Implementing Advanced Construction Layout Technologies Utilizing University/Industry Collaboration – A Case Study

Introduction

One of the hardest decisions construction companies have to make is when to implement a new technology.  If the technology is immature, or if personnel are not convinced of its value, the entire effort often fails.  Conversely, if a company waits too long to adopt a technology, it can fall behind its competitors.  One method of minimizing the risk of adopting a new technology is to do a pilot project on a small scale.  Partnering with an academic institution is a way to minimize the labor involved in the initial learning process. On this project, the building layout process was made significantly more efficient and less costly by using the advanced features of the total station.

Construction educators have realized for several years the benefits of establishing strong collaborative relationships with industry.  These advantages have been well documented (Tener, 1997, Badger, 1999, Powers, Powers, Betz & Aslanian, 1988).  Appropriately, accrediting bodies for construction programs such as the American Council for Construction Education (ACCE) promote these relationships by requiring interaction between industry partners and educators (Hynds & Smith, 2001). Many professional educators feel that these partnerships are critical if construction education is to remain relevant to students, industry and to the nation at large. 

Although there are myriad examples of collaborative efforts that involve partnerships between the construction industry and academia, few examples of small scale collaborations are found in the literature.  Small projects offer some distinct advantages, especially in terms of speed of response. This paper will document a collaboration involving the use of newer surveying technology to enhance the construction layout process.  The specific steps involved in the new process of fully utilizing the total station will be explained in detail.

Initiation of the Relationship with the Constructor

One of the goals of the authors’ academic unit is to produce research or outreach that is relevant and meaningful to the construction industry.  To that end, a three member advisory committee of practitioners was formed to promulgate advice and ideas.

One of the first ideas proposed by the group was a study to determine if and how technology can be utilized to increase the productivity of construction layout. Specifically, can layout efficiency be increased when a constructor develops digital drawings exclusively dedicated to construction layout and utilizes this information in conjunction with advanced features of the total station?  The committee member proposing the study was aware of an upcoming project staffed with a superintendent who was interested in improving the efficiency of construction layout.  After some discussion, the superintendent and the construction company agreed to be a participant in the case study.

General Description of Project and Personnel

The project began in May 2002. The project includes a 12,945 square-foot renovation of an existing courthouse (Figure 1) and construction of a new 19,442 square-foot adjacent expansion. The estimated cost of the project is $3.3 million with renovations, and the expected construction duration is 10 months.

Description of Construction Layout Requirements and Procedures

At an initial meeting, the superintendent described the way he wanted the layout work done.  Points such as corners of strip footings, mid and intersection points of footing edges, and corners of columns must always be identified.  The superintendent used a felt tip pen to indicate these locations on the foundation drawings (Figure 2).  To minimize confusion, each point was given a unique label (not shown).  Later, a coordinate system was established and related coordinate values for each point were calculated.

In addition to the points shown on Figure 3, the superintendent explained that he needed certain reference and control points, to check and control the layout work. These points were also identified on the foundation drawings.

The project manager explained that most of the information required to do the building layout had already been created in digital format, either by the architect or the engineer.  He described the frustration he frequently encountered when trying to obtain this information. He explained that architects and engineers are generally reluctant to share the digital information with constructors.

The project manager further explained that he felt the ideal situation for the constructor is one where the contractor owns all the digital information.  Since this was not the case for the Courthouse, the project manager felt that the contractor should at least own the digital layout drawings.  Although there would be some obvious duplication of effort, he felt there would be considerable benefit in a system where the contractor created digital layout drawings that would contain only layout information and not extraneous details.

As part of the academic contribution to the project, the authors agreed to develop the digital layout drawings for the constructor. A set of the architectural and structural engineering drawings were obtained, and the information needed by the superintendent was recorded.  The authors were now ready to develop the digital layout drawings.

Developing Digital Construction Layout Drawings

The next logical step in the process required the authors to develop a complete understanding of the equipment the superintendent planned to use to layout the building.  The superintendent had given considerable thought to the problem, and proposed using the contractor’s total station in conjunction with their data collector.  After referring to various manuals, AutoCAD 2000 was chosen for the software to develop the layout drawings (Holloway & Lukesh, 1994).  Another software, Survey-Link, which is able to transform the layout data information into a format which can be read directly by the data collector, served as a bridge from AutoCAD drawings to the data collector. One of the more time consuming aspects was to determine the exact format required to export the data from AutoCAD to the Survey Link software.

