Wisconsin WisDOT Standard Specifications (within FDM) — Section 205

Effective with the December 2018 Letting 85 2019 Standard Speci fications Section 205 Roadway and Drainage Excavation

205.1Description

(1)This section describes excavating and disposing of material ta ken from within the right-of-way for

project construction.

(2)This section does not include ma terial obtained from borrow pi ts outside the right-of-way limits,

excavation for structures, or ot her excavation that separate bid items and specific measurement and payment are specified elsewhere in the specifications and contract.

205.2Materials

205.2.1 Classification

(1)The department classifies excavation as common, rock, stone pi les and stone fences, or marsh

excavation. If the contract contai ns the Excavation Common and Excavation Rock bid items, the engineer will classify that excavation as either common or rock , based on unfrozen material, as the contractor performs the work.

(2)The department classifies EBS out side of marshes as common or rock.

205.2.2 Common Excavation

(1)Under the Excavation Common bid item, excavate materials not c lassified as rock, stone piles and

stone fences, or marsh excavati on. For contracts without the Ex cavation Rock bid item, remove boulders having volumes of one c ubic yard or more under the Exc avation Common bid item. 205.2.3 Rock Excavation

(1)Under the Excavation Rock bid item, excavate hard, solid rock in ledges, bedded deposits, and

unstratified masses, and conglom erate deposits or any other material so firmly cemented they present the characteristics of solid rock, and the engineer determines it is impracticable to excavate this material without blasting or using rippers. Rock excavationals o includes removing rock boulders having a volume of one cubic yard or more.

(2)The classification of rock exca vation does not apply to crushe d aggregate or asphaltic base or surface

courses, or to concrete ba se or surface courses. 205.2.4 Stone Piles and Stone Fences

(1)Under the Excavation Stone Piles and Stone Fences bid item, re move and dispose of stones,

boulders, and rock fragments f ound assembled on the right-of-wa y in piles so that the engineer can make collective measurements by volume of the weight. If the contract includes a bid for this bid item, the classification applies to portions of the piles or assemble d stone masses found on the right-of-way that are removed and disposed of as specified. This applies reg ardless of whether this material occurs entirely above or partially below the ground surface. Do not cl assify stones in groups or piles of less than one cubic yard in volume under stone piles and stone fences. 205.2.5 Marsh Excavation

(1)Under the Excavation Marsh bid item, perform required excavation below the original ground level of

marshes and swamps underlying proposed embankments, within the limits indicated on the plans or as the engineer determines, and necessary or desirable to ensur e a stable foundation for embankment or to accelerate the subsidence of unstable material under embankment load. If old road embankment cores are encountered in areas involving marsh excav ation, salvage the portions of old road cores as designated on the pl ans and use them in the const ruction of embankments. This bid item also includes material of whatever nature encountered below the original ground elevations in areas designated for this work, exclusive of portions of old ro ad cores designated for salvage and used in construction of embankments.

(2)On contracts containing the Ex cavation Marsh bid item, excavate any marsh areas not indicated on

the plans but encountered during construction as marsh excavati on if the engineer orders removing these areas.

205.3Construction

205.3.1 General

(1)Excavate materials as the plans show or the engineer allows fr om within the right-of-way. Use

excavated material in the work to the extent practicable. Use e xcavated material with suitable engineering properties to constr uct the roadway, roadbed, emban kments, earth subgrade and shoulders, intersections, side ditches and dikes, channels, and waterways. Dispose of surplus or unsuitable material as specified in 205.3.12.

(2)Grade entrances, approaches, ditches, and channels beyond the right-of-way.

Effective with the December 2018 Letting 86 2019 Standard Speci fications (3) Replace unsuitable material with satisfactory material. Trim a nd finish the roadway. Maintain the work done under 205 in a finished condition until acceptance. 205.3.2 Preparing Roadway Foundation

(1)Remove vegetation taller than one foot before excavating or pl acing embankment. Remove heavy

sod, perishable material, unstable topsoil, muck, peat, and other undesirable material from the roadway foundation as defined in 101.3 . Also remove frozen material from the roadway foundation unless the engineer approves otherwise. Dispose of removed mate rial as specified in 205.3.12 unless the contract or the engineer directs otherwise.

