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Furnish, place, and maintain construction layout stakes. Demarcate (flag) the Limit of Disturbance (LOD), and protected resources including, wetlands, wetland buffers, waters of the United States, floodplains, and tree preservation areas.
The LOD is defined as the maximum allowable limit of earth disturbance as delineated in the Contract Documents. When not delineated in the Contract Documents, the LOD will be the top of cut, toe of slope, or limit of ditch excavation.
No clearing or earth disturbance activity may begin until the LOD and all protected resources are demarcated as specified.
Refer to 107.03.09.
107.03.01 Line and Grade. The Engineer will provide the following:
(a) Roadway Stakeout
(1) A staked center line of the roadway with stations not over 100 ft apart.
(2) Appropriately spaced bench marks and necessary references, including all points of curvature (PC) and points of tangency (PT), for the preservation and control of the center line.
(3) Two sets of prints of the cross sections. Use the cross sections as a guide only. Dimensions or elevations scaled from the cross sections are not sufficiently precise for use in construction.
(b) Structure Stakeout
(1) A staked center line or working line, whichever applies, with stations not over 100 ft apart and extending at least 100 ft beyond each end of the structure.
(2) When the structure is on a curve, a staked center line or working line, whichever applies, consisting of stations not over 100 ft apart and including the PC, PT, and at least one point on the tangents beyond each end of the curve.
(3) At least two bench marks, one on each end of the structure.
107.03.02 Equipment and Personnel. Use competent personnel and state-of-the-art equipment for all engineering work required to set and maintain the specified elevations and dimensions.
107.03.03 Control Markers. Preserve the center line and bench marks set by the Engineer. Replace any disturbed or destroyed controls at no additional cost to the Administration.
107.03.04 Control Stakes. For roadways as specified in 107.03.01(a), furnish, set, and preserve stakes at each station along each side of the project on the right-of-way or easement line, whichever is farther from the center line of construction. Where only part of an ultimate dual highway is to be constructed, set the stakes on the side of the future improvement 10 ft beyond the construction limits. On each of these stakes, mark the offset distance from the center line and its top elevation or the cut or fill to the profile grade line. Place additional stakes as necessary or as directed to ensure the correct layout of the work.
107.03.05 Layout. For structures, proceed with the layout work as specified in 107.03.01(b). Before any actual construction begins, rerun and check the Engineer's lines and grades. Then establish all center line or working line intersections with the center line or center of bearing of all piers, bents, and abutments. From these field layouts, check the proposed span lengths by either electronic distance measurement or chaining from the field layouts. When chaining, compensate for temperature, sag, and horizontal alignment. Check the location of the structure to affirm its correct location with relation to existing structures, roads, and existing conditions that are to remain. If any discrepancies are found, notify the Engineer at once in writing. Ensure that all lines established on the ground are preserved or referenced, marked, and kept available at all times.
Ensure that the field elevations of all bridge seats are correct and that they are finished to proper grade. When steel beams or girders are incorporated in the project, determine the deflection of each member by running elevations over the tops of the beams or girders after they are in place and before attaching any forms. Apply this information to the deflection diagram to determine the corrected elevation of bottom slab forms and screed supports. The Engineer will check the assembled information. Make necessary adjustments prior to placing concrete.
107.03.06 Utilities. Promptly upon request, furnish references to control points, alignment, and grade data to the utility companies or agencies working within the limits of the project, so that they may properly locate and coordinate their work and improvements.
Intersection Utility Stakeout. Notify the appropriate agencies at least 72 hours (excluding weekends and holidays) prior to the anticipated time for beginning any underground work.
(a) Request a MISS UTILITY stakeout and possess a valid MISS UTILITY clearance ticket number for any underground work.
(b) Contact all utilities within the limits of the project who are not a member of MISS UTILITY and obtain a stakeout of their respective facilities.
(c) Request the Office of Traffic & Safety’s Signal Operations Section to stakeout Administration maintained traffic signal facilities.
(d) Request the District Engineer to stakeout their lighting facilities.
