Feature: A New Age of Construction Automation
Professional Surveyor Magazine - July 2010
Part 2: Process and Partnership Changes
By Terry D. Bennett, PLS, LLS, LPF, LEED AP
In Part 1 of this series (April 2010), I discussed what GPS machine control is and why surveyors, civil engineers, and construction firms around the world are implementing it for use on heavy highway construction and land development projects. I also introduced the building information modeling (BIM) process and explained how a model-centric process helps facilitate GPS machine control by enabling surveyors and civil engineers to easily and quickly provide contractors with the rich data they need to automate construction equipment. In this article, I discuss in detail how adoption of these new technologies and processes may affect your business and recommend several new workflows and procedures that can help increase the odds of your success.
As I mentioned in Part 1 of this series, BIM is an integrated, collaborative process that enables everyone involved in a project—surveyors, engineers, architects, contractors, and clients—to work from a single, digital project model so they can share reliable, coordinated information at every stage of a project lifecycle, from design through construction to operation. In a GPS machine control system, surveyors and civil engineers can transfer a variant of this model directly into the onboard computer of an excavator, grader, or bulldozer, enabling the contractor to shape, grade, erect, or move materials exactly as the designers intended. This type of approach also enables project teams to use limited resources—both human and material—much more efficiently and sustainably.
Availability of a 3D building information model is so valuable to the GPS machine control process that, in many cases, even if a contracting firm receives 2D plans and profiles from a surveyor or engineer, it will still spend valuable time and effort creating additional 3D models for use in its GPS-controlled construction equipment. When I speak with these firms, they invariably say that they would prefer to receive a completed model.
The benefits are simply too great to ignore, as detailed in the following quote from Tim Tometich, GPS division manager, McAninch Corporation
: “Traditional processes of paper plans, stakeout sheets, and grade stakes used to take up to a week to implement. Now with GPS machine control and 3D models from designers, that same size project can take hours. This allows us to reduce fuel consumption, idle time, air pollution including greenhouse gas emissions, and material waste while providing our clients with a more accurate product. We believe that starting from 3D models to drive the construction process is the way of the future.”
Additional overall benefits for surveyors and engineers providing 3D models to construction professionals include the ability to:
Increase productivity and efficiency:
GPS-enabled construction equipment can run all day—and all night—while achieving accurate grades on the first pass. As a result, I have seen first hand and in reports that it is possible for construction teams to:
Overcome labor shortages:
- increase productivity by up to 50 percent,
- reduce guesswork and costly rework by moving dirt right the first time,
- cut redundant survey costs by up to 90 percent,
- increase material use,
- reduce idle time and rework,
- reduce fuel consumption (by 43 percent) and associated green house gas emissions,
- lower overall operating costs, and
- extend the work day.
GPS machine control enables equipment operators with limited experience to routinely complete in one pass work that was previously performed only by seasoned construction professionals (Figure 1
)—often in multiple passes. This capability helps reduce labor requirements and costs, accelerate project completion, reduce the need for stakes, string lines, and grade checkers, empower operators to check grade from the cab, and minimize labor needed for staking as jobs progress.
Achieve impressive return on investment:
According to a recent industry survey, contractors who recently invested in GPS machine control spent a median of $50,000–$74,999 and paid for their systems within 13 to 18 months. In addition, 70 percent of respondents report that GPS machine control increases their opportunities to bid contracts.
Change the Way You Work—and How You Think
With all the advantages listed above, it’s clear that the adoption of GPS machine control technologies and processes brings with it a higher return on investment and new business efficiency. However, because sharing a single data model among many different disciplines can also lead to uncertainty about data ownership and liability, it is important to explore new contractual approaches to project delivery as part of any implementation plan.
To better understand how modernization of heavy construction activities can affect business-level processes, consider the following excerpt from an online article in Constructioneer: “Another stumbling block that UCC [Constructors] overcame was acquiring the machine control data itself. Contracts prevented UCC from receiving the digital files directly from the engineer. But because of the extreme productivity advantages of using the technology, UCC instead took the time to recreate the 3-D files from the engineer’s certified 2-D drawings.”
To successfully implement a GPS machine control construction automation solution, your firm will have to contractually change the way it acquires data. On this level, it is not so much a technology change as one of mindset.
Integrated Project Delivery
Let’s look at part of the quote above: “Contracts prevented UCC from receiving the digital [design] files directly from the engineer.” The BIM-created, intelligent model is as essential to the GPS machine control process as paper plans are to traditional construction staking. Without this model, the construction automation process comes to an immediate halt. Yet, until recently, all of the business processes, contracts, and legal writings addressing liability and risk management focused only on the transfer of a roll of paper plans from the surveyor or engineer to the contractor—with no provision for how to address the alternate methods of delivery associated with construction automation.
Over the past year, industry experts have worked together to develop several new project delivery methods that address licensing and usage rights for the distribution of digital data, such as 3D building information models. Most prominent among these new approaches is integrated project delivery (IPD), a new collaborative practice model that contractually requires the owner, architects, engineers, surveyors, and contractors to share a project’s risks and rewards and work together as a single, integrated team from project outset to completion.
Although not created specifically in response to recent developments in GPS machine control technology, IPD—and its straightforward direction on how to craft legal agreements that address shared data, risk, and liability within an integrated team of professionals—offers tremendous benefit to firms that want to implement such technology. In fact, GPS machine control systems are a perfect example of why contractual agreements within the AEC industry must now include legal provisions for how to share the data model. Other than BIM and sustainability, no other cross-disciplinary subject receives more attention within the AEC industry than IPD. IPD promises to play an important role in the future adoption of GPS machine control.
The UCC Constructors’ quote above also mentioned the impressive productivity gains associated with adopting the BIM process. I would argue that these gains—mostly in time, materials, and fuel—translate directly into an increased ability to design and build more sustainable projects. Virtually all design and construction processes rely on energy, whether it’s electricity to power a desktop computer or fuel to run heavy equipment. Regardless of the type and source, one trend has been consistent over the last 35 years: energy prices have risen steadily. Unless your firm has invested time, money, and effort in learning how to design and construct more efficiently, energy costs now represent a much larger share of your operating expenses than ever before—with no end in sight.
Because the BIM process and its easy integration with powerful analysis software enables you to accurately predict project performance, appearance, and cost before you begin a project, it is the ideal tool for optimizing resource use and minimizing project waste. By combining BIM with GPS machine control, contractors can streamline field operations and greatly improve their ability to achieve finish-level grading on the first pass—saving both time and considerable amounts of fuel.
In addition, today’s large and increasingly complex projects require the harvesting and extraction of large quantities of natural materials, such as gravel, sand, and loam, as well as the production of a wide variety of industrial materials that emit pollutants as by-products of their production process. Using the BIM process and GPS machine control, contractors can grade to millimeter-level accuracy and eliminate virtually all “padding” and its associated costs—both monetary and environmental.
GPS machine control has already revolutionized the construction industry in many regions of the world and will continue to do so in other countries by making it possible for contractors to complete projects faster, within budget, and to a much higher degree of accuracy. In fact, by using GPS machine control technology and the BIM process, contractors can match a design engineer’s specifications to within a millimeter in horizontal position and a centimeter in elevation.
Because this approach enables the contractor to incorporate design changes in real time, idle time is dramatically reduced and construction equipment can operate 24 hours a day—increasing efficiency and profitability. Wireless live links between the site computer and the onboard computer in a bulldozer, grader, or excavator increase that efficiency even more. The construction manager can receive up-to-the-minute progress reports, download design changes sent by the surveyor or engineer, and blend the two seamlessly right into the cab of the construction equipment—thus avoiding mid-cycle surveys and re-staking.
With all of the recent advances in construction automation, it’s no longer a question of whether surveyors, civil engineers, and contractors are going to adopt this new, more efficient—and more profitable—way of completing heavy highway and land development construction projects. It’s only a question of when. Don’t get left in the dirt!
Terry Bennett, PLS, LLS, LPF, LEED AP is senior industry manager for the Civil Engineering & Construction AEC Industry Group at Autodesk.
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