2106Excavation and Embankment – Compacted Volume Method

2106.1DESCRIPTION

This Work consists of excavating, placing, compacting, testing, finishing, and disposing of embankment Materials. Materials are classified as either excavation or embankment Materials. No shrinkage or swell factors have been applied or will be applied to any Excavation or Embankment items.

2106.2MATERIALS

A Excavation A.1 Excavation – Common Material not classified in any other category. Excavation-common includes topsoil excavation. A.2 Excavation – Subgrade Material in the Road Core below the Grading Grade exclusive of Excavation – rock, Excavation – muck, Excavation – channel and pond, Excavation – rock channel. A.3 Excavation – Rock Material that requires drilling, blasting, or ripping before excavation. This includes boulders and other detached rock larger than 1 cubic yard. A.4 Excavation – Muck Organic Soils and other unstable soils, and below the natural ground level of marshes, swamps, or bogs, regardless of the moisture content. Muck excavation is limited to areas over which the Roadway embankment or a Structure is to be constructed. A.5 Excavation – Channel and Pond Material from channel changes, waterways, and ponds outside of the Roadway embankment not classified as rock channel excavation. A.6 Excavation – Rock Channel Material classified as rock excavation from channel changes and waterways outside of the Roadway embankment. B Embankment B.1 Common Embankment Select Grading Material, mineral soils found in the Triaxial Chart in the Grading and Base Manual, excluding Silt. Organic Soils and Marl are also excluded. Select Grading Material may contain up to 100 percent recycled Materials composed of recycled concrete (maximum of 75 percent), and recycled asphalt. B.2 Granular Embankment ....................................................................................... 3149.2B Table 3149.2-1, Granular Material B.3 Select Granular Embankment ............................................................................ 3149.2B Table 3149.2-1, Select Granular Material B.4 Select Granular Embankment Super Sand .......................................................... 3149.2B Table 3149.2-1, Select Granular Material (Super Sand) B.5 Select Granular Embankment Modified 10 percent ........................................... 3149.2B Table 3149.2-1, Select Granular Material Modified 10 percent B.6 Stabilizing Aggregate ......................................................................................... 3149.2C

B.7 Topsoil Topsoil is the existing Material within the construction limits that is suitable for plant growth and that originates from the A and/or B horizon soils. Peat and other O rganic Soils may be used to supplement the existing topsoil, if approved by the Engineer. Topsoil is included as a portion of the total common embankment outside of the Road Core. B.8 Non-structural Embankment Mineral soils, excess topsoil, and Organic Soils capable of supporting construction Equipment. Non-structural embankment is included as a portion of the total common embankment outside of the Road Core.

2106.3CONSTRUCTION REQUIREMENTS

A General Before beginning excavation and embankment operations, comply with the requirements of 2101, “Clearing and Grubbing.” Comply with the erodible surface requirements of 2574, “Soil Preparation.” Strip, stockpile and reuse in-place topsoil in areas to be disturbed by construction. For Road Core embankment, below granular or base Layers, use Material meeting the requirements of 2106.2B.1, “Common Embankment.” Non-structural grading Materials may be used as embankment outside the Road Core. Perform excavation and embankment operations within the Plan excavation limits as required by the Contract. Maintain drainage in excavations and embankment operations . Provide and maintain temporary drainage facilities until the permanent facilities are complete and operational. Do not leave undrainable depressions. Provide and maintain temporary preparation and erosion control on embankment and stockpiles until finishing operations per 2106.3I, “Finishing Operations,” are complete. Repair or replace settlement plates damaged by Contractor operations or negligence. Protect Structures during construction operations. Repair Structures damaged by Contractor operations. Excavated Material from within the Project limits shown on the Plans that meet Project requirements and complies with 1405, “Use of Materials Found on the Project,” may be used for embankment Material. Place stabilizing Aggregate in accordance with 2211, “Aggregate Base.” Forms and the Grading and Base Manual are available on the Department Grading and Base Website. B Contractor Quality Control (QC) Testing and Aggregate Certification Test according to the Schedule of Materials Control. Certify Materials on Form G&B-104.

Material placed without certifications is unauthorized Work in accordance with 1512, “Unacceptable and Unauthorized Work.” C Moisture Control Meet the moisture content requirements during compaction listed in Table 2106.3-1. Table 2106.3-1 Moisture Content Requirements For Compaction Requirements Relative Moisture Content Requirements* Minimum of 100 percent of Maximum Density 65 – 102 percent Minimum of 95 percent of Maximum Density 65 – 115 percent Quality compaction 65 – 102 percent * As determined on Form G&B-105

