214STRUCTURE EXCAVATION AND BACKFILL FOR DRAINAGE AND MINOR STRUCTURES

128

214.04Method of Measurement

The quantity of excavation will be the number of cubic yards {cubic meters}, measured in its original position, that is excavated in accordance with the details shown on the plans and the following limitations.

For masonry structures other than culverts, measurement will be made of material removed from the area bounded by vertical planes 1 foot {300 mm} outside of the neat lines of the foundation or footing plan and parallel thereto, and to the elevations shown on the plans or directed by the Engineer to provide installation on a suitable foundation. No measurement or payment will be made for material excavated outside these limits.

For box, arch, and pipe culverts with wing walls or headwalls or other minor structures including storm sewers, measurement will be made of the material removed in accordance with the following: The excavation shall be considered to be a trench with vertical sidewalls. No separate measurement for minor structures (inlets, junction boxes, catch basins, manholes, etc.) other than noted below, such being considered incidental to work. The length of the excavation shall be the actual length of the structure (including inlets, junction boxes, etc.) measured along the flowline plus 1 foot {300 mm} at each end. When headwalls or wing walls are used, the length shall be the average net length of the structure, tip to tip of wings. The width of the excavation shall, in the case of pipe structures, be considered the inside diameter of the pipe plus 3 feet {1 m}. For box culverts, the width shall be the outside width of the barrels plus 4 feet {1.2 m}. On all culvert structures, no allowance will be made for wing flares or toe walls.

The depth of excavation will be as deep as required to install the structure on a suitable foundation to the flowline indicated. This depth shall then be measured in accordance with the following:

at least 1 foot {300 mm} above the elevation of the top of the pipe. The depth of excavation shall be measured from a point 1 foot {300 mm} above the top of the pipe, or from subgrade elevation in cut sections.

of the original ground will be taken at major breaks in the ground line profile and at changes in the culvert barrel widths along the length of the culvert as defined in Item 2 above.

The average end area method shall be used in computing the volume and no measurement for payment will be made for material excavated outside of the limits noted above.

No measurement or payment will be made for excavation for side drainpipes of any size or for side drain culverts unless so provided by plan details. The cost of such excavation shall be included in the price bid for the items; however, pipe designated on the plans as storm sewer pipe will not be classified as side drain.

Foundation backfill will not be measured directly but the volume will be fixed at 150 percent of the volume of the excavation which it replaces that lies between the bottom of the structure and the bottom elevation of the trench ordered excavated. Where satisfactory structure foundation is provided by the normal process of removing and backfilling unsuitable material under fill areas, none of such backfill will be classified as foundation backfill. EXCAVATION FOR BRIDGES 129

214.05Basis of Payment

Payment will be made for the number of cubic yards {cubic meters}, measured as detailed above, at the contract unit price bid for Structure Excavation. Such payment shall be payment in full for furnishing all materials, equipment, tools, labor, pumping, bailing, draining, and all incidentals necessary to complete the work and shall include installation and removal of any cribs, cofferdams, shoring, sheeting, or other protection, the satisfactory disposal of any unsuitable material from the excavation, and the placement and compaction in backfill or embankment of the material excavated and suitable for such use.

Payment for the calculated cubic yards {cubic meters} of this material, determined as noted herein, will be made at the contract unit price bid which shall be full compensation of the item complete in place and includes furnishing of all material, placement, compaction and all equipment, tools, labor, and incidentals necessary to complete the work.

214-A Structure Excavation - per cubic yard {cubic meter} 214-B Foundation Backfill, Local/Commercial - per cubic yard {cubic meter} EXCAVATION FOR BRIDGES

215.01Description

The work under this Section shall cover foundation excavation for bridge structures which includes the removal of all material necessary for the construction of foundations and substructures, including backfill, all in accordance with the plans or as directed by the Engineer. It shall, unless otherwise stipulated by the plans or proposal, include the furnishing of all necessary equipment and the construction of all sheeting and shoring, cribs, cofferdams, caissons, dewatering, etc., which may be necessary for the execution of the work. It shall also include the subsequent removal of these items and the placement of all necessary backfill as hereinafter specified. It shall also include the disposing of excavated material, not required for backfill, in a manner and in locations as approved by the Engineer. The item of Cofferdam and Pumping, when specified on the plans, shall not be covered under this Section. Attention is directed to Section 503 for the requirements of this item.

215.02Classification of Material

Excavation for bridges shall include all material removed except water or other liquids. Excavation of material for bridges not within the classification of roadway or drainage excavation will be Unclassified Bridge Excavation.

215.03Construction Requirements

The Contractor shall notify the Engineer a sufficient time in advance of the beginning of the excavation for each structure, so that elevation and measurements may be taken of the existing ground. No payment will be made for material removed or excavated before these measurements have been taken.

