149.1General Description
Perform construction layout to guide and control performance of items of the work according to this specification. This work includes: •Placing, replacing (if necessary), and maintaining construction layout points. •Preparing construction layout drawings, sketches, and computations. •Recording data in field books such as alignment, slope stake, blue top, drainage layout, bridge, and other books used for layout for this p roject. 149.1.01 Definitions General Provisions 101 through 150 149.1.02 Related References A.Standard Specifications General Provisions 101 through 150 B.Referenced Documents General Provisions 101 through 150 149.1.03 Submittals Submit the following documentation to the Department: A.Project Construction Records These records detail information that the Department uses to determine the template line for the as -built cro ss s ections, which defines the computation line for unclassified excavation. These records include: •Survey records •Bound field notebooks •Computer printouts that record the Project’s construction •Prepare the records as directed by the Engineer. B.Survey Documents Furnish the Engineer with a copy of survey documents that relate to construction layout. Provide these documents when the Engineer requests or as they are completed. The Engineer may check the documents for accuracy andmay require revisions where necessary. The documents become Department property and will be included in the p ermanent p roject records. C.Drainage Structure Sketches Profile both inlet and outlet ends of proposed drainage structures for at least 100 ft . (30 m) in the existing ditch li ne or stream bed. Adjust flowline elevations, if necessary, to enhance the hydraulics and to reduce silting, scouring, or backwater. Calculate the length of each structure and provide sketches of the structure to the Engineer for review and approval at least 24 hours before beginning the work. 89 89 89 89 89 89 89 89 89 89
D.Bridge Layout Sketch Furnish a layout sketch before staking on bridges. After staking, submit a revised sketch for the Engineer’s revi ew and approval before beginning construction. Include in the layout sketch relevant stations, angles, dimensions, and redundant checks including exterior beam dimensions in each span. Also include all horizontal and vertical clearances with calculations that verify the clearances shown. Submit for the Engineer’s review and approval survey data and calculations with the layout sketch and informatio n r equired for bent construction. Verify the p lan elevations for all bridge bearing seats on the substructure. E.Wall Layout Sketches Submit sketches and other data verifying either that the wal l will fit the final field conditions or indicate wher e r evisions are necessary. Submit these sketches well before the wall construction begins so the Engineer can mak e any necessary structural design changes.
149.2Materials
General Provisions 101 through 150 149.2.01 Delivery, Storage, and Handling General Provisions 101 through 150
149.3Construction Requirements
General Provisions 101 through 150 149.3.01 Personnel Furnish personnel capable of establishing line and grade points necessary to complete the work. Establish these points within the generally accepted surveying tolerances and ensure that they are acceptable for the work being performed. 149.3.02 Equipment Furnish surveying equipment, stakes, and all materials necessary to perform the work, subject to the Engineer’s approval. 149.3.03 Preparation A.General Pre -Construction Before beginning construction: 1.Ensure that plan dimensions, alignment, and elevations are compatible with existing field conditions. Mak e ad justments where necessary. 2.Ensure alignment tie- ins by coordinating construction layout with that of other Contractors whose work abuts any portion of the work. All adjustments are subject to the Engineer’s approval. 90 90 90 90 90 90 90 90 90 90
B.Widening and Reconstruction Before beginning construction where existing pavement is to be retained either for widening or for reconstruction: 1.Take three- point levels of the pavement throughout the length to be retained. Normally, the three- point levels will be required at 50 ft. (15 m) intervals. However, the Engineer may adjus t thes e intervals according to existing field conditions. Three- point levels are not required on asphalt shoulder widening projects and earth shoulder reconstruction projects. 2.From the three- point levels, prepare a graphic grade plot that “best fits” the existing pavement to minimize the l eveling requirements (if any) of the existing roadway. Cross slopes may be varied within the ranges shown o n the plans or adjusted by the Engineer to produce the “best fit.” 3.On passing lane or widening Projects where existing pavement is not to be overlaid: a.Profile and plot the outside edge of the existing pavement to obtain a smooth profile grade. b.Transfer this grade to the new edge of paving using the proper cross slope. 4.Furnish data to the Engineer for approval before beginning widening and reconstruction. 5.O n widening, reconstruction, or passing lane projects, obtain the Engineer’s approval of the “best fit” profile. Ensure that grade stakes are set to control the construction of any required widening based upon the “bes t f it” profile and cross slope. Construct proposed widening flush with the existing edge of paving. Provide positive drainage in all cases. C.Existing Bridge Widening or Modification To widen or modify existing bridges, do the following before ordering materials or beginning construction:1.Verify existing elevations and dimensions as well as confirm or determine required new cap elevations. 2.Profile the removal line and cross section the existing deck. 3.Use this profile inf ormation to determine a “best fit” finished grade for the widened portion. 4.Compute the new cap elevations based on this “best fit” information. 5.Furnish survey data, layout sketch, and calculations to the Engineer for approval. D.Retaining Wall Construction Layout Set stakes, take necessary cross sections, and perform necessary calculations at each wall before beginning wall construction to ensure that the geometric design of the retaining wall conforms to actual conditions. 149.3.04 Fabrication General Provisions 101 through 150 149.3.05 Construction A.Verify Plan Elevations Verify plan elevations for all bridge bearing seats on the substructure. B.Verify Bent Layout After bent construction has begun, verify bent layout at each major phase of the construction to ensure that the be nt is properly positioned in relation to adjacent bents. 91 91 91 91 91 91 91 91 91 91
Establish the centerline as follows:
will provide.
