X hits on this document





41 / 220

Right-of-Way that was donated or obtained by court order. The Resident Engineer should be aware of the law on this as noted above. Where a question arises on this, the Resident Engineer may request assistance from the Construction Office or other appropriate Divisions.

Resident Engineers should also be aware that Subsections 105.09 and 107.12 of the Specifications require the CONTRACTOR to protect these monuments during construction.

(c) Permanent Bench Marks. Permanent Bench Marks are specified on the

plans for most contracts. Ideally, they will be placed in R. C. Box Culvert bridge wingwalls, or pipe culvert curtain walls when these are poured. permanent bench marks are to be placed at approximately 1½ mile intervals.

headwalls, Generally, However,

when the locations are shown on the plans, the plan locations shall be followed. It responsibility of the Resident Engineer to install these permanent bench marks. metal caps are stocked at the District offices.

is the The

In situations where there is no new concrete work to be done at the location where the bench mark is to be placed, the Resident Engineer should construct a CAST IN PLACE concrete marker in which to place the bench mark cap. This marker should be approximately 6 inches in diameter and extend 2 feet below the ground line. Construction

of the should should

marker should be in such manner as to inhibit the possibility of settlement. It

be placed near the right of way line, preferably near protrude above the ground line not more than 2

a right inches.

of way marker, The location

and and

installation should be such that maintenance operations cases, it may be necessary to drill a hole in an existing stem of the bench mark cap and epoxy the cap in place.

will not concrete

be affected. In some structure to accept the

After the bench marks have been installed, a set of check levels must be run to establish the elevation of each bench mark. The elevation and the location of the bench mark are to be recorded on the form shown in Figure 105-2. The completed form is to be forwarded to the Surveys Division. To determine the log mile on a new location, it is acceptable to use a vehicle odometer to measure the mileage from a point where the log mile is known. In addition, show the Township, Range, and Section in which the bench mark is located. DO NOT STENCIL OR OTHERWISE PERMANENTLY MARK THE METAL CAPS.


In order to comply with National Geodetic Survey requirements for

elevation data, the procedures for establishing elevations of benchmarks set during construction need to follow the procedures for 3-wire leveling, using AHTD SDMS data collection software. This includes turning in the SDMS data files to Surveys Division for checking and processing the data. This is outlined in the Surveys Manual, produced by the Department’s Surveys Division. The current version of this Manual is found on the

AHTD Intranet through the Surveys Division SDMS Collector link. stored as “SurveysManual.zip”.

The manual is

Refer to Subsection 107.03 of this Manual for procedures on preservation of Federal Land Markers and Section corners.

Rev. 11-30-04

Page 100-26

Document info
Document views1120
Page views1120
Page last viewedSun Jan 22 22:51:47 UTC 2017