(2)Salvage topsoil, as specified in 625.3.2 , from excavation areas and the roadway foundation. Remove

excess unstable topsoil from t he roadway foundation as EBS as s pecified in 205.3.4 .

(3)Compact, or prepare otherwise a s required, the existing ground within the roadway foundation as

necessary to support the embankmen t and attain the specified em bankment density.

(4)If placing embankment on side slopes 10 feet high or higher an d steeper than one vertical to 3

horizontal, provide vertically fa ced horizontal steps or benches in the slopes to support the embankment. The contractor may cu t or form the steps or benches while placing the embankment.

(5)Completely remove pavement, asp haltic surface, a nd rigid base from within the roadbed slopes and

underlying proposed embankments to a depth of 2 feet or more be low the finished grade line, or to the depth the plans show. 205.3.3 Drainage During Construction

(1)During construction, maintain roadway, ditches, and channels in a well-drained condition at all times

by keeping the excavation areas and embankments sloped to the a pproximate section of the ultimate earth grade. Perform blading or leveling operations when placin g embankments and during the process of excavation except if the excavation is in ledge rock or areas where leveling is impracticable or necessary. If it is necessary i n the prosecution of the work to interrupt existing surface drainage, sewers, or under drainage, provide temporary drainage until completing permanent drainage work.

(2)If storing salvaged topsoil on t he right-of-way during construction operations, stockpile it to preclude

interference with or obstruction of surface drainage.

(3)Seal subgrade surfaces as specified for subgrade intermediate consolidation and trimming in 207.3.9 .

(4)Preserve, protect, and maintain e xisting tile drains, sewers, and other subsurface drains, or parts

thereof, that the engineer judges should cont inue in service wi thout change. Repair, at no expense to the department, damage to these fa cilities resulting from negli gence or carelessness of the contractor’s operations. 205.3.4 Excavation Below Subgrade

(1)Remove deposits of frost-heave ma terial, unstable silty soils, wet and unstable soil, material salvaged

from old road cores in marshes, topsoil containing considerable humus or vegetable matter, rocks, or other undesirable foundation ma terial to the depth below finished grade as the plans show or the engineer directs. If possible, sl ope and drain the excavation bottoms to prevent water accumulation.

(2)Dispose of humus bearing soils and other excavated materials not suitable for embankment

construction as specified for disposal of surplus or unsuitable material in 205.3.12 .

(3)Use selected materials from r oadway and drainage excavation ha ving suitable engineering properties,

borrow, or granular backfill, as the plans or special provisions show or as the engineer directs, to backfill excavated areas. 205.3.5 Grading the Roadway, Intersections, and Entrances

(1)Use material with suitable engineering properties removed from excavation, to the extent practicable,

to construct the roadway. Use exc ess excavated material in othe r locations the plans show.

(2)Undercut or under fill to the nec essary depth, excavated slopes or areas and embankment slopes or

areas designated to receive topsoil or salvaged topsoil in order to provide for placement and finish of the specified quantity of topsoil or salvaged topsoil to the re quired grade lines and section.

(3)Perform excavation to avoid rem oving or loosening any material outside the required slopes. Replace

and thoroughly compact any material removed or loosened to the required cross-section.

(4)Grade intersecting roads, appr oaches, entrances, and driveways as the plans show or as the engineer

lays out. Construct intersections and private entrances, trims houlders and slopes, finish and blade the earth subgrade, and complete the ditches to the proper alignmen t, grade, and cross- section closely following the rough grading.