Correct moisture content in areas where moisture content test fails. Compaction tests taken in areas represented by failing moisture tests are not valid. D Preparation of Embankment Foundation When slopes are steeper than 1:4 (Vertical:Horizontal), construct steps before placing embankment Material. Construct the steps with a minimum width of 12 inches and a maximum height of 24 inches. Compact the bottom of the excavation according to Table 2106.3-2. Table 2106.3-2 Required Compaction for Bottom of Excavation Excavation Depth Below Grading Grade * Material Type Required Compaction < 30 inches non-granular 100 percent of Maximum Density, LWD, and Quality Compaction ≥ 30 inches non-granular 95 percent of Maximum Density or four passes of a roller ǁ Any depth granular 100 percent of Maximum Density, LWD, penetration index, and Quality Compaction For Structures any depth non-granular 100 percent of Maximum Density, LWD, and Quality Compaction For Structures any depth granular 100 percent of Maximum Density, LWD, penetration index, and Quality Compaction * Excavation below the planned Subgrade may be subject to 1402, “Contract Revisions” ǁ Use a pad foot roller weighing at least 25,000 pounds. The Engineer may waive the four pass requirement if the Subgrade will not support the roller or direct the Contractor to repair the Subgrade. Repairs are subject to 1402.5, “Extra Work.”

Remove surfacing and excavate an existing Road Core in accordance with the Contract. Then perform Subgrade preparation on the excavated portion and the new Road Core in accordance with 2112, “Subgrade Preparation,” before placing new embankment Material. E Excavating Operations Obtain the Engineer’s written approval before excavating beyond the limits and elevations established by the Contract.

Remove topsoil and stockpile separately. Remove rock outcroppings from within the excavation limits as shown on the Plans. Remove loosened rock from the backslopes. Presplit rock back slopes steeper than 1:1 (Vertical:Horizontal). Control blasting operations to eliminate flying rock or debris. Excavation below the planned Subgrade to correct unstable conditions may be subject to 1402, “Contract Revisions.” F Placing Embankment Materials Remove snow, ice, and frozen soils from Road Core before placing embankment. Install settlement plates, if required by the Contract. Do not disturb settlement plates. Place embankments in uniform Lifts, parallel to the Plan Profile Grade, over the full width of the Roadway. Construct each Lift of Material using uniform soil. Protect Structures during placement of embankments. Place granular Materials in the uppermost portion of the Subgrade. Embankment Materials may not increase the moisture content of the underlying Material beyond the specified limit. Maximum Lift thicknesses are controlled by the capability of the Equipment to uniformly compact the entire Lift in accordance with the following:

than 12 inches (loose thickness), when uniform results are not achieved.

loose).

thicker Lift must be at least 4 feet below the Grading Grade. Uniformly blend the entire thickness of each Lift before testing moisture content and compaction. Disc soils with greater than 20 percent passing the No. 200 Sieve. Stagger construction traffic uniformly over the full width of the Roadway embankment.

Use embankment Material with particle sizes no larger than specified in Table 2106.3-3: Table 2106.3-3 Maximum Particle Size in Road Core Location Maximum Particle Size (Inches) < 12 inches from Grading Grade 3 1 foot – 3 feet from Grading Grade 6 > 3 feet – 6 feet from Grading Grade 12 > 6 feet from Grading Grade 24 ≤ 2 feet from a non-plastic Structure 3 ≤ 2 feet from a plastic Structure 1 Areas where piling is to be placed 6

Remove surcharges as directed by the Contract. Remove debris and stones exceeding 3 inches in its greatest dimension on the soil surface at the time of performing the final finishing and turf establishment operations. Dispose of debris and stones in accordance with 2104.3C, “Removal Operations.” Removal of pre-existing debris and stone encountered in the undisturbed topsoil on the Project will be paid for as Extra Work in accordance with 1402, “Contact Revisions,” as long as the Material was not contaminated or altered by the Contractor. G Compacting Embankments and Backfills Compaction tests taken in areas represented by failing moisture tests are not valid. Uniformly compact each Lift according to Table 2106.3-4. Table 2106.3-4 Required Compaction Material Type Location Required Compaction * Materials meeting the requirements of 3149.2B, “Granular and Select Granular Materials” All depths and locations 100 percent specified density, Quality Compaction, penetration index, and LWD Materials not meeting the requirements of 3149.2B, “Granular and Select Granular Materials” > 3 feet below Grading Grade of Road Core, trails, or Sidewalks 95 percent specified density, and LWD when the Engineer performs a correlation test between 95 percent specified density, and an LWD. Materials not meeting the requirements of 3149.2B, “Granular and Select Granular Materials” ≤ 3 feet below Grading Grade of Road Core, trails, or Sidewalks 100 percent specified density, Quality Compaction, and LWD All Materials All depths within an excavation trench and backfill of Structures, 2451, “Structure Excavations and Backfills” 100 percent specified density, Quality Compaction, and LWD *See 2106.3G.1, “Specified Density,” 2106.3G.2, “Quality Compaction,” 2106.3G.3, “Penetration Index,” and 2106.3G.4, Light Weight Deflectometer (LWD) Method” for compaction requirements.

