Bridging the Divide
by Michael M. Slusarski , PE
September 1, 2006
A Volvo 726B grader equipped with GPS grades the site using a data model created by the author through collaboration with the project owner’s engineer.
Civil engineering/survey firms explore a new level of collaboration for GPS machine control projects.
As an increasing number of contractors seek to reap the benefits of GPS guidance and machine control, the hurdles and obstacles that they face in implementing this technology are becoming more well known. These hurdles are likely to impact contractors’ businesses and challenge their traditional roles and responsibilities, processes and relationships. However, obstacles to the use of GPS machine control are not limited to the contractor; engineers and civil/survey firms also face challenges with this technology’s adoption. This article highlights the issues facing the sitework engineer and surveyor. (For an overview of the challenges facing the contractor, see “A New and Different Way,” Site Prep Summer 2006.) Engineers and surveyors must learn how to address the challenges they face and collaborate with contractors using GPS technology.
Typical Design to Construction Cycle
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First, a review of the traditional information exchange during a project cycle is necessary. Reviewing this cycle brings to light a number of the changes that civil/survey firms are likely to encounter when contractors implement GPS technology on the jobsite.
Figure 1: This illustrates the civil/survey barriers within a common construction project and the poor information flow that results.
The typical information exchange for a design-bid-build project is illustrated in Figure 1 on page 23. In this scenario, it is assumed that the civil/survey firm is responsible for a 100% complete design prior to construction, and that the design engineer will not be representing the project owner for the administration of the contract.
When working in this traditional relationship, the engineer and contractor each take ownership of a specific portion of the project cycle. There is little to marginal overlap outside of their focus areas. The civil/survey firm focuses primarily on the front end of the project. It may be contracted by the project owner for feasibility analysis, conceptual plans, preliminary approvals, full engineering design (grading, utilities, etc.), creation of construction plans and approvals, as well as required surveying activities for the project (boundary and topographic survey, ALTA survey, floodplain identification, construction surveying, etc.).
The engineer/surveyor’s communication with contractors during this portion of the project is usually minimal, since the project has yet to be awarded to a contractor through the bidding process. Upon approval of the construction plans, contractors bid on the specified work, which is then typically awarded to the capable low-bid contractor. As illustrated in the diagram, after the civil/survey firm completes its work according to the contract with the project owner, the engineer/surveyor hands over the information (and ownership of that portion of the project cycle) to the contractor. The contractor then performs the work per the project specifications.
While the engineers need to be accessible for questioning during the construction of the project (through RFIs and phone calls made by the contractor), their involvement is minimal. Information flow between the civil/survey and contracting parties may be cumbersome and possibly channeled through the project owner with the aim of controlling engineering/surveying billable hours. Engineering revisions are often communicated through a revised set of construction plans literally showing up at the contractor’s doorstep--sometimes with little or no description of the changes. This process may vary depending on whether the project owner has contracted the engineering/survey firm for the inspection (QA/QC) of the project and the administration of the contract.
At best, the relationship between the engineer and the contractor is no more than an arm’s length acquaintance where information is exchanged on an as-needed-and-requested basis. At worst, the relationship becomes adversarial in nature. This may happen when the engineer functions as a check and balance to the contractor, especially when the civil/survey firm is contracted for inspection and contract administration. Whatever the relationship’s ultimate outcome, it is rare for the engineering firm and the contractor to look beyond their traditional roles and work together with a collaborative, end-to-end project focus. This lack of cooperation results in the common divide between the engineering/design and construction phases of a project.
Collaborative Exchange of Information
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When contractors begin utilizing GPS guidance for jobsite construction, they must bridge the traditional gap by establishing an effective and proactive relationship with the civil/survey firm. The strength of this relationship affects the ultimate execution of the project. A diagram illustrating effective collaboration is shown to the right in Figure 2.
Figure 2. Using GPS technology as a catalyst, civil/survey firms who adjust their business operation benefit from improved communication with contractors and better project execution/profitability.