Effective with the December 2018 Letting 87 2019 Standard Speci fications 205.3.6 Constructing Ditches, Dikes, and Channels

(1)Construct inlets, outlets, swa mp, berm and intercepting ditches, dikes, or intercepting embankments

and channels where and as the plans show or where and as the engineer directs. Maintain inlets, outlets, swamp, berm, and intercepting ditches, dikes, or inter cepting embankments and channels to the required section until acc eptance. Perform the work in proper sequence with other work to provide adequate drainage and to minimiz e erosion and siltation.

(2)The department will include excavation from ditches and channe ls with the pertinent bid items

classified under roadway and drainage excavation.

(3)Use material with suitable engineering properties excavated from ditches and channels, to the extent

practicable, to construct the roadway and bac kfill abandoned di tches and channels. Dispose of unused excavated material as t he plans show or as the engineer directs.

(4)Do not deposit waste or surplus excavation within 3 feet of th e edge of ditches or channels or within a

greater distance as r equired to ensure st ability of the side sl opes. Spread waste or surplus material in thin, neatly shaped, uniform layers. Remove roots, stumps, logs , and other objectionable material in the slopes and bottoms of ditc hes and channels. Backfill the ho les with suitable material, or cut the holes to conform to the cross-section the plans show. If necessary, provide sufficient openings in spoil banks to allow surface drainage of adjacent lands.

(5)Provide suitable outlets or flumes from intercepting ditches t o roadway ditches where necessary as the

plans show. 205.3.7 Excavating Rock 205.3.7.1 General

(1)Remove rock, if encountered in excavation, to a depth of approximately 6 inches below the earth

subgrade between limits of the shoulder slopes. If the plans show design details covering the depth of rock excavation, perform the work according to the details. If the plans or special provisions do not require specific materials, then use selected material obtained from roadway and drainage excavation to backfill areas of EBS in roc k excavation. If excavation meth ods leave undrained po ckets in the rock surface, drain the depressions properly. If the engineer allows , the contractor may fill the depressions with engineer-approved impermeable material, at no expense to t he department.

(2)Excavate rock cuts using met hods and equipment so that the res ulting backslopes substantially

conform to the slopes the plans show or to the slopes established from the stakes set for excavation. Avoid creating depressions in or substantial displacement of ma terial outside the lines, limits, or slope planes defined by the stakes. Scale the backslopes in rock cuts to dislodge loose rock. Dispose of removed material in the manner specified for other excavation.

(3)Undercut the slopes of rock cuts if designated to receive tops oil, or salvaged topsoil to the depth

necessary to allow placing the specified quantity of topsoil or salvaged topsoil, and finish to the required section. 205.3.7.2 Presplitting Rock

(1)If the plans show or t he engineer autho rizes, employ the presp litting technique to split the face of the

rock cut in a relatively smoot h plane along the designated back slope, before removing the interior portion of the cut by blasting.

(2)Remove soil and loose or decompo sed rock overlying the surface of the rock to be split to the

elevation the engineer designates or approves before drilling the presplitting holes.

(3)At the beginning of the presplitting operation or if encountering material of different geologic

characteristics, dr ill, blast, and excavate short test sections, up to 100 feet in length, to determine the optimum spacing, size, and loading of the holes. Do not perform testing until the engineer approves a contractor-prepared plan of the te st section. After presplittin g the test section, ex pose the presplit face to allow the engineer to exami ne and evaluate the results. If t he results are unsatisfactory, make adjustments in hole size and spacing, size and spacing of charges, and other aspects of the plan to produce an acceptable split face.

(4)Drill holes not larger than 3 1/2 inches in diameter at a spacing determined from the test section, but

not less than 24 inches and not more than 42 inches.

