassified) Cubic Yard Dry Excavation (Bridges) Cubic Yard Wet Excavation (Bridges) Cubic Yard Rock Excavation (Bridges) Cubic Yard Bridge Excavation (Unclassified) Cubic Yard 204.13 170 Extra Depth Structure Excavation and Foundation Preparation Cubic Yard Rock Drilling (Bridges) Linear Foot Bedding Material (Pipe) Class A Cubic Yard Bedding Material (Pipe) Class B Cubic Yard Cofferdam Lump Sum Foundation Preparation Lump Sum Backfill Material (Flow able Fill) Cubic Yard Such payment is full compensation for providing all materials, equipment, labor, and incidentals to complet e the work as specified, inclu ding performing embankment construction, sloping, shaping, dressing, disposal of excess or unsuitable mate rial, and final cleanup. The Department will pay for Structure Excavation and Foundation Preparation of the various classes based on the volume computed i n accordance with 204.12.
A.Extra Depth Structure Excavati on and Foundation Preparation The Department will pay for Extra Depth Structure Excavation an d Foundation Preparation, classified as Culvert Excavation (Uncla ssified), made necessary by the Engineer establishing the foundation belo w the elevation shown on the Plans, at the contract unit price per cu bic yard for Culvert Excavation (Unclassified). Extra Depth Structure Excavation and Foundation Preparation for bridges made necessary by the Engineer requiring excavation bel ow the foundation elevation shown on the Plans, will be paid for at the contract price per cubic yard for Dry Excavation (Bridges), Wet Excavati on (Bridges), Rock Excavation (Bridges), as classified for the act ual quantity in cubic yards, excavated from the designated zone, th is zone being between the elevation shown on the Plans and the final ap proved elevation, as directed by the Engineer, plus the additional per centages for each zone corresponding to the depths lowered below Plan el evation as specified in Table 204.13-1. 204.13 171 Table 204.13 -1: Designated Zone for Extra Depth Structure Excavation Sub-Item Designation Zone No. Depth Lowered below Plan Elevation More than (ft) Additional Not Over (ft) Percent None 0 0 4 0 a 1 4 8 50 b 2 8 80 Using Table 204.13 -1, the Department will compute the volumes of material for payment under any sub -item based on the depths applicable to each zone between the foundation elevation as shown on the Plans and the final foundation elevation as approved by th e Engineer. For example: If the foundation were lowered 7 -1/2 feet below the foundation elevation shown on the Plans, the Department will compute the volume for the sub -item for a depth of 3 -1/2 feet and multiplied by the contract unit price for the class of material excavated plus 50%. The volume of material down to a level 4 feet below the foundation elevation shown on the Plans will be paid for at the contract unit price for the class of material excavated.
B.Cofferdams or Cribs If items for cofferdams or cribs have been provided for and installed for a designated pier or bent, the lump sum item is full compensation for the furnishing and installation of all material, maintenan ce, removal, and satisfactory clean up of the area , and for all tool s, equipment, labor , and incidentals necessary to complete the work. Concrete seal shall also be included, except when otherwise shown on the Plans, in which case, measurement and payment for concrete foundation seal will be as provided for under 604.30 and 604.31.
C.Foundation Preparation
1.Unless otherwise shown on the Plans, no direct payment will be made for Foundation Preparation and Backfill.
2.If Foundation Preparation is a separate pay item, t he lump sum price is full compensation for the preparation of fo undations for all substructures. The cost for cofferdams, shoring, pumping, or seal concrete required to establish the approved footing shall be 204.13 172 incidental to the lump sum bid for Foundation Preparation , except payment will be made at 40% of the price bid for the footing concrete when approved by the Engineer:
a.For leveling placed within the neat lines of the bottom of the footing, where permitted, and
b.For additional seal concrete require d by changes directed by the Engineer. Payment will be made only for the additional seal concrete placed within vertical planes located 18 inches horizontally outside of the neat lines of the bottom of the footing. No payment of seal concrete will be mad e for any depth the seal is embedded in sound material below the elevation of the bottom of the pier footing as shown on the Plans to allow placement of an adequate seal.
3.The Department will not allow a percentage increase for extra depth excavation req uired for the foundation preparation.
4.Unless otherwise provided, the Department will not pay for the sinking of test holes to test foundations.
D.Backfill Material (Flowable Fill) Payment for Excavatable Flowable Fill as backfill material for pipe will be included in the unit price paid for pipe unless otherwise shown on the Plans.
E.Backfill and Bedding Material Payment for granular backfill and concrete or aggregate bedding material will be included in the unit price paid for pipe unless otherwise shown on the Plans. The Department will not pay for: material moved before it has been measured by the Engineer; material specified to be moved under 203; slides or cave -ins occurring outside of the working limits specified in 204.08 and 204.10; material excavated outside of said working limits; material excavated, even though within the said working limits, below foundation elevation, as indicated or directed, and made necessary on account o f the construction methods of the Contractor, or its failure to provide sufficient or proper protection; presplitting of rock; material excavated below foundation when shooting; bulged material caused by driving piles in a foundation; water and 204.13 173 its removal ; and in general, material moved which would have been unnecessary to move to complete the structure in accordance with the Plans, these Specifications, or the directions of the Engineer. 205.01 174 SECTION 205 – EMBANKMENTS
205.01 Description ................................ ................................ ................... 174
205.02 Materials ................................ ................................ ...................... 174
205.03 Prepar ation of Embankment Areas ................................ .............. 174
205.04 Formation of Embankments ................................ ......................... 176
205.05 Stability of Embankments and Cut Slopes ................................ ... 179
205.06 Disposal of Excess or Unsuitable Material ................................ .. 180
205.07 Method of Measurement ................................ .............................. 180
205.08 Basis of Payment ................................ ................................ .......... 180
DESCRIPTION
205.01 Description
This work consists of constructing roadway embankments, including preparing the area upon which they are to be placed; constructing dikes within or outside the right -of-way; placing and compacting approved material wi thin roadway areas where unsuitable material has been removed; and placing and compacting embankment material in holes, pits, and other depressions within the roadway area. MATERIALS
205.02 Materials
For embankment and backfill, only use approved materi als, consisting of Road and Drainage Excavation, Channel Excavation, and Borrow Excavation material as specified in 203, or excess material as specified in 204. CONSTRUCTION REQUIREMENTS
205.03 Preparation of Embankment Areas
Before beginning embankment construction in any area, complete Clearing and Grubbing, Removal of Structures and Obstructions, and installation of preliminary erosion control measures according to the approved SWPPP as specified in 201, 202, and 209 respectively.
Source: Tennessee Standard Specifications for Road and Bridge Construction, 2021 Edition. Pages 162–182 of 1,072.