In this scenario, while the contractor may not be wholly involved in the design phase of the project, once the construction contract is awarded, the civil/survey firm and contractor collaborate in a partnership. Information flows more freely and, as a result, many costly problems are addressed prior to construction. Design revisions are effectively communicated and implemented, project timelines are decreased and project costs are reduced.
Obstacles to Facilitating GPS Use
A Caterpillar 615C scraper moves clay spoil from a stockpile to a nearby building pad location. Placement of the spoil is performed according to a construction DTM created by the author.
Design Applications
Civil/survey firms typically limit the number of design applications used in the design and survey process in order to leverage economies of scale and knowledge. Exceptions are made for projects with client requirements that specify the applications to be used for design (e.g., the use of Microstation products for many DOT projects).
Benefits to limiting design applications are rooted in efficiency, consistency, productivity and, ultimately, cost. Some of these benefits include the following:
- Company standards: It is much easier to establish a company standard plan set with one CAD application versus many. Common standards for design and plan production are more easily developed, maintained and learned in an environment with limited design/production applications. This optimizes design and production efficiencies (at the lowest total cost).
- Application licensing: A multi-user, enterprise-wide design/plan production application typically costs less than licensing multiple applications with fewer licenses purchased per application.
- Application maintenance/support: Each software application chosen has maintenance and support costs associated with its use. As the number of applications increases, so will the incremental and total cost of multiple maintenance contracts above and beyond that of an enterprise-wide solution.
- Training: It is easier and less costly to train a company’s workforce on one application. More applications require a business to spread its knowledge base more thinly. This may lead to relying more heavily on outside consultants for costly training due to lack of in-house expertise.
When it comes to the tools used in GPS guidance and Digital Terrain Models (DTMs) for site construction, civil/survey firms are faced with a few problems. At the root of the problems is the existence of multiple vendors for GPS guidance technology and the numerous applications that are available to translate and import information to the field. To transfer information, civil/survey firms may simply provide a surface electronic file and plan layout to the contractors, who will then use their own software applications to perform any information manipulation needed followed by importing it into the machines for construction. If an engineering firm decides to get more involved with data conversion from design in the office to construction in the field, it may be necessary to acquire various software products that address the vendor-specific GPS platforms used by different contractors. But the greater the number of applications that an engineering firm acquires to facilitate the effective use of GPS technology, the greater the cost will be in terms of establishing company standards, software licensing, maintenance, training and potential loss in productivity.
DTM Experience
There are many seasoned engineers who can produce approvable 2D plans that are excellent for construction staking. There are fewer engineers, however, who have field experience regarding the actual construction of the designs they create and can translate their design to a 3D model used for construction. DTMs require design engineers to be more in tune with the actual implementation of their design.
Moreover, DTMs can incorporate project enhancing design features that may otherwise be avoided. For example, the incorporation of superelevated roadway curves (banked turns) are sometimes avoided due to the complexity of implementing in the field. However, with a superelevated turn incorporated into a DTM, the curve with a crown transition can be constructed by the grader operator as easily as a road with a normal crown. In addition, a design feature that was once difficult and tedious for the surveyor to stake is now easily constructed through an effectively developed DTM. Engineers who have insight with regards to the capabilities and limitations of GPS technology will be more inclined to adjust their design style to incorporate complex features into their work. This allows them to develop an improved design for the project owners (and will likely save them money in the long run).
So what is the holdup? The engineer has put together a wonderful set of construction plans, so the data model can be released to the contractor for construction, right? Not so fast! A jobsite is almost NEVER ready for construction directly from a DTM created from an approved set of 2D construction plans. The exception is when a site is designed in 3D with the intent to build using GPS and DTMs. To be ready for construction, the DTM must reflect the ultimate build state of a site with exacting precision--before the contractor loads it into GPS equipment. This may even require the development of an intermediate construction DTM per the contractor’s preference that includes construction features such as building hold downs, stripping regions or road subgrade elevations.
Complicating matters further is the fact that a number of excellent engineers lack proficiency at CAD applications and rely on CAD technicians for designing and creating construction plans. These engineers are at a serious disadvantage for successful DTM development. Two-dimensional design, which many engineers are accustomed to, is acceptable for construction staking but contains inherent information gaps such as hand-drawn contours, intersection grades, spot elevations and swale details. When it comes to 3D design, more detail is required to develop a robust DTM for earthwork analysis and construction through hands-on use of CAD design applications and DTM building tools.
Business Model
As contractors make organizational changes to accommodate the implementation of GPS technology, civil/survey firms must also acknowledge the changes such a step will have on their operation. The engineer’s situation is every bit as complicated as the contractor’s. It is fraught with issues of organizational change and potential conflict of interest.
On one hand, it makes sense to perform design in 3D for the overall benefit of the project. The design is vetted to a greater degree, earthwork can be more effectively analyzed and 3D designs can be implemented more easily in the field. On the other hand, performing design to facilitate the contractor’s use of GPS forces the engineering firm to resolve some tough issues, including:
- Market: Is there a market for facilitating the use of GPS by providing DTMs?
- Education: How can a civil/survey firm become educated on GPS vendors that provide guidance solutions and obtain an understanding of the tools and equipment contractors are utilizing?
- Contracts: Construction DTM building is outside of the scope of performing basic design and creating approved plan sets that most civil/survey firms are normally contracted to do. Who is going to pay for the additional construction services? Contractors? Project owners?
- Loss of revenue/conflict of interest: There is a potential loss in surveying revenue. A civil/survey firm may be operating multiple field crews that are assigned to construction staking. Is the contractor becoming a threat to the firm’s livelihood? Will facilitating the use of GPS ultimately result in the downsizing of the survey department?
- Human resources: Locating engineers and technicians with the skill set of civil engineering design, proficiency with design tools, knowledge of construction methods, and proficiency with collaborating with project owners and contractors may be difficult. How can this competency be developed?
- Liability: How will a civil/survey firm protect itself from the liability of potential misuse of information that is provided to a contractor for construction using GPS guidance?
The Bottom Line
A GPS-equipped Caterpillar D6 track-type tractor grades the foundation subgrade for a future ice arena. Frequent and proactive communication between the author and the project engineer was required to incorporate design changes into the DTM.
Adapting to the construction world powered by 3D modeling and the use of GPS guidance and machine control may be a very difficult and painful road for many civil/survey firms. The fibers of the civil/survey business will be questioned, rethought and reworked. The extent of the change will be a business decision driven by how they will choose to serve their customers’ business interests in the future. Some may elect to do little or nothing to facilitate a contractor’s use of GPS guidance. In doing so, they will be avoiding the work required for necessary changes to their business while hedging against the future loss of construction staking dollars.
Other civil/survey firms may see the use of GPS guidance and machine control as a true opportunity to deliver added value to their customers by reducing project cycle times and avoiding cost through a precision designed and built project. These firms may elect to establish their own “GPS Special Operations” divisions that focus on the translation of design information to the field in an effort to bridge the divide between the design and construction phases of a project. The most progressive “GPS Special Operations” departments will be staffed by highly trained and experienced individuals. These individuals will understand the tools utilized for design and plan production as well as the tools and methods required to produce construction DTMs for contractors using different GPS platforms. “GPS Special Operations” staff will also be knowledgeable of construction practices and will be able to effectively communicate with contractors in the development and implementation of construction DTMs.
The range of a civil/survey firm’s investment in tools, training, business change, etc. will range from minimal to substantial. Those firms reluctant to adapt to a contractor’s use of GPS technology will not need to invest much. However, those that seek to leverage the contractor’s use of GPS guidance by setting up their own operations unit will expend sizable amounts of time and money. Regardless of the business decision made by civil/survey firms, the growing use of GPS guidance and machine control will continue to become more mainstream as project owners realize the potential benefit to their bottom line and as a growing number of contractors obtain the technology, seeking to reap their own reward. When it comes to investing in the growing world of GPS guidance and machine control, civil/survey firms must make their decisions carefully. Choosing to do nothing may be the most costly decision they could ever make.
Michael M. Slusarski , PE
mms@slusarski.com
Michael M. Slusarski is a registered professional engineer in
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