(5)Drill holes on the required sl ope line and at the required slo pe inclination to the full depth of the cut or

to a predetermined stage elevation. If the depth of cut is grea ter than is practicable to maintain the required alignment of the drilled holes, drill, blast, and exca vate the cut in 2 or more lifts. If the cut is too deep for presplitting to the full-required depth in one operation, the engineer will allow a maximum offset of 12 inches at the bottom of each lift for use in drilling the next lower presplitting pattern. Plan

Effective with the December 2018 Letting 88 2019 Standard Speci fications the offset benches so the toe o f the completed rock slope coinc ides with the toe of slope the plans show.

(6)Carefully charge drill holes for presplitting with manufacture d cartridge-type explosives, fully stem each

hole, and detonate the charges simultaneously.

(7)Before blasting the interior portion of the excavation area, p resplit rock slopes, e ither by separate

operations or by time delay fuses that fracture the slope line before the charges det onate in the interior portion.

(8)Position drill holes for production blasting to avoid damage t o the presplit face. Do not place the

bottom of the production holes below the bottom of the presplit holes. Do not drill portions of production drill holes within 4 feet of a presplit plane except as the engineer approves.

(9)Use explosive charges, detonating cord, spacing, and other ite ms necessary for the blasting operation

conforming to the explosive manuf acturer’s recommendations and instructions. 205.3.8 Marsh Excavation and Disposal

(1)If encountering muck or peat mar shes, complete excavation of t he marshes as soon as practicable to

obtain maximum settlement before proposed base and surface cons truction.

(2)Begin excavation of wet marshes with relatively unstable side slopes at one end and proceed in one

direction to the full width acro ss the entire marsh immediately ahead of backfilling. Ensure the method and sequence of excavating and backfilling result in the comple te removal or displacement of peat or muck from within lateral limits the plans show or as the engineer staked, and to the bottom of the marsh or to firm support. Excavate displace d peat or muck accum ulating ahead of the advancing embankment toe. Construct embankme nts as specified for placing in marsh in 207.3.3.

(3)Completely excavate, to the ext ent practicable, dry marshes ha ving relatively stable side slopes and

firm bottoms to the width the plans show or as the engineer sta ked, and to the bottom of the marsh. Backfill the area in layers as spe cified for placing layers in 207.3.2.

(4)Unless the contract specifies o therwise, the contractor may te mporarily deposit the excavated material

outside the toe of the slope of t he proposed embankment but not over marsh or wetlands. After completing the embankment, place t he excavated material against the fill slopes, and spread the material between the fill and marsh ditch if not placing over m arsh or wetlands. Dispose of left over material as unsuitable material , or use it as the plans show. I f disposing of excavated material by hauling to other locations, compl ete hauling before construction of any subbase, base, or surface course. 205.3.9 Removing Embankment Surcharge

(1)Remove and dispose of excess f ill placed above the elevation for earth grade over deposits of

unstable material to secure displacement or settlement. Remove surcharge only after the engineer determines the fill has reached stability or the required settl ement. 205.3.10 Removing Masonry Walls, Foundations of Buildings, or Other Structures

(1)Unless the plans show otherwise , remove masonry walls or found ations of buildings or other

structures as follows:

1.Within the road bed, to a depth at leas t 2 feet below the su bgrade.

2.Outside the roadbed, to a d epth at least 2 feet below the f inished grade.

3.At any location, to the ext ent required to avo id interferin g with the work.

(2)Break holes in basement floors to allow drainage. Backfill those portions of bas ements or other

openings resulting from removing buildings or other structures, or openings resulting from removing walls or foundations of buildings or structures, lying within t he shoulder lines of the new roadway, subgrade elevation with suitable material from roadway excavati on, unless the contract specifies granular backfill. Backfill similar openingsly ing outside the ditch lines of the new roadway with material secured from roadway excavation. 205.3.11 Incorporating or Disposing of Stones, Broken Rock, and Boulders

(1)Incorporate stones, broken ro ck, and boulders not required for other construction included in the

contract, to the extent practicable, in embankments outside the limits of any propo sed structure or structure piling. Completely f ill the voids between them withs atisfactory soil. Dispose of material not incorporated in the work at no expense to the department, either by burying in the ground within the right-of-way in an engineer-appro ved manner or by placing off the right-of-way and out of sight from a public highway. If placing material outside the right-of-way, c omply with all regulations relating to disposal of solid waste. Obtain written permits for disposal fr om the owner of the property where