Compact Roadway embankment outside of the Road Core to the Quality Compaction requirements per 2106.3G.2, “Quality Compaction.”

Compact the entire length and width of each Lift with a roller. Construction traffic does not replace the rolling requirement. Compaction requirements on swamp backfills start when the Road Core embankment is 4 feet above the water elevation at the time of construction operations. The Engineer may waive mechanical compaction requirements on embankment containing predominately rock. Compact soils around Structures with appropriate Equipment or hand methods to prevent damage to adjacent Structures. Correct or replace Materials in areas represented by a failing test. Maintain the required compaction until the next Layer is placed. G.1 Specified Density Compact to meet the requirements of Table 2106.3-4. G.2 Quality Compaction Compact each Lift until there is no evidence of consolidation during compaction or under traffic, with no:

directly under the vehicle tire

G.3 Penetration Index (PI) Compact the entire Lift to achieve a dynamic cone penetration index (DPI) value per Table 2106.3-5. Table 2106.3-5 Maximum Allowable Penetration for DCP Grading Number * Moisture Content ǁ Maximum Allowable DPI, millimeter/blow 3.1 – 3.5 < 5.0 10 5.0 – 8.0 12 > 8.0 16 3.6 – 4.0 < 5.0 10 5.0 – 8.0 15 > 8.0 19 4.1 – 4.5 < 5.0 13 5.0 – 8.0 17 > 8.0 21 4.6 – 5.0 < 5.0 15 5.0 – 8.0 19 > 8.0 23 5.1 – 5.5 < 5.0 17 5.0 – 8.0 21 > 8.0 25

Grading Number * Moisture Content ǁ Maximum Allowable DPI, millimeter/blow 5.6 – 6.0 < 5.0 19 5.0 – 8.0 24 > 8.0 28 * As determined by Form G&B-203 ǁ Percent of dry weight Note that a moisture test is not required if the Material meets the toughest requirements for the grading number. G.4 Light Weight Deflectometer (LWD) Method Compact the entire Lift to achieve an LWD target value as required per the LWD procedure in the Grading and Base Manual. H Department Quality Assurance Testing (QA) Test according to the Schedule of Materials Control. H.1 Material Testing Select Aggregate quality samples using the random sampling method in the Grading and Base Manual; additional samples and tests may be taken to delineate visually indicated Material failures. Select gradation samples from locations that are at risk of not meeting the S pecification requirements. H.2 Compaction Testing Test for compaction using:

meeting the requirements of Table 3149.2-1, Granular Material, or

Materials meeting the requirements of Table 3149.2-1, Granular Material Test for compaction in areas with the greatest rutting or deflection, nearS tructures, and in an area at least 1 foot from an unconfined edge. After Contractor’s correction of areas represented by failing tests, retest in areas with the greatest rutting or deflection. For granular Materials with less than 6 percent passing the No. 200 Sieve, the Engineer may elect to only use the Quality Compaction method, 2106.3G.2, “Quality Compaction.” Use the specified density method for virgin Materials only. The following method may be used in lieu of point testing (penetration index, specified density, or LWD) for Materials meeting Table 3149.2-1, Select Granular Material when the Material thickness is 18 inches or less and when not adjacent to Structures per 1103, “Definitions.” The Engineer may elect, with the concurrence of the Contractor, to have the Contractor test roll per 2111, “Test Rolling,” Material meeting the requirements of Table 3149.2-1, Select Granular Material, in lieu of point compaction testing. If this method is adapted, the Contractor would be required to first place 3 inches of base on top of the Material meeting Table 3149.2-1, Select Granular Material before Test rolling. For areas failing Test rolling the Contractor is required to remove the base and recompact the Material meeting Table 3149.2-1, Select

Granular Material, then place the base back, and retest roll. There is no additional compensation to the Contractor, if this method is adapted. Additionally, the Material meeting Table 3149.2-1, Select Granular Material, is not accepted, until acceptable Test rolling has occurred. I Finishing Operations Shape and maintain the Road Core to the required grade and cross-section and within the tolerance in accordance with 2112.3E, “Tolerances” until the next Layer is placed. Perform earthwork finishing and topsoil placement operations concurrently to allow for timely placement of erosion control items. Shape and maintain disturbed areas outside the Road Core to final grade before placing erosion control items. Scarify the surface to a minimum depth of 3 inches before placing topsoil. Complete topsoil preparation, erosion control, and turf establishment, as required by 2574, “Soil Preparation” and 2574.5C, “Establishing Vegetation and Controlling Erosion.” J Disposition of Excavated Material Excavation and embankment Material not utilized on the Project becomes the property of the Contractor, except obtain written authorization from the Engineer before removing topsoil or granular Material from the Project. Dispose of these Materials in accordance with a disposal Plan approved by the Engineer. The disposal Plan must comply with applicable environmental regulations, permit requirements, and 2104, “Removing Pavement and Miscellaneous Structures.” Disposal of Materials before acceptance of the disposal Plan is unauthorized Work in accordance with 1512, “Unacceptable and Unauthorized Work.”

