PennDOT Special Provision Contractor Support of Research Project. SUBGRADE SOILS (Type II)

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1 PennDOT Special Provision Contractor Support of Research Project SUBGRADE SOILS (Type II) Intelligent Compaction Pooled Fund Accelerated Implementation of Intelligent Compaction Technology for Embankment Subgrade Soils, Aggregate Base and Asphalt Pavement Materials Description: The purpose of this Special Provision is to describe additional work (roller transportation/security, materials, equipment, and operators) by the Contractor to support this research project, which will be conducted during placement and compaction of subgrade soils. The purpose of the research study is to demonstrate Intelligent Compaction (IC) technology, to evaluate the benefits of IC technology for compaction of subgrade soils compared to conventional compaction equipment/practices, to accelerate the development of IC specifications and to identify/prioritize needed improvements and research in IC equipment. The IC test results will not be used for approval or rejection of the project materials testing but will be only used to support the research study. IC for Soils is defined as the gathering of data from self-propelled vibratory system involved with the measurement and recording of roller position, date/time, speed, vibration frequency, vibration amplitude, pass count, travel direction, and compaction measurement value. Real Time Kinematic (RTK) based Global Positions System (GPS) is to be used for determines the position of the rollers and mapping of IC measurements. I. Time Frame The IC research team will be conducting experiments for approximately five to six consecutive working days. The consecutive working days do not include days when work cannot occur due to weather conditions. The specific dates that the support work is needed will be established during the IC research project pre-construction meeting at least two weeks in advance of the work. For planning purposes, the IC research team has targeted the IC field demonstration days after the notice to proceed is given. II. Equipment The IC research team will provide the IC roller(s) and Global Positioning System (GPS) equipment at no cost to the project. Depending on the type of materials to be use as part of the project a smooth drum and/or padfoot drum rollers will be utilized by at least two different manufactures. The Contractor will be responsible for onsite 1

2 transportation of the rollers to the designated construction site(s) and to the PennDOT Open House which will be within relatively close proximity to the project as discussed during the pre-construction meeting. If necessary, the roller will be transported by the Contractor to a secure area during non-working hours. To support the IC research operations a GPS System, up to 200 gallons of diesel fuel will be needed, plus testing personnel and construction equipment is also needed as described below. a. Test Bed Preparation During test bed preparation, equipment provided by the Contractor shall consist of sufficient haul trucks, water truck, grader and disc (if deemed necessary) to place the materials, to introduce and blend sufficient water into the materials to obtain uniform moisture content and to level the materials in uniform lifts at the thickness designated by the IC research team. Where possible, the equipment used on the research test beds will be the same equipment used on the remainder of the project. The Contractor's equipment and operators will generally be needed for approximately two to three hours per day. For the remainder of the day, the Contractor may use the equipment on the remainder of the project. The IC research team will compact the test bed materials placed by the Contractor. b. Compaction Section Preparation During compaction section construction, there will be no additional equipment needs from the Contractor. Placement, moisture conditioning and grading of the materials in the test sections will be performed with equipment and methods as normal. The Contractor s rollers and operators will not be needed during compaction of the test section materials. Compaction of the test section material will be performed by the IC research team equipment and operators. III. Operators Operators provided by the Contractor will consist of qualified and skilled individuals that are familiar with the operation of the equipment assigned to them. The operators shall coordinate with the IC research team during placement of the test beds to ensure that material types, percentage and uniformity of moisture content and lift thickness are satisfactory. IV. Communication with IC Research Team At least once a day, the IC research Team will meet with the Contractor's project manager to plan and coordinate the support work. At the time of the meeting, the IC research team will provide clear instructions on the location, materials types, desired moisture content, lift thickness and other details of the preparation of the test beds, compaction sections and/or other types of preparation. The Contractor is requested to keep the IC research team aware of project changes that may effect the IC operations. 2

3 The Contractor field staff is encouraged to visit the IC Mobile Testing Laboratory at any time. V. Test Bed Construction During test bed construction, contractor equipment and operator time to place, moisture condition and grade the test bed material will be needed for about two-three hours per day. The IC research team will compact the test bed materials. The test beds shall be feet in width and ft in length and will consist of a single lift of subgrade, subbase or base material (see Figure 1). The Contractor shall place these materials and mix carefully to meet specific lift thickness and moisture contents. Various moisture contents will be specified by the IC research team between optimum 4% and optimum + 4%. The tolerances on specified mixing depths and moisture contents are ± 2 inch and ± 2%, respectively. 1 Roller lanes ft ft Fig. 1 Layout of test beds. Contractor place material to desired thickness and moisture condition material to optimum 4% and optimum + 4% and values in between and mix with discs or reclaimer (depending on material). The approximate number and location of the test bed(s) will be established at a preconstruction meeting. Test bed locations will be selected to be out of the way of normal contractor operations and near the IC Mobile Laboratory. This work will be scheduled at times that are convenient for the Contractor and the IC research team. During the construction of the test bed, the IC research team will work with contractor personnel to verify the material type, to measure lift depth and to determine the percentage and uniformity of moisture content in a timely manner. The IC research team will place inground instrumentation prior to the placement of the test bed material. The IC research team will approve the test bed placement before the equipment is removed from the test bed location. At the completion of the research project, the test beds may be left in place at the discretion of the Contractor. The IC research team will not be responsible for meeting any of the specific project material, density or moisture content requirements. 3

4 VI. Compaction Section Construction During compaction section construction, the Contractor will perform normal compaction operations on three areas of selected subgrade, subbase and/or base course sections using IC rollers. In these sections, the Contractor will not be required to provide extra rollers or operators to perform the compaction. The IC research team will evaluate the test areas of embankment, subbase and/or base course (full earthwork width by ft long) as shown in Fig. 2. The Contractor shall place the materials and conduct and conduct what every tests they would do to meet the standard QC/QA requirements of the project. The IC research team will perform IC roller calibration testing over a 100 ft long section where nuclear gage moisture-density, light Weight Deflectometer (LWD) and other data are compared to roller measurement, followed by compaction of the remainder of the ft long section. The IC research team will perform moisture, density and other spot testing in the calibration area (10-20 points) and in the larger section (10-20 points) per section. The specific number and general locations of the compaction sections will be established in the pre-construction meeting. If possible multiple lifts of subgrade and/or aggregate base courses in each compaction section can be evaluated. Full width ~ 2000 ft Calibration area (full width X 100 feet) Fig. 2 Plan view of Compaction Sections. Contractor prepares ft section of embankment, subbase or base as they normally would. The IC research team then calibrates the IC roller with density testing in the calibration area (~2 hours) using the IC roller(s). Research team then performs additional density testing in the areas. The PennDOT is requested to provide the IC research team their QA results in the IC testing areas for comparison with the IC results. The IC results are available to the PennDOT or the Contractor at anytime during the field demonstration. VI. ISU Mobile Testing Laboratory The Intelligent Compaction evaluations will be performed in a mobile field laboratory owned and operated by Iowa State University (ISU) at no cost to the project. The trailer will be moved onto the project and set up in a convenient location prior to the 4

5 demonstration. The Contractor shall provide a suitable location with a solid platform approximately 50 feet long and 15 feet wide for the mobile laboratory. The exact location will be selected during the pre-construction meeting. The laboratory will remain in that location for the duration of the research activities. The Contractor is responsible for providing electrical connections, drinking water, and sanitary facilities during the IC field demonstrations at the laboratory site. The laboratory site also needs sufficient parking for the IC research team construction vehicles and sufficient area for visitors. A parking area to support 10 vehicles should be sufficient. VII. Global Positing System Intelligent Compaction rollers are dependant on availability of a Global Positioning System (GPS) to track roller positions during operations in order to display color-coded maps of roller pass counts, roller-integrated measurement values (RMV), and other measurements such as surface temperatures. The use the Universal Transverse Mercator Coordinate (UTM) is the preferred coordinate system. The UTM zone for Pennsylvania site is 17N or 18N depending on the location of the project. The GPS base station shall broadcast differential correction data to the rollers and hand-held rovers with tolerance of less than 40 mm in both horizontal and vertical directions. VIII. Method of Measurement (The DOT needs to decide if their will be additional payment or not for the IC work and revised this and the next section accordingly.) This work will be not be measured as the item will be lump sum for providing assistance for and performance of the research project. IX. Basis of Payment Payment will be full compensation for materials, equipment, and operators, any delay during testing program, site preparation, and use of GPS system, water tank, discing to control moisture content or any other services required for progress of the Intelligent Compaction research program. Payment will be made under: Pay Item Unit IC Compaction Research... LS 5