Ample opportunity shall be given to the Engineer for the inspection of foundation pits and the measurement of material removed. In no case shall a foundation be closed to view until it has been inspected and approved.

When in the Contractor's opinion, rock, or other firm foundation material of equal bearing value is encountered at an elevation above that shown for the footing, and at a location not subject to erosion or scour, the Contractor shall notify the Engineer in order that he may investigate and determine if it is advisable to raise the bottom of the footing. EXCAVATION FOR BRIDGES 130

When the excavation for a footing has been completed to the approximate elevation shown on the plans without encountering satisfactory foundation material, the Contractor shall notify the Engineer in order that he may make an inspection and investigation, such investigation to consist of drilling, probing or jetting by the Contractor, a maximum of 4 holes per footing, each hole a maximum depth of 20 feet {6 m}. No direct payment will be made for this operation. If additional holes are required, they will be paid for as provided in Article 104.03. The Engineer will then fix the proper elevation of the footing or decide upon its treatment.

When apparently satisfactory foundation material has been reached, the Contractor shall drill or probe not more than 4 exploratory holes to a maximum depth of 10 feet {3 m}. The drilling will not be required if a note is shown on the plans to waive this requirement. No direct payment will be made for this operation. If additional holes are required, they will be paid for as provided in Article 104.03.

The excavation for the bottom of the footing shall be carried to the depth as shown on the plans or as designated. The design and elevation of footings are based on soundings taken at certain points for design purposes only. These soundings may or may not be representative of the actual conditions encountered during construction. Bidders must assume the risk of having to excavate to a greater or lesser depth without altering the contract unit prices in the proposal, except as hereinafter set forth, and the footing elevations shown on the plans shall be considered as approximate only. The Engineer may order in writing such changes in dimensions or elevations of footings as may be necessary to secure satisfactory foundations for the structure. The size of the excavation shall in all cases be ample to accommodate necessary forms down to rock, marl, Selma chalk or similar hard material suitable for embedment of footings; excavation in such materials shall be as near as possible to the neat lines of the footings and the footings poured without the use of forms. In hard materials which cannot be cut to neat lines with a pneumatic spade, line drilling along the neat lines not to exceed 9 inch {230 mm} centers will be required. In dry soils, suitable for footing embedment, capable of providing stable, neat footing lines, permission may be given to allow pouring of footings without the use of forms; otherwise, the excavation shall be sufficient for forming the foundations. The horizontal limits of excavation shall not extend beyond what is required for sheeting, bracing, forms and reinforcing cages.

Cofferdams or sheeting and shoring will be required in foundation excavation work when work is adjacent to pavement, sidewalks, railroad tracks, utilities, etc., when the material encountered is unstable, when such excavation will present a hazardous or undesirable condition, or when necessitated due to water conditions. Materials and design to be used for this work will be determined by the Contractor. Working drawings and design calculations will only be required if the foundation work is within an area adjacent to the track line. These areas are where a railroad company will require adequately designed cofferdams, sheeting and shoring to protect the stability of the track line during construction. The Contractor shall contact the railroad company to obtain the design requirements for the cofferdams, sheeting and shoring. Working drawings and design calculations for cofferdams, sheeting and shoring shall be submitted in accordance with the requirements given in Article 105.02. If a seal is required in a cofferdam covered under this Section, it shall meet all of the requirements and be measured for payment in accordance with Section 503.

All material used for backfill shall be soil of an acceptable quality. All spaces excavated and not occupied by abutments, piers or other permanent work shall be backfilled. Backfill around all units of a structure shall be completed as soon as practical after the unit has obtained the required strength. Bracing, forms and rubbish shall be removed from the excavated area before backfilling is commenced. Backfill within the limits of the roadway shall be as required by Section 210; all other backfill, except that placed below water level, shall be tamped and compacted as required by the Engineer. EXCAVATION FOR BRIDGES 131

If the surface upon which the footing is to be placed becomes soft or muddy and will not dry out after the excavation has been dewatered, the Engineer may direct that a foundation course of approved free draining commercial material, as specified in Subarticle 214.02(b), be used under the footing. If this soft and muddy condition occurred through no fault or negligence of the Contractor, the Engineer, at his discretion, may order payment to be paid under Item No. 214-B, Foundation Backfill, Commercial. If this Item is not in the contract, then payment will be made as Extra Work as specified in Article 104.03 and Article 109.04. When the above condition was the result, in the opinion of the Engineer, of negligence on the part of the Contractor, no payment will be made for the required foundation backfill. Compaction shall be as directed by the Engineer.

