Using RTK for Construction Staking

Real-time construction staking, like real-time surveying, can be a much better process than using other methods if it is performed by a professional land surveyor. Having to process data from a survey conducted with older technology can take up valuable time and resources that don’t need to be utilized anymore. Using Real Time Kinematic (RTK) for construction staking is effective, and allows for real-time information and positioning so that the surveys and stake placement can be as accurate as conventional land surveying and done in less time. RTK basically focuses on utilizing actual information at the time of survey based on GPS information, rather than analyzing and processing the data after a survey.

Why use RTK?

RTK for construction staking is becoming increasingly popular among surveyors because it allows for improved accuracy, faster survey times and quicker return to the builder for continuation of the building project in question. Construction staking is a critical part of the building process because it helps to identify everything from land grades and utilities to positioning for corners, structure walls, and other parts of the building as per the site survey. Having a building constructed in the exact right place on a parcel of land is critical, which is where construction staking comes in handy.

There are many professional surveyors already using RTK for construction staking, and it is likely only a matter of time before all survey professionals rely on this method for their surveying needs. As technology evolves in our industry, the tools and methods we use evolve with it, making the survey process more efficient, more accurate and less time-consuming. RTK surveying tools and processes allow for fewer professionals to do more work with better results.

How RTK Works

In practice, RTK systems can currently be integrated with conventional or robotic total stations to allow the surveyor even more options during construction staking. RTK systems use a single base station receiver and a number of mobile units. The base station re-broadcasts the phase of the carrier that it measured, and the mobile units compare their own phase measurements with the ones received from the base station. There are several ways to transmit a correction signal from base station to mobile station. The most popular way to achieve real-time, low-cost signal transmission is to use a radio modem, typically in the UHF band. In most countries, certain frequencies are allocated specifically for RTK purposes. Most land survey equipment has a built-in UHF band radio modem as a standard option.

This process allows the units to calculate their relative position within millimeters, although their absolute position is accurate only to the same accuracy as the position of the base station. The typical nominal accuracy for these dual-frequency systems is 1 centimeter ± 2 parts-per-million (ppm) horizontally and 2 centimeters ± 2 ppm vertically.
Using RTK for construction staking does rely on the availability and accuracy of GPS satellites and receivers. Overhead coverage such as trees and buildings can interfere with these signals, which is something that professional surveyors have to check for before they can get started on the surveying process. However, there are usually software programs included with surveying equipment that make it easy to predict satellite locations and availability to ensure that RTK staking can be used at a particular site during a particular time or day.

Real-time staking saves time, energy, and manpower resources in the professional surveying world, allowing more work to get done with accurate results and fewer man hours used. During a time when surveyors are in short supply, this is an asset that many cannot afford to live without.