and bridges.
The Department will furnish at least one bench mark that the Contractor shall preserve, and if necessary, relocate as follows:
Flag and protect in -place survey control monuments and reference points, including Right- of-Way/p roperty line intersections, as follows: 1. Pay for and replace destroyed or disturbed stakes or monuments.
Set other line and grade stakes needed to construct the job, including stakes needed to relocate utilities. Stake the Right- of-Way and maintain throughout the life of the project. Re- stake flattened slopes, minor grade or alignment changes, and other incidentals.
Stake centerline control alignments shown on the Plans or adjusted as described above when the Department needs accurate measurement of quantities for payment. Stake these control alignments as follows:
original and final cross sections.
leveling method.
Prepare and use graphic sketches of super elevation runout on curves on multi- lane roadways and of tie -ins of ramps to mainline on freeways and expressways to help provide positive drainage, adequate super elevation, and a pleasing appearance. Prepare and use similar sketches for street or roadway intersections.
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I.Maintain the Stakes After construction has begun in any segment of the project, maintain the stakes that identify construction statio n numbers and locations as follows: 1.Ensure that stakes are placed at intervals not to exceed 200 ft. (60 m) and use even, 100 ft. (30 m) stations. On asphalt shoulder widening and earth shoulder reconstruction projects use mile post numbers whens tations are not used. Mark and flag stakes so that they are visible to DOT Project personnel in that segment of the project until construction is complete. Projects utilizing GPS controlled fine grading equipment, place stakes at intervals not to exceed 300 ft. (91 m) on English projects and 100 m (310 ft.) on metric projects. Use even, 100 ft. (30 m) or 100 m (310 ft.), stations. 2.During grading activities in fills or cuts over 20 ft . (6 m), extend slope stakes up or down the slopes in intervals of 10 ft . (3 m) or less to achieve an accurate cross section. 3.Denote the offset distance to the construction centerline on the station number stakes, when the statio n number is maintained in a location other than on the construction centerline. On asphalt shoulder widening and earth shoulder reconstruction projects use the offset to the edge of pavement on the stakes. J.Traffic Markings When traffic markings are to be placed by either the Contractor or others, furnish the layout and clean and pre-line the surface to allow the placement of permanent pavement markings on the project. When traffic markings are not included in the project plans, the Department will provide striping plans and/or standard drawings for the Contractor’s use. K.Provide Bridge Construction Layout Provide alignment control, grade control, and calculations to set these controls for bridge construction. For new bridges, the Department will furnish the necessary input data forms for the Department’s Bridge Geometry computer program upon the Contractor’s request. The Department will process the data to help the C ontractor obtain finished deck elevations. Data processing is available only as an alternate service to determine elevations. If this service is elected for use, prepare the input data and the Department will furnish the output data. The following limitations apply: •The Department will not assume liability for the accuracy of either input or output data. •The Department will limit this service to two programs per bridge. •This service is not available for existing bridges that are to be widened. Finished deck elevations for bridgesthat are to be widened will not be furnished. 149.3.06 Quality Acceptance The Engineer’s acceptance of all or any part of the Contractor’s layout shall not relieve the Contractor of responsibility to secure proper dimensions for the completed work. Correct at the Contractor’s expense work incorrectly located due to layout error. 149.3.07 Contractor Warranty and Maintenance General Provisions 101 through 150
149.4Measurement
This item is not measured for payment. 149.4.01 Limits General Provisions 101 through 150 93 93 93 93 93 93 93 93 93 93
149.5Payment
This work is not paid for separately. The costs for performing layout work as described in this specification are included in the bid for the items of work to which the layout is incidental. Any unnecessary work, overruns, costs, etc., resulting from inaccurate data submitted by the Contractor will be deducted from Contractor payments. 149.5.01 Adjustm ents General Provisions 101 through 150 94 94 94 94 94 94 94 94 94 94