The natural ground adjacent to the structure shall not be disturbed without permission of the Engineer. Unless otherwise specified, no excavation shall be made outside of caissons, cribs, cofferdams, steel piling or sheeting. The natural stream bed adjacent to the structure shall not be disturbed without permission from the Engineer. If any excavation or dredging is permitted at the site of the structure before caissons, cribs or cofferdams, or piling are placed, the Contractor shall, without extra compensation and after the foundation is in place, backfill all such excavations to the original or established ground surface or stream bed with satisfactory material. No material or debris shall be deposited in any designated navigation channel during construction except with the approval of the Engineer. Such material or debris shall be removed to the normal navigation channel depth prior to completion and acceptance of the contract. Any material or debris resulting from the Contractor's operations deposited outside any designated navigation channel or other streams during construction except such fill as may be ordered as a permanent part of the work shall be removed and the channel freed from all obstructions before completion of the work.

Surplus excavated material, after piers and abutments are backfilled, shall be used to obliterate construction scars at or near the bridge site, to smooth out depressions in and near the stream banks or as otherwise directed by the Engineer.

215.04Method of Measurement

When listed as a pay item in the contract, the quantity of Unclassified Bridge Excavation will be the number of cubic yards {meters} of material excavated, measured and calculated in its original position, subject to the following limitations:

however, no measurement will be made for material removed outside of the area bounded by vertical planes 1 foot {300 mm} outside of the footing and parallel thereto down to hard material described in Subarticle 215.03(b) or for material excavated outside neat lines of footings in such hard material. For stepped footings the volume will be measured and computed separately for each step. When the size of a footing is reduced after the Contractor excavated for a larger footing as directed, the excavation will be measured based on the larger footing.

direct payment will be made for their removal.

encasements.

of abutment caps on drilled shaft foundations.

the bottom of the footing, unless the removal of said material is ordered. Excavation necessary and incidental to the cleaning or excavating of crevices in the floor of a foundation pit below the established footing elevation will not be measured for payment.

removal of material that flows through or over cofferdams or caissons.

from the following: EXCAVATION FOR BRIDGES 132

o L = Length of footing shown on contract plans (feet {meters}); o W = Width of footing shown on contract plans (feet {meters}); o D = Final approved elevation of the bottom of the footing (feet {meters}); o B = Average elevation of the mud line or groundline (river bottom) at the cofferdam (feet {meters}); o Ve = Volume of excavation for which payment will be made (cubic yards {cubic meters}). o Ve = L x W x ( B - D ) / 27 {Ve = L x W x ( B - D )}

a seal concrete footing, depending on the details of construction selected by the contractor. No direct payment will be made for any excavation outside of the footing plan dimensions shown on the contract plans.

Each accepted Cofferdams or Sheeting and Shoring unit will be measured for payment as a lump sum unit. A unit shall consist of all piers, bents, and abutments on a specific bridge which are not designated by the plans for Item 503-B, Cofferdam and Pumping. Partial payments will be allowed on monthly estimates in accordance with Subarticle 215.05(a)2.

215.05Basis of Payment

Payment for the yardage of Unclassified Bridge Excavation as provided above shall be payment in full for the furnishing of all materials, equipment, tools, labor, pumping, bailing, drainage, sealing crevices, backfilling (including foundation backfill), compacting, disposal of excavated material, and for all incidentals necessary to complete the work in accordance with the plans and these specifications. If a footing is lowered below the elevation shown on the plans, adjustments in the unit price for all of the Unclassified Bridge Excavation of the footing involved will be made as follows: Depth Lowered Below Plan Elevation Bid Price Plus 0 to 3 feet {1 m} 0% Over 3 feet {1 m} to 6 feet {2 m} 50% Over 6 feet {2 m} to 10 feet {3 m} 75% Over 10 feet {3 m} 100% For stepped footings, the above adjustments will be computed separately for each step.

Payment for a lump sum unit of Cofferdams or Sheeting and Shoring as provided above shall be payment in full for the furnishing of all materials, equipment, tools, and labor necessary to complete the construction of the specified piers, bents, and abutments and the removal and disposal of any cofferdams or other temporary construction used in the prosecution of the work. Payment for each accepted Cofferdams or Sheeting and Shoring unit will be made at the contract lump sum price bid for each unit, complete in place. Partial payments will be made on monthly estimates based on the percentage of the total work performed on each unit as estimated by the Engineer. In making this estimate each pier or bent considered as part of a unit will be given an equal percentage of the total unit. Upon completion of the foundation above ground line at a particular pier or bent, that percentage of the total unit may be paid. No consideration will be given for additional compensation for this item when footing elevations are lowered less than 10 feet {3 m}, such being considered incidental to the work. If elevations are lowered 10 feet {3 m} or more, consideration will be given for additional costs caused by the revised elevations in accordance with Article 109.04.

215-A Unclassified Bridge Excavation - per cubic yard { cubic meter} 215-B Cofferdams or Sheeting and Shoring, * , ** - per lump sum * Station Number, Bridge Number, Ramp Number, etc. ** Lane, if applicable.