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ASC Proceedings of the 24th Annual Conference
California Polytechnic State University - San Luis Obispo, California
April  1988              pp 54-57

 

METHODS IMPROVEMENT UTILIZING VIDEO

 

H. Stephan Egger
University of Northern Iowa
Cedar Falls, Iowa

 

On the construction jobsite, video technology can be utilized in facilitating method improvement. Jobsite operations, conditions, and events can be documented, examined, and modified if desired. Analyses ranging from crane movement to craft productivity to sub-contractor clean-up can be monitored. Safety and training can also be addressed or emphasized. Video, with its instant replay capability, allows for immediate review and analysis of field findings, formulation of recommendations and an implementation strategy. Of major significance is the irrefutable record that is established. The merits of method improvement via video were tested in various field operation, some of which included: tilt-up, precast, cast-in-place, and metal stud installation. Some of the recommendations resulting from studies of these operations narrowed in on better usage of manpower and equipment, material layout and handling, pre-planning, operation procedures, and jobsite safety.

 

 

INTRODUCTION

 

Video technology is a medium capable of being used beneficially for method improvement in construc­tion. Videotaping allows for the capture of operations, procedures, and conditions on the construction jobsite. Items ranging from safety to training to documentation of jobsite events, such as date and time, weather conditions, workers' designated tasks, subcontractors' progress, and subcontractor clean-up can easily be recorded. Once recorded, the information is a historical record which cannot be easily refuted.

 

As with super 8 mm time-lapse photography, video also has the capabilities of examining individual and/or group activities, relationships of ongoing activities, and otherwise unapparent or unnoticed conditions. Additionally, the workers and supervisors usually enjoy watching themselves and, if properly involved, will become constructive critics and will help support methods to increase productivity. A major advantage of video recording over the time-lapse system (super 8 mm film) is the capability of instant playback, thus affording

immediate review and analysis, the formulation of findings and immediate implementation of recommendