157.1General Description
This work includes constructing, maintaining, and removing (when specified by the Engineer) survey aids required at the locations shown on the plans or modified p lans, or at locations designated by the Engineer. Survey aids may be required when line and distance control for excavation, embankment, and/or bridges require triangulation. This work also i ncludes disposing of survey aids, unless the Engineer directs to leave the aids in place. 157.1.01 Definitions General Provisions 101 through 150. 157.1.02 Related References A.Standard Specifications General Provisions 101 through 150. B.Referenced Documents TT-E543 TT-529A 157.1.03 Submittals General Provisions 101 through 150.
157.2Materials
Comply with the following survey aid requirements: A.General The materials used to construct these expendable items do not require pre-inspection or sampling and testing.Replace, repair, or strengthen defective, worn, deteriorated, corroded, or unsatisfactory materials according toSubsection 157.3.07, Contractor Warranty and Maintenance. B.Timber a nd Piles Timber and piles may be untreated; however, all piles shall be peeled. Timber may be of any commercial grad e and species. For triangulation stations, ensure that the center pile for the instrument mounting has a minimum diameter of 1 ft.(300 mm) at a distance of 4 ft. (1.2 m) from the butt . The minimum diameter of other piles in the station shall b e in. (250 mm). Use piles for survey targets that conform to the requirements of the Specifications. The butt diameter for timberwalkway piles shall be at least 8 in . (200 mm). Use piles that will maintain safe walkways for the duration o f the project. C.Plywood Use marine- type plywood for survey targets that is 0.75 in. (19 mm) thick. Paint the plywood with coats that meet the requirements of the Federal Specification noted: Apply an undercoat to all surfaces and edges (TT -E543); second and third coats—apply to all surfaces and edges (TT-E 529A, color number 27875); fourth and fifth coats —apply to colored areas (TT -529A, color number 21105). 116 116 116 116 116 116 116 116 116 116
D.Sheet Metal Caps Use galvanized sheet metal caps for pile heads, galvanized large- headed roofing nails to attach the caps, and galvanized cable to wrap the pile clusters. E.Other Hardware for Connections Use bolts, nuts, washers, etc. of any commercial grade. They do not need to be galvanized. 157.2.01 Delivery, Storage, and Handling General Provisions 101 through 150.
157.3Construction Requirements
General Provisions 101 through 150. 157.3.01 Personnel General Provisions 101 through 150. 157.3.02 Equipment General Provisions 101 through 150. 157.3.03 Preparation General Provisions 101 through 150. 157.3.04 Fabrication General Provisions 101 through 150. 157.3.05 Construction A.Location of Base Lines, Triangulation Stations, and Survey Targets Possible locations of base lines, triangulation stations, and survey targets are shown on the plans. Timber walkways are included as a bid item, but their locations may not be shown on the plans. Actual and final locations of survey aids are based upon Contractors’ own procedures and equipment methods. The Contractor and the Engineer must agree on the most effective means to control the line and distance during construction. At the Preconstruction Conference, discuss with the Subcontractors the plan of operation forreaching this consensus. After the conference, the plans will be modified to show the locations of base lines and the number and locati on s o f triangulation stations and survey targets. Timber walkway locations may not be shown on the modified plans. After receiving the modified plans, make survey aids construction the first operation, including the installation o f ti mber walkways if needed to provide access. B.Location of Survey Points After the Contractor constructs survey aids, the Engineer places instrument mountings and performs field checks and office calculations necessary to provide the location of the survey points. Even though electronic data methods are used to calculate the point locations, the Engineer may not be able to designate survey point locations immediately. Time Charges will not be suspended during this period. C.Clearing and Grubbing The Engineer must be satisfied with the method and the location of all clearing and grubbing necessary for survey aid construction as a part of this work. Dispose of removed materials as directed by the Engineer. D.Framing Perform all framing and construct survey aids according to the Plan details, unless the Engineer permitsalternate details. 117 117 117 117 117 117 117 117 117 117
Drive pile clusters into the underlying firm material to provide instrument mountings. Ensure that these mountings are steady enough to use during wind and wave conditions.
Drive the piling into the firm material to provide and maintain accuracy of the targets under weather and construction conditions specific to the project area.
Drive piling deep enough to provide stability under weather and construction conditions specific to the project area. Walkways may be required to provide access to triangulation stations, to provide access to boats located at the edge of marsh or swamp areas at low water or low tide periods, or for other purposes as designated on the plans or by the Engineer. Alternate designs will be considered if they have equal strength, width, and safety.
Regardless of elevations stated or implied on the Plans or in the Contract, the Engineer can determine how high to construct the survey aids. Construct items above the extreme high- tide mark. The Engineer may require triangulation stations used initially for roadway item control to be built higher. These higher stations may be used in bridge control that may be in the initial or subsequent Contracts. Constructing railing ladders and other vertical means of access are considered incidental to constructing survey aids. 157.3.06 Quality Acceptance General Provisions 101 through 150. 157.3.07 Co ntractor Warranty and Maintenance Maintain the survey aids as follows:
material at the Engineer’s request. Such maintenance is incidental to survey aid construction.
perform accurately.
maintenance required to leave the aid in serviceable use for the future Work. The Engineer must approve of the maintenance. The additional maintenance is considered incidental to survey aid construction. The subsequent Contractor’s maintenance period will conclude when the survey aids no longer are needed for the duration of the Contract. The subsequent Contractor shall maintain the survey aids to the Engineer’s satisfaction needed for Work, as provided in Subsection 105.05, Cooperation by Contractor as incidental to the work. When the aids no longer are needed the Engineer will advise the responsible Contractor. The Contractor who used the aids last shall r emove and dispose of the material to the Engineer’s satisfaction. Removal and disposal is incidental to the work. 118 118 118 118 118 118 118 118 118 118
157.4Measurement
This work is measured for payment in the units shown in Subsection 157.5, Payment , for accepted triangulation stations, survey targets, and timber walkways. Walkway measurements are horizontal and along center lines. No separate measurements for payment are made to maintain, remove, or dispose of survey aids or to provide material, labor, or equipment required of a subsequent Contractor who does not originally construct the aids. All costs incidental to the work shall be included in other Contract Items. 157.4.01 Limits General Provisions 101 through 150.
157.5Payment
This work is paid for at the Contract Price per unit of measurement, complete in place, and when maintained and removed as directed. These payments are full compensation for costs, direct and indirect, of complying with the requirements of this Specification. Payment will be made under: Item No. 157 Triangulation station Per each Item No. 157 Survey target Per each Item No. 157 Timber walkway Per linear foot (meter) 157.5.01 Adjustments General Provisions 101 through 150. 119 119 119 119 119 119 119 119 119 119