Effective with the December 2018 Letting 89 2019 Standard Speci fications placing the material, unless disposing of the material at a lic ensed waste disposal operation. Furnish permits, or copies of permits, to the engineer before disposal. Do not deposit waste in wetlands. 205.3.12 Incorporating or Disposing of Surplus or Unsuitable Material

(1)Dispose of vegetation as specif ied for clearing and grubbing u nder 201.3 . Save material containing

humus or of a nature suitable to support vegetation but unsatis factory for constructing embankments. Use this material in salvaged t opsoil operations. The contractor may, if the engineer approves, use surplus humus-bearing soils, and other excavated materials not suitable for embankment construction but suitable to uniformly widen embankments, to flatten slopes, and to fill low places in the right-of-way for these purposes, unless specified otherwise.

(2)Do not deposit excavated material along the roadsides above th e elevation of the adjacent roadbed,

unless the plans show or the engineer allows.

(3)Dispose of surplus excavation that is not, or cannot be, dispo sed of by flattening slopes or filling in low

places on the right-of-way, a t no expense to the department. Lo cate disposal sites outside the right-of- way, and comply with all regulations relating to disposal of so lid waste. Ensure that disposal sites are neatly constructed. In performing these operations, do not crea te a nuisance or cause pollution or siltation of natural watercourses, streams, lakes, wetlands, or reservoirs. Furnish w ritten permits to the engineer as required from the owner of the property under 205.3.11 before disposal. Do not deposit waste in wetlands. 205.3.13 Approving Cuts and Shallow Fills

(1)The department may approve areas of subgrade in cuts and shall ow fills for subseque nt operations.

The department defines shallow f ills as areas requiring 2 feet or less of fill material. The contractor is responsible for the subgrade in the embankment.

(2)After rough grading, on all or a portion of the subgrade in cuts and shallow fills, identify yielding areas

for engineer evaluation as follows: - When the grade is ready for placing subgrade improvement mate rial. - When the subgrade is compl ete and ready for blue tops.

(3)The engineer will evaluate cuts a nd shallow fills to determine if corrective work or EBS is required. If

the engineer requests, provide loaded trucks and run the grade as the engineer directs to confirm yielding areas. Perform EBS in yielding areas and backfill as t he engineer directs.

(4)If satisfied that a cut or shallow fill area requires no EBS, the engineer will approve that area for

subsequent operations. 205.3.14 Finish Grading

(1)Complete the grading, trimming, and finishing before constructing the subbase, base, or surface

courses.

(2)Make gradual adjustment in slopes to avoid injury to standing trees or to harmonize with existing

landscape features, especially at the intersection of cuts and fills.

(3)Round the crests of earth cut banks as the plans show or as the engineer directs.

(4)Merge constructed earth slopes with adjacent terrain and subst antially conform to the plan cross-

sections. Use blading or other operations, to partially smooth the horizontal serrated condition of slopes ordinarily left by excavating equipment. Produce slopes that are slightly rough and irregular and have a general contour of the required slope.

(5)Flatten, round, or modify the slopes and banks of existing ditches, channels, berms , and dikes within

the clear zone to the extent nec essary to remove obstacles or o bstructions encountered by vehicles leaving the adjacent traveled way.

(6)During grading operations and pending acceptance of grading or placement of subbase, base, or

surface course, provide continuous maintenance of the entire ro adbed and perform blading and repair work necessary to keep the grade smooth and to the required gra de and cross-section specified. The contractor is not required to maintain or restore the minimum r equired density in the graded roadway after completing shaping, trimming, and finishing operations, e xcept as specified for preparing the foundation in 211 before placing subbase or base under the contract.