2106.4METHOD OF MEASUREMENT

A Excavation Material The Engineer will measure and calculate excavated Material quantities according to 1901.5A “Excavated Volume (EV) – Cubic Yard.” Quantities are limited to measurements within specified construction limits and variances authorized by the Engineer. The Engineer will take measurements to determine the limits of excavation Material. A.1 Rock Excavation The Engineer will include the following in the measurement for rock excavation:

or stratum of rock

Plans

for hard rock types The Engineer will not provide an allowance for overbreak of pre-split backslopes. B Embankment Material The Engineer will measure embankment Material quantities by volume in accordance with 1901.5B, “Compacted Volume (CV) – Cubic Yard.” C Stabilizing Aggregate The Engineer will measure Stabilizing Aggregate quantities by volume in accordance with 1901.5B, “Compacted Volume (CV) – Cubic Yard” or by the ton, in accordance with 1901.6, “Mass.”

2106.5BASIS OF PAYMENT

Embankment, such as required for additional backfilling a muck excavation, may be subject to the provisions of 1402, “Contract Revisions.” The Contract Unit Price for accepted quantities of Excavation and Embankment – compacted volume method items includes: the costs of production, testing, disposal, delivery, placement, drying, water and watering, compaction, and finishing. The Department will pay for stripping and stockpiling topsoil as excavation – common. The Department will pay for placing topsoil as common embankment . The cost for Subgrade preparation under 2106.3D, “Preparation of Embankment Foundation,” is included in the excavation 2106, “Excavation and Embankment – Compacted Volume Method,” bid items. A Monetary Adjustments The Department must apply Incentives and Disincentives and may apply monetary deductions for Excavation and Embankment – Compacted Volume Method. The amounts of these adjustments are deemed reasonable. The Department will pay an additional $2.00 per cubic yard when the Engineer reclassifies Excavation - common to Excavation - channel and pond. The Department will pay an additional $200.00 per cubic yard when the Engineer reclassifies Excavation - common, Excavation - Subgrade, or Excavation - channel and pond to Excavation - rock. The Department can only apply this price adjustment if the Contract does not contain Rock excavation and cannot exceed 250 cubic yard. The Department will pay an additional $200.00 per cubic yard when the Engineer reclassifies Excavation - channel and pond to Excavation - rock channel. The Department can only apply this price adjustment, if the Contract does not contain Rock channel excavation and cannot exceed 25 cubic yard. The Department will make monetary price adjustments for Excavation - Muck in accordance with. Table 2106.5-1. Table 2106.5-1 Monetary Price Adjustments for Excavation – Muck Muck Location Compensation Areas Where Muck is Shown in the Plan For the muck located at a depth between 0 to 5 feet below the Plan Depth Muck Excavation Unit Price For the muck located at a depth between 5 to 15 feet below the Plan Depth Muck Excavation Unit Price plus $2.00 per cubic yard For the muck located at a depth greater than 15 feet below the Plan Depth Negotiated Price

Muck Location Compensation Additional Areas Where Muck is not Shown in the Plan For the muck located between 0 to 10 feet below the Subgrade Excavation Muck Excavation Unit Price For the muck located at a depth greater than 10 feet to 20 feet below the Subgrade Excavation Muck Excavation Unit Price plus $2.00 per cubic yard For muck located at a depth greater than 20 feet below Subgrade Excavation Negotiated Price In addition to the monetary price adjustments listed above, compensation for additional muck excavation may be subject to the provisions of MnDOT 1402, “Contract Revisions” if additional shoring, dewatering, requisition of additional disposal site(s) because of increased volume of muck, or additional hauling beyond original disposal site(s), or other related activities are required. B Schedule The Department will pay for Excavation and Embankment – compacted volume method on the basis of the following schedule: Item No. Item Unit

2106.507 Excavation – Common cubic yard

7 Excavation – Rock cubic yard

7 Excavation – Muck cubic yard

7 Excavation – Subgrade cubic yard

7 Excavation – Channel and Pond cubic yard

7 Excavation – Rock Channel cubic yard

7 Granular Embankment (CV) cubic yard

7 Select Granular Embankment * (CV) cubic yard

7 Select Granular Embankment Super Sand (CV) cubic yard

7 Common Embankment (CV) cubic yard

7 Stabilizing Aggregate (CV) cubic yard

9 Stabilizing Aggregate Ton

Notes: * Specify basis of percent modification (e.g. 5 percent, 7 percent, 10 percent, etc.)