Stakeout the proposed construction as indicated in the Contract Documents. Allow the Engineer to verify the location of the proposed facilities.
107.03.07 Right-of-Way and Easement Lines. Promptly upon request, define the project right-of-way and easement lines for adjacent property owners.
107.03.08 Subgrade, Subbase and Base Controls. When placing subgrade, subbase, and base courses, furnish a string line and grade with fixed controls having longitudinal and transverse spacing of no more than 25 ft. Along each form line for cement concrete pavement, provide the line and grade with fixed controls not to exceed 25 ft.
(a) Automated Machine Control. When approved by the Engineer, construction equipment guided by Global Positioning System (GPS) or Robotic Total Station (RTS) equipment may be utilized in the placement of subgrade, subbase, base courses, and other roadway materials. Preserve the stakeout established by the Engineer and set additional controls as directed.
(1) If utilizing GPS and RTS equipment, develop and submit a Digital Terrain Model (DTM) for review. If using the Contract Documents and any Administration furnished DTM data, a DTM shall be developed independently. In order to use any Administration furnished DTM data, the Administration and its designers shall be released from all liability for the accuracy of the data and its conformance to the Contract Documents.
(2) Establish primary control points at appropriate intervals along the length of the project. Where project work is performed beyond the project limits, establish control points at intervals not to exceed 1000 ft. Determine the horizontal position of these points by static GPS sessions or by traverse connection from the original base line control points. Establish the elevation of these control points using differential leveling from the project benchmarks, forming closed loops where practical. Prior to construction activities, provide a copy of all new control point information to the Engineer. Correct all deficiencies at no additional cost to the Administration.
(3) Provide control points and conventional grade stakes at critical points such as PCs and PTs, super elevation points such as begin full super and half-level plane inclined, and other critical points required for construction of structures and utility relocation or coordination. The Engineer will determine whether additional stakeout and control points are necessary.
(4) Provide adequate control points, stationing, and stakes for coordination activities involving environmental agencies, utility companies, and Contractors on adjacent projects.
(b) Real-Time Kinematic (RTK) GPS. May be utilized to control equipment where the grade tolerance is ±0.1 ft or greater.
(c) RTS Positioning. RTS shall be utilized where grade tolerances are less than ±0.1 ft. Check the index error of the vertical circle of the RTS and adjust as necessary prior to each day’s operations. Begin and end each work session by checking between adjacent control points.
(d) Grade Busts. Grade busts and all associated quantity adjustments or errors resulting from the Contractor’s activities shall be corrected and at no additional cost to the Administration.
(e) Utilizing Automated Controlled Equipment. When automated controlled equipment is used, furnish a GPS Rover instrument for Administration use during the project, along with 8 hours of formal training on GPS/RTS and the utilized systems. Provide a surveyor to perform verification when discrepancies arise.
(f) Test Sections. Perform test sections for GPS and RTS systems to demonstrate the capability, knowledge, equipment, and experience to properly operate the systems and achieve acceptable tolerances. If this ability is not demonstrated, conventional stakeout procedures will be required.
107.03.09 Demarcation. Perform all demarcation as specified or directed. Demarcate wetlands using the Administration’s standard 1-1/2 in. pink and white striped vinyl flagging with “SHA WETLAND” printed in blue letters. Demarcate the LOD and other applicable protected resources using a minimum 2-mil vinyl that is 1-1/2 in. wide with 7/8 in. letters, and locate as directed.
Establish tree preservation areas as specified in Section 120.
When directed, reflag areas where flagging has been destroyed. If the destroyed flagging is not replaced within 48 hours, the Engineer may proceed to reflag the area. The cost of the reflagging by the Engineer will be deducted from any monies due under the Contract.
Remove all flagging at the completion of construction.
Construction Stakeout will not be measured but will be paid for at the Contract lump sum price. The payment will be full compensation for all material, labor, equipment, tools, and incidentals necessary to complete the work. Payment of the Contract lump sum price will be prorated and paid in equal amounts on each monthly estimate. The number of months used for prorating will be the number estimated to complete the work.