(7)Refill and compact washouts caused by erosion.

205.3.15 Preserving Trees and Shrubs

(1)Protect trees and shrubs designated for preservation from scar ring or other injury during grading

operations.

Effective with the December 2018 Letting 90 2019 Standard Speci fications (2) If excavating around trees to be preserved, do not disturb the original ground around the trees within a minimum distance of one foot or twice the diameter of the tree, whichever is the greater distance. Cleanly cut exposed roots resulting from excavation, and cover them with humus-bearing soil.

(3)If the plans, special provisions, or the engineer requires, co nstruct tree wells to pro tect trees or shrubs

surrounded by excavation or embankment. 205.3.16 Dust Control

(1)Minimize dust dispersion from the subgrade during grading and maintenance operations, until the work

is accepted, by applying water or other engineer-approved dust control materials as the contract specifies or the engineer requires.

205.4Measurement

205.4.1 Excavation

(1)The department will measure all cl asses of roadway and drainag e excavation by the cubic yard

acceptably completed as computed using the method of average en d areas, with no correction for curvature, except as follows:

1.The engineer and contractor m utually agree to an alternate volume calculation method.

2.The method of average end areas is not feasible.

3.Other methods are specif ied here in 205.4.1.

(2)For minor quantities, the engineer may elect to measure Excavation Common by the cubic yard in the

vehicle. The engineer will determine the capacity of each haul vehicle to the nearest 0.1 cubic yard.

(3)The department will measure Exca vation Rock in ledges and soli d masses by the cubic yard

acceptably completed. The department will perform this measurement by making vertical measurements for determining end areas within the limits of the roadbed as defined by the shoulder slopes. These vertical measurem ents will extend from the surface of the rock to an elevation 6 inches below the subgrade or ground surface, or to the depth indicated on the plans, or to the bottom of the solid ledge or mass if the rock does not extend downward to the elevation specified, or indicated below the established grade.

(4)The department will measure boulders and surface stone with a volume of one cubic yard or more

individually and compute the volume from average dimensions tak en in 3 directions, except as specified below for Excavation Stone Piles and Stone Fences.

(5)If the contract includes a separate bid item for Excavation Stone Piles and Stone Fences, the

department will measure the stone piles or portions of stone pi les removed in cubic yards in their original position, computed by the method of average end areas, with no correction for curvature, or, if the engineer elects, by the method of truncated prisms. Measurement under Excavation Stone Piles and Stone Fences includes stones , regardless of size; located i n the stone piles and stone fences, and the department will make no classification of stone size for material measured un der this bid item.

(6)If undercutting designated slopes to provide for placing topso il or salvaged topsoil, the undercut is

incidental to the Topsoil or S alvaged Topsoil bid items.

(7)The department will measure Excavation Marsh in its original position, by the average end area

method, within the limits of excavation. The department will us e this method if the contractor excavated and formed a reasonably well defined trench of required cross-section, with relatively stable side slopes, and a bottom that is the bottom of the marsh or a satisfactory suppor t for the backfill and embankment. In cases that the exca vation does not result in a r easonably well defined measurable trench with relatively stable side slopes, the department will measure the cross-se ction area based on the lateral limits of the excavation shown in the plan cross-se ctions or as staked in the field. The department will determine the depth between the original marsh surface and the bottom of the placed fill by taking soundings during the marsh excavation or by taki ng borings through the completed fill. The department will not measure marsh material from outside the lateral limits defined above that is excavated or is displaced by the fill.

(8)If it is not possible to compute volumes of the various classes of roadway and drainage excavation by

the method of average end areas du e to erratic location of isolated deposits, the department may compute the volumes by alternate methods involving 3-dimensional measurements.

(9)The department will not measure for payment materials excavate d in forming benches or steps in

preparing the foundation for embankments placed on slopes.

