| Construction is All Around Us | | | | Highway Construction Surveying |
| No matter where in the civilized world you go, | | | | The placement and construction of highways is one |
| construction crews are bound to follow-or else they | | | | area where the involvement of a construction |
| have already been there. Buildings, highways, bridges, | | | | surveyor is especially valuable. First, the existing terrain |
| pipe or high-tension lines, plus countless other | | | | is surveyed. Areas are noted where dirt must be |
| manmade structures, all require construction crews to | | | | excavated, especially to what level and grade. Once |
| create or modify them. And where you find | | | | the material is moved, the surveyor will double-check |
| construction, you will invariably find one or more | | | | that everything matches the plans. One goal is to |
| construction surveyors. | | | | reduce the distance excavated material travels, so |
| Starting Off on the Right Foot | | | | engineers take the surveyor's computations and |
| Before any construction job can proceed, the project | | | | create something called a "mass diagram" to figure out |
| area must be surveyed. The drawings created by the | | | | optimal relocation sites. In other words, they will take |
| engineering team must be oriented to the actual lie of | | | | dirt from Spot A that requires reduction and move it to |
| the land. Measurements of the building site are taken | | | | Spot B that requires build-up. In the old days, wooden |
| using surveying equipment, which are then compared | | | | stakes were driven into the ground to mark road |
| to the set of master blueprints. These initial | | | | edges in the highway alignment stage, but the |
| measurements will serve as the basis for all events | | | | accuracy and widespread usage of GPS has |
| that take place throughout the construction process. | | | | eliminated this laborious process. |
| The Total Station-The Surveyor's Top Tool | | | | Building Construction Surveying |
| Prior to the electronic age, surveyors used something | | | | A construction surveyor controls the location of |
| called a transit to help mark locations and perform | | | | everything from foundation lines to footings to ancillary |
| other surveying-type tasks, such as defining angles. | | | | items such as sidewalks and driveways. Using a total |
| The total station is the modern update of that vital tool, | | | | station and observed GPS data in a manner similar to |
| and it is the prime piece of equipment in any | | | | highway construction, every spot and corner is noted |
| construction surveyor's bag of tricks. Sitting on a tripod, | | | | in the field and then compared to the master plan. One |
| the total station uses trigonometry, triangulation, and | | | | specialized job for the construction engineer is to |
| coordinates (x-y-z in a three-dimensional plane) to | | | | ascertain the proper placement of anchor bolts on |
| measure angles and distances in the field. Points are | | | | structural steel and pre-cast concrete. Because of the |
| marked and noted in the total station's software, and | | | | nature of the item-these bolts, after all, are responsible |
| all data can be downloaded to any number of | | | | for holding the building components together-the exact |
| computing-type devices in order to create a map, | | | | placement of each bolt is critical to structural integrity. |
| modify an existing map, or simply confirm that map | | | | Since there is such a wide variety of design in buildings, |
| data are correct. These days, GPS data are also | | | | anchor bolts can be placed anywhere within or without |
| incorporated into the total station's computing ability. In | | | | the building's footprint. They may not fall in a straight |
| outdoor locations where sky visibility is adequate-urban | | | | line, so a construction surveyor must be ever vigilant to |
| canyons or heavy tree canopy conditions can be | | | | follow exactly the architectural and engineering plans |
| problematic-it is not unusual for a construction surveyor | | | | when marking anchor bolt locations on individual |
| to achieve sub-centimeter accuracy. | | | | structural components. |