Section 152 — Construction Survey and Staking
Description
152.01This work consists of surveying, staking, calculating, and recording data for the control of work. See FAR Clause 52.236-17 Layout of Work.
Construction Requirements
152.02Qualifications. Provide technically qualified survey crews experienced in highway construction survey and staking. Provide personnel who can perform in a timely and accurate manner. At least 14 days before starting survey and staking work, submit a résumé for each indivi dual. Include the following if AMG methods are used:
(a)The name, authority, relevant experience, and qualifications of the person with overall responsibility for the AMG system; and
(b)The names, authority, and relevant experience of personnel directly respons ible for operating the AMG equipment.
152.03Submittals. At the preconstruction conference, submit a price breakdown by individual tasks if construction survey and staking is paid by the lump sum for use in making progress payments. Submit the following i f AMG methods are used:
(a)Technology statement. A written statement that includes:
(1)The manufacturer, model, and software version of the AMG equipment; and
(2)Certification that the final Government -furnished 3D data is compatible with the AMG equipment.
(b)QCP. Describe procedures for checking, mechanical calibration, and maintenance of both survey and construction equipment. Include the frequency and types of checks performed.
152.04General. Provid e a crew supervisor on -site when surveying and staking is in progress. Provide survey instruments and supporting equipment that can achieve the specified tolerances. If approved, construction equipment controlled with a GPS or Robotic Total Station (RTS) machine guidance system may be used in the construction of subgra de, subbase, and base aggregate courses, or other construction operations. Provide acceptable tools and supplies of the type and quality suitable for highway survey work. Provide stakes and hubs of sufficient length to provide a solid set in the ground wit h sufficient surface area above ground for necessary legible and durable markings. Include staking activities in the construction schedule according to Section 155. Include the dates and sequence of each staking activity. The Government may set initial horizontal and vertical control points for the project. If the Government sets initial horizontal and vertical control points, the Government will provide data for use in establishing control for completion of the work. If the Contractor is tasked with setting initial horizontal and vertical control for the project, provide the contractor- established control network to the Government for verification. The Government wil l furnish data relating to horizontal and vertical alignment, theoretical slope stake catch points, and other miscellaneous design data. Reformatting and additional calculations may be required for the convenient use of the Government -furnished data. Provi de immediate notification to the CO of apparent errors in the initial staking or in the Government- furnished data. Record survey and measurement field data in an approved format. Submit as -staked data and corrections made to the Government -furnished survey data. Submit survey and measurement data at least weekly while surveys are being conducted. Field data and supporting documentation become the property of the Government upon completion of the work. Discuss and coordinate the following with the CO before surveying or staking:
(a)Surveying and staking methods;
(b)Stake marking;
(c)Grade control for courses of material;
(d)Referencing;
(e)Structure control;
(f)Field staking data;
(g)Localization of the GPS systems to the Government- established control points; and
(h)Other procedures and controls necessary for the work. Do not start work until staking or 3D verification data for the affected work has been approved. Preserve initial reference and control points. Notify the CO of missing control points or stakes at least 10 days before starting construction. Reestablish initial control points and obtain approval before starting construction. Acceptance of the construction staking does not relieve the Contractor of responsibility for correcting errors discovered during the work an d for bearing additional costs associated with the error. Maintain legibility of stake markings for the duration of the project or until notified in writing the stakes are no longer needed. Replace stakes as necessary to ensure markings are maintained. Rem ove and dispose of flagging, paint, lath, stakes, and other staking material after the project is complete. Compute and provide calculations supporting pay quantities. Measure quantities within the tolerances established by the CO according to Section 109. 64 152.05 Survey and Staking Requirements. Perform survey, staking, recording of data, and calculations as necessary to construct the project. Survey and set stakes to the tolerances shown in Table 152-1. Reset stakes and hubs as required and maintain in an acceptable condition for the duration of the project or until notified they can be removed. Notify the CO if errors are discovered.
(a)Control points. Relocate initial horizontal and vertical control points in conflict with construction to areas that will not be disturbed by construction operations. Provide the coordinates, elevations, and supporting documentation for the relocated points before the initial points are disturbed. Set durable monuments for survey control that uniquely identify the points according to Subsection 107.02 and Section 621. Notify the CO at least 10 days before disturbing original monumentation to verify the newly set control. Provide the GPS localization results or total station check shot data at least 10 days before starting construction layout work. The CO may order the GPS localization calibration and associated 3D model to be broken into two or more zones to maintain the localized relationship between control points and original ground.
(b)Centerline establishment. Establish or reestablish centerline at roadway design cross- section locations and as necessary to construct the work. Reestablish the centerline if construction survey and staking work does not meet the tolerances.
(c)Original ground topographic verification. Use an approved method to verify existing ground survey. In areas where theoretical and actual ground elevations do not meet a tolerance of ±0.5 feet, notify the CO as resurvey may be required. Re -measure 3D data to verify existing ground topography to mapping. Submit 3D data in electronic format. Re-measure 3D data 10 feet beyond catch points to verify existing ground topography.
(d)Slope and references stakes. Perform the following:
(1)AMG method. After clearing operations are completed, set centerline reference stakes and hubs on both sides of centerline at 100-foot intervals at the clearing limit locations. Where clearing limits are greater than 10 feet vertically, 25 feet horizontally, or both from subgrade hinge point; provide an additional reference stake and hub as approved. Label each centerline reference stake with station, hub elevation, and offset from centerline. Construct a 1000-foot- long test section using AMG at an approved location before starting grading operations. Select a test location with superelevation and curve widening transitions if applicable. Notify the CO 10 days before starting the test section. Demonstrate capability, knowledge, equipment, and experience to achieve work within tolerances. Allow 14 days to evaluate the test section. Do not start full grading operations until the test section is approved. Visibly delineate or mark the centerline reference stakes and hubs at cross- section locations for use in verifying grade and elevation. Use conventional survey methods at random locations specified by the CO, no more than 500-foot intervals. Submit 3D coordinates of centerline reference stakes and hubs QC checks. If QC checks do not meet the tolerances in Subsection 204.13(c) , rework the section until the specified tolerances are achieved and provide additional cross- sections as directed.
(2)Conventional survey methods. Verify and set slope stakes on both sides of centerline at the theoretical catch point. If the theoretical catch point is not within a tolerance of ±0.5 feet, perform original ground topographic verification according to Subsection 152.05(c) . Set the slope stake at the actual intersection of the design roadway slope with the natural ground- line. Set reference stakes outside the clearing limits. Include reference points and slope stake information on the reference stakes. At minimum, label each slope stake with grade information to subgrade shoulder, station, hub elevation, and offset from centerline. Include other relevant information on the stakes if requested. Estab lish slope stakes in the field as the actual point of intersection of the design roadway slope with the natural ground- line if theoretical catch point information is not available.
(e)Clearing and grubbing limits. Before ground disturbance occurs, set clearing and grubbing limits on both sides of centerline at least every 100 feet. Label each clearing and grubbing limit reference stake with station and offset from centerline .
(f)Grade finishing stakes.
(1)AMG method . Construct a 1000- foot-long test section using AMG at an approved location before starting grading operations. Select a test location with superelevation and curve widening transitions if applicable. Notify the CO 10 days before starting the test section. Demonstrate the capability, knowledge, equipment, and experience to achieve work within tolerances. Allow 14 days to evaluate the test section. Do not start full grading operations until the test section is approved. Visibly delineate or mark the centerline and shoulder catch point at cross -section locations for use in verifying grade and elevation. Verify the grade elevation and horizontal alignment of roadway grade- finishing operations. Use conventional survey methods at random locations specified by the CO, no more than 500-foot intervals. Subm it 3D coordinates of grade finishing QC checks.
(2)Conventional survey methods. Set grade finishing stakes for grade elevations and horizontal alignment, on centerline and on each shoulder at design roadway cross -section locations. Set stakes at the top of su bgrade and the top of aggregate course. Reset grade finishing stakes as many times as necessary to construct the subgrade and each aggregate course. During turnout or pullout construction, set stakes on the centerline, on each normal shoulder, and on the shoulder of the turnout. In parking areas, set stakes at the center and along the edges of the parking area. Set stakes in ditches to be paved. If the centerline curve radius is less than or equal to 250 feet, use a maximum longitudinal spacing between stak es of 25 feet. If the centerline curve radius is greater than 250 feet, use a maximum longitudinal spacing between stakes of 50 feet. Use a maximum transverse spacing between stakes of 20 feet. Use brushes or guard stakes at each stake.
(g)Culverts. Verify an d set culvert locations at the inlet, outlet, and inlet basin points as shown in the plans. Perform the following:
(1)Survey and record the ground profile along the culvert centerline and additional channel profile for an appropriate offset to capture require d information in Subsection 152.05(g) (4). 66 (2) Determine the slope catch points at the inlet and outlet.
(3)Set reference points and record information necessary to determine culvert length and end treatments.
(4)Plot to scale the profile along the culvert centerline. Show the natural ground, flow line, roadway section, culvert, end treatments, and other appurtenances. Show elevations, grade, culvert length, and degree of elbow.