(10)The department will not measure ex cavated material used for pu rposes the contract does not

designate, except as specified for use of materials found on the project in 104.8 . The department will not measure material excavated beyond the limits of the require d slopes unless the engineer allows

Effective with the December 2018 Letting 91 2019 Standard Speci fications overbreak in rock cuts and that o verbreak was beyond the contra ctor’s control. In this case the department may measure this overbreak.

(11)The department will measure erosion control, fertilizing, and seeding for material disposal sites as

specified for material disposal sites in 628.4.1.1 . 205.4.2 Presplitting Rock

(1)The department will measure Presplitting Rock by the linear fo ot of drill holes, inc luding test section

holes, drilled along the face of acceptable presplit rock slopes. The department will take the measurement from the top of the drill hole at the rock surface to the elevation of the roadway ditch, to a predetermined bench elevation or to the bottom of the rockle dge or mass where the rock does not extend to the roadway ditch or predetermined bench elevation. T he department will not include overbreak quantities in the meas urement of Excavation Rock wher e presplitting is used.

205.5Payment

205.5.1 General

(1)The department will pay for measured quantities at the contrac t unit price under the following bid

items: ITEM NUMBER DESCRIPTION UNIT

205.0100 Excavation Common CY

205.0200 Excavation Rock CY

205.0300 Excavation Stone Piles and Stone Fences CY

205.0400 Excavation Marsh CY

205.1300 Presplitting Rock LF

205.5.2 Excavation

(1)Payment for the Excavation bid items under this section is full compensation for all work specified for

those excavation classes under 205 for which no separate unit prices are included in the contract, except as specified otherwise in 203 and 204 for removing concrete structures, and below for performing EBS after the engineer approves the subgrade in cut areas. The cost of removing walls, foundations, etc., the satisfactory disposal of resulting mater ial, and the backfilling of basements or openings resulting from removing walls, foundations, etc., for which no separate unit prices are included in the contract, is incl uded in the contract unit pric e for the Excavation bid items, except for removing concrete str uctures. The departm ent will not pay extra for this work, except the department will pay separately for providi ng the required gr anular backfil l under the Backfill Granular bid items, and, except as specified above for removing concrete structures and EBS performed after the engineer approves the subgrade in cut areas. Payment also inclu des hauling.

(2)The department will only pay for engineer-approved EBS to corr ect problems beyond the contractor's

control. Work performed under 105.3 to correct unacceptable work is the contra ctor's responsibilit y. For EBS work performed where the engineer did not approve the s ubgrade for subsequent operations, the department will pay for EBS a t the contract price under the pertinent excavation and backfill bid items, or absent those bid items as extra work. For EBS work pe rformed where the engineer approved the underlying layers for subs equent operations, the department will pay for EBS as follows:

1.Up to a maximum of $25,000 per contract, the department wil l pay as follows:

1.1For excavation: 3 times the contract unit price for the Ex cavation Common bid item under the EBS

Post Grading administrative item.

1.2For backfill with the materials the engineer directs: at the contract unit price fo r the bid items of

each material used to fill the excavation.

1.3For excavation or backfill without contract bid items: as extra work.

2.After exceeding $25,000 pe r contract, the department will p ay for additional EBS in engineer-approved

areas as determined under 109.4 .

(3)If the contract does not include the Excavation Rock bid item, the department will pay 5 times the

contract bid price of the Excavation Common bid item to remove boulders having volumes of one cubic yard or more. The department will pay for these boulder removals under the Removing Large Boulders administrative item.

(4)Constructing and removing temporary drainage installations as specified under 205.3.3 is incidental to

the work under this section.

(5)The department will pay for erosion control, fe rtilizing, and seeding of material disposal sites as

specified for material disposal sites in 628.5.1 .

Effective with the December 2018 Letting 92 2019 Standard Speci fications (6) The department will pay for refilli ng and compacti ng washouts caused by erosion under the contract bid item for the additional volume of material used, or as extr a work according to 107.14 , except that if the erosion is caused by the c ontractor’s negligence then the c ontractor performs refilling and compaction at no expense to the department. 205.5.3 Presplitting Rock

(1)Payment for Presplitting Rock i s full compensation for drilling, charging, stemming, and blasting; and

for providing materials, including explosives.

