Calibration and Testing of Survey Equipment
Prior to commencement of survey works, the Chief Surveyor shall ensure that all survey equipment such as Total Stations and Automatic Levels deployed in the project are within the calibration period or duly registered.
Automatic Levels shall undergo peg tests every two weeks to ensure that readings are within allowable errors. Peg test records shall be compiled by the Chief surveyor.
The Chief Surveyor shall ensure that all survey equipment will be recalibrated on or before the expiration of calibration certificates.
Together with the client, the survey group shall schedule a joint inspection or reconnaissance for familiarization of the project site and to check if the survey control points are still undisturbed. All disturbed control points shall be recorded and reported accordingly.
Coordination Meeting of Survey Teams
The Chief Surveyor shall conduct daily coordination meeting (preferably before or after the daily toolbox meeting) to orient the survey teams on their assignments/work area to eliminate confusion and double handling of work items when the field survey has commenced.
Establishment of Horizontal and Vertical Controls
All survey works shall be reference to the existing survey control points within the project site. In cases where additional control points are needed, traverse and leveling surveys shall be done. The surveyor shall ensure that errors accumulated within the surveys are within the allowable tolerances as stated in the DENR Administrative Order 2007 – 29 or the Revised Regulations on Land Surveys (Article 7 Section 28.b Project Primary Control).
Survey control monuments shall have a standard dimension of L20cmxW20cmxH50cm with 30-40cm embedded on the ground. In cases of hard ground, monuments shall be cement putty type with standard dimension of L20cmxW20cm.
The survey group shall ensure that a topographic survey shall be done before the start of earthwork activities.
All visible features will be measured using ground measurement points for every feature that needs to be shot. These points will be spread throughout the project area in sufficient number to fully cover all features and the entire ground, and to ensure accurate computation of the contour lines and elevations. Also, the gathered data shall be the basis for the earthworks (cut and fill) computations.
All man-made structures such as buildings, roads, culverts, drainages, bridges, walkways, etc., within the project, site will also be measured in order to get their ground footprint. All other elements on the ground, such as plantations, trees (with a minimum diameter), rivers, streams, etc. will also be included the measurements.
All survey layouts shall be based on the latest AFC drawings. The Chief Surveyor shall facilitate the distribution of latest Approved for Construction drawings to the survey teams to ensure correctness of survey layouts at the project site.
Horizontal road layouts shall be done at 10 meter interval (straight) and 5 meter interval (curves). Toe and embankment limit shall also be marked at the same interval.
Survey stakes shall be in the form of woods or rebars (preferably 10mm diameter). Elevations shall be marked with the use of masking tapes to determine the required elevations.
Excavations shall be initially marked in the ground using wood stakes. Batter boards shall also be placed (1 to 2 meters offset) if needed to serve as permanent guides for the excavation team. Benching at required slope ratio shall be done.