(a)For single skewed culverts, submit a plotted field- design cro ss-section normal to roadway centerline and at each end section. Plot the offset and elevation of natural ground at the end section and at proposed template break points between centerline and the end section. Ensure the template design embankment slope is not exceeded.
(b)For multiple skewed culverts, submit a plotted field -design cross -section normal to roadway centerline and at the end sections (left and right) nearest to the shoulder. Plot the offset and elevation of natural ground at the end section and at proposed template break points between centerline and the end section. Ensure the template design embankment slope is not exceeded.
(c)Submit the plotted field -design cross -section for approval of final culvert length and alignment. Plot at a clear and readable scale.
(d)Set inlet, outlet, and reference stakes after the field design has been approved. Stake inlet and outlet ditches to ensure the culvert and end treatments (such as drop inlets) are functional.
(e)Adjust slope, reference, and clearing stakes as necessary to provide for culvert inlet treatments in cut slopes. Readjust slope, reference, and clearing stakes as necessary if culvert inlets are moved from their plan locations. Review slope adjustments with the CO and obtain approval.
(h)Bridges. Set adequate permanent horizontal and vertical control and reference points for bridge substructure and superstructure components to last through project construction. Establish and reference the bridge chord, bridge tangent, or control lines as shown in the bridge pla ns. Also establish and reference the centerline of each pier, bent, and abutment.
(i)Retaining walls, rockeries, special rock embankments, rock buttresses, gabion walls, and reinforced soil slopes. Survey and record profile measurements along the face of the proposed wall, rockery, embankment, buttress, or reinforced soil slope at 5 feet and 10 feet in front of the wall or slope face. Take cross -sections every 25 feet along the length of the wall or reinforced soil slope and at major breaks in terrain within the limits designated by the CO. Measure and record points every 25 feet and at major breaks in terrain for each cross -section. Set reference and control points to perform the work.
(j)Borrow and waste sites. Perform field work necessary for initial layout, ba seline, and measurement of the borrow or waste site. Establish site limits and clearing limits. Measure both original and final ground conditions and submit survey data as directed.
(k)Permanent monuments and markers. Perform survey and staking work necessary to establish permanent monuments and markers as described in Section 621 or reestablish monuments as described in Subsection 107.02.
(l)Miscellaneous survey and staking. Survey and stake other work as directed to the proper location and required tolerances. Propose staking increments and tolerances for approval if not shown in Table 152-1. Table 152-1 Construction Survey and Staking Tolerances(1)
Staking Phase Horizontal ,
feet (±) Vertical , feet (±) Control points set from existing control points 0.03 0.01 ×√𝑁𝑁 (2) Mapping, topography, & cross -section points 0.16 0.16 Centerline points(3) & references 0.06 0.06 Slope stake and slope stake references(4) 0.16 0.16 Culverts, ditches, & minor drainage structures stakes 0.16 0.06 Retaining walls stakes 0.06 0.03 Curb & gutter stakes 0.06 0.03 Bridge substructures stakes 0.03(5) 0.03 Bridge superstructures stakes 0.03(5) 0.03 Clearing & grubbing limit stakes 1.00 – Roadway subgrade finish stakes(6) 0.16 0.03 Roadway finish grade stakes(6) 0.16 0.03
(1)At statistical 95 percent confidence level. Tolerances are relative to existing Government control points.
(2)N is the number of instrument setups.
(3)Centerline points: point of curve (PC), point of tangent (PT), point on tangent, point on curve (POC).
(4)Take the cross -sections normal to the centerline ±1 degree.
(5)Bridge control is established as a local network and the tolerances are relative to that network.
(6)Includes paved ditches.
152.06Acceptance. Construction survey and staking will be evaluated under Subsections 106.02 and 106.04. Survey notes will be evaluated under Subsection 106.02. Permanent monuments and markers will be evaluated under Section 621.
Measurement
152.07Measure the Section 152 pay items listed in the bid schedule according to Subsection 109.02 and the following as applicable: When measuring grade finishing by the mile, measure one time for the subgrade and one time for each aggregate course. 68 When measuring survey and staking by the hour, do not measure time spent in making preparations, traveling to and from the project site, performing calculations, plotting cross -sections and other data, a nd processing computer data. Do not measure re -establishing missing control points or stakes after construction operations have begun.
Payment
152.08The accepted quantities will be paid at the contract price per unit of measurement for the Section 152 pay items listed in the bid schedule. Payment will be full compensation for the work prescribed in this Section. See Subsection 109.05 . Progress payments for lump sum pay items will be prorated based on total work completed under this Section .