Effective with the December 2018 Letting 93 2019 Standard Speci fications Section 206 Excavation for Structures

206.1Description

(1)This section describes excavati ng for culverts, structural pla te pipe, and structural plate pipe arches,

bridges, and retaining walls. It a lso describes removing old su bstructure units within the space occupied by the ne w structure.

206.2Materials

(1)Furnish backfill material of a quality acceptable to the engin eer and free from froz en lumps, wood, or

other extraneous or perishable ma terial. The contractor may use engineer-approved material obtained from excavation.

(2)If the contract specifies struc ture backfill, furnish material conforming to 210. The contractor may use

material conforming to the requi rements for structure backfill obtained from excavation as specified under 104.8 .

206.3Construction

206.3.1 General

(1)Under the Excavation for Structures bid items, excavate material of whatever nature encountered. The

department will not classify this e xcavation as common, rock, o r marsh excavation under 205 or as dry or wet excavation.

(2)Remove logs, stumps, and other m aterials and obstructions nece ssary to place the foundations and

structure. Dispose of material obtained from excavation. Backfi ll, compact, shape, slope, and clean the site.

(3)Construct, and subsequently remov e, necessary cofferdams and c ribs or well-point systems, and the

necessary sheeting, shoring, bracing, draining, and pumping to allow constructing the substructure, above the seal, in the dry. Do no t use stream diversions and ea rth dikes instead of specified cofferdams or well-point systems, unless the engineer authorizes in writing. 206.3.2 Excavation Depth

(1)The elevation of the bottoms of footings, as the plans show, i s approximate only. The engineer may

order, in writing, changes in dimensions or elevation of footin gs necessary to secure a satisfactory foundation. 206.3.3 Cofferdams and Cribs

(1)If providing cofferdams and cribs for foundation construction, ensure that they are safely designed and

constructed, carried to adequate depths and heights, and are ma de watertight as necessary for the proper performance of the work. C onstruct cofferdams and cribs so that interior dimensions give sufficient clearance for the cons truction of forms and the insp ection of their exteriors, and to allow pumping from sumps outside the forms. If cofferdams or cribs ti lt or move laterally during the process of sinking, right, reset, or enla rge them to provide the necessary clearance. The contractor is responsible for any claims for damages resulting from the use o f a well-point system. 206.3.4 Protecting Concrete

(1)Construct cofferdams and cribs to protect fresh concrete again st damage from a sudden rising of the

stream and to prevent damage to the foundation by erosion. Plac e wales and cross braces at locations that allow construction of the su bstructure unit without constr uction joints other than those the plans show. If required to leave wales or braces in place, use only p ipe, precast concrete or rolled steel sections. Do not box out with timber braces. 206.3.5 Plans Required

(1)If the engineer requests, submi t one copy of signed and sealed plans as specified for cofferdams and

cribs under 105.2 , showing the proposed method of cofferdam or crib construction for the file. At the engineer’s request, submit 2 additional copies of these plans f or review. If the engineer does not find the plans submitted for reviews atisfactory, make the required changes. Whether or not the engineer requests submittal of the plans or concurs in the use of the pl ans as submitted or corrected, the department will not relieve the contractor of the responsibility to secure a safe and satisfactory cofferdam or crib. 206.3.6 Removal

(1)Unless specified otherwise, remov e cofferdams or cribs, including sheeting and bracing, after the

completion and curing of the subs tructure unit. Exercise care n ot to disturb or otherwise injure the finished masonry.

Source: Wisconsin Standard Specifications for Highway and Structure Construction, 2019 Edition. Pages 94–101 of 601.

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204 Removing or Abandoning Miscellaneous Structures

206 Excavation for Structures