Before discussing the creation of the digital drawings, it is important to discuss some of the issues arising from the use of digital information.  The sharing and ownership of digital information is an important and complex issue of great interest to the construction industry (Nasr & AbdulNour, 1997).  The sharing of digital information unquestionably increases potential liabilities for the architect and the engineer, and their reticence to share with the constructor is understandable.  Because the digital information required to develop the layout drawings has already been assembled by the engineer and the architect, it seems redundant for the constructor to create yet another digital blueprint.  However, as mentioned previously, the project manager historically had been very frustrated in his efforts to obtain this information, and felt that developing and retaining ownership of this information was an important aspect of the project. 

The development of the digital layout drawings yielded an unexpected benefit.  Prior to this project, the constructor had never developed a set of digital drawings specifically dedicated to layout.  As the academic partner gathered the information necessary to begin the AutoCAD drawings, several dimensional discrepancies between the structural and architectural drawings became apparent.  Obviously, these issues had to be resolved before the layout drawings could be completed.  According to the superintendent, these types of discrepancies are common on almost all projects.  Discovering these errors so early in the construction process gave the contractor time to resolve the issues without impacting the schedule. 

After the dimensional conflicts were resolved, the construction layout drawings were made using AutoCAD 2000 software.  The drawings were created with the knowledge that data would be exported from AutoCAD into the Survey-Link software.  Since the process is critical to the success of the field layout, and since the process is somewhat complex, a relatively detailed method for constructing the drawing is presented below.

Creating the Building Layout Data File

This exported “TXT” file will now include the information needed by the data collector for the layout. As noted on Figure 3, the first column is the numerical descriptor of the point, and the second and third columns represent the related X and Y coordinates.

Using the Digital Layout Drawings in Conjunction with the Total Station

Once the layout information file had been created, it was downloaded into the Survey-Link software. Although creating, checking and downloading the file into the data collector required about thirty hours of first time effort, the actual field layout is now greatly simplified.

After downloading the data file to the data collector, the superintendent, with the help of a project engineer, laid out the entire foundation in less than one and half days. All points on the foundation were laid out from one instrument set up point. The data collector was connected to the total station with a cable. Each point was laid out by simply turning a pre-programmed angle from a reference point, and directing the other crew member to position the reflecting prism at the correct distance. 

Figures 4, 5, and 6 help describe how a typical five foot square column footing was located.  As previously stated, the Survey-Link software transforms the known Cartesian co-ordinates of point 94 to the polar co-ordinates (angle and distance). Thus, the operator simply turns the angle read from the data collector, and directs the person holding the prism along his line of sight to the correct distance, as read on the total station readout.  Point 96 is then located by exactly the same method.  When two of the four points have been located, the contractor uses a template (Figure 6) to locate the other two points on the foundation.  Each of the more than 300 other layout points were laid out using polar co-ordinates, allowing the layout crew to simply “sweep” the site, using a continuously increasing angle.

Upon completion of the “polar” layout, the superintendent spot checked several points. He did this by measuring the X and Y distances (Cartesian) between several footings with a tape, and comparing those dimensions with those on the drawings. No discrepancies were found.

Post Project Interview

The superintendent and the project manager were interviewed after of the layout phase of the project.  Both were enthusiastic about the collaboration and mentioned several ideas that might merit future collaborations. Both emphasized the importance of the ability of a construction company to identify a problem and to be able to move quickly to resolve it by working with an academic partner.

The project manager and the superintendent were asked to comment on the resources required of the constructor to utilize the advanced features of the total station for future work and collaborations.  They identified three distinct areas.

First, the company would have to find a way to create the digital layout drawings. This activity was the most time intensive part of the courthouse project, and required about 25 hours.  They commented that while the drawings could be outsourced, they would ideally be done by an employee of the construction company.

Second, a person would have to be trained to transfer the digital drawings into a format that could be read by the data recorder.  They felt that this activity would ideally be done by the same person that created the layout drawings.

Last, the field personnel would have to be trained to use the data recorder, and to understand how to layout the building using polar co-ordinates and the data recorder in conjunction with the total station.  The superintendent, having done this work himself on the courthouse project, indicated that this step would require minimal training for a person already familiar with the total station.

Despite the resources required, the superintendent felt that the advantages of using the advanced features of the total station far outweighed the cost of the resources.  He stated that more than 300 points were located in a little more than one day, without a single error.  Both the superintendent and the project manager stated that they planned to use the new system on all future jobs where they felt employees were capable of adapting to the new technology.

Near the conclusion of the interview the superintendent raised an interesting idea. He stated that the most important outcome of the new system on this project was the identification of dimensional discrepancies early in the project.  Catching these errors saved thousands of dollars, and costly delays.  Both the superintendent and the project manager opined that the creation of the layout drawings should become a regular and planned for responsibility of the constructor, and part of the general management of all projects. 

Suggestions for Further Study/Research

On the Courthouse Expansion Building project, only 2-dimensional (2D) building layout was performed with total station and data collector. However, the superintendent and the project manager are interested in exploring 3-dimensional (3D) building layout, meaning a third dimension (elevation) can be incorporated into the layout procedure. Additionally, the superintendent felt there was great potential in utilizing the same technique to lay out of curbs and gutters, a service that is now typically subcontracted.

Conclusion

 This case study was important for three reasons.  The study suggests that small scale industry-academic collaborations can be a productive way for construction departments to interact with industry partners. 

 Second, the use of the advanced features of the total station for construction layout, while requiring some allocation of resources, has potential for accelerating the actual building layout and reducing expensive layout errors.

The third and perhaps most important idea that emerged is the concept that constructors should incorporate the creation of layout drawings into their standard project management process.  Simply going through the process of creating the layout drawings almost insures no discrepancies can occur between the engineering and the architectural drawings.  Given the relatively small investment of resources in creating these drawings, it seems prudent that constructors create these drawings as part of effective project management.

References

Arumala J. O. (2000). The Impact of New Surveying Instruments on the Construction Surveying Course of Study. Journal of Construction Education, Vol. 5, No. 3, 227-243.

Badger W. W. (1999). The Study Advisory Council and the Del E. Webb School of Construction at Arizona State University. Journal of Construction Education. Vol. 4, No. 2, 136-151.

Cheng M. Y. & O’Conner J. T. (1996). Arcsite: Enhanced GIS for Construction Site Layout. Journal of Construction Engineering and Management. Vol. 122, No. 4, 329-336.

Crawford W. G. (1995). Construction Surveying and Layout. Creative Construction Publishing, Inc.

Eiteljorg H. II. (1994). Using a Total Station. CSA Newsletter, Vol. VII. NO. 2.

Holloway R. R. & Lukesh S. S. (1994). The Ustica Excavations – A Total Station, AutoCAD at Work. CSA Newsletter, Vol. VII, No. 2.

Hynds T. & Smith J. (2001). Industry Advisory Councils of Undergraduate Construction Programs: A Comparative Study of Common Practices. ASC Proceedings of the 37th Annual Conference, 239-246.

 Nasr K. J. & AbdulNour B. (1997). An Experience of Industry-University Collaboration Research. 1997 Frontiers in Education Conference Proceedings, IEEE, 317-320.

Omura G. (1999). Mastering AutoCAD 2000., SYBEX Inc.

Powers D. R, Powers M. F., Betz F., & Aslanian B. (1988). Higher Education in Partnership with Industry. San Francisco: Jossey-Bass Publihers.

 Tener R. K. (1997). Industry-University Partnerships for Construction Engineering Education. Journal of Professional Issues in Engineering Education and Practice. Vol. 122, No. 4.

Wolf, P. R. (2002). Surveying and Mapping: History, Current Status, and Future Projections. Journal of Surveying Engineering, Vol. 128, NO. 3.

Wolf. P. R. & Brinker R. C. (1989). Elementary Surveying. Harper & Row, Publishers, New York.

Appendix A – Exporting of Layout Data File with AutoCAD

Appendix A – Exporting of Layout Data File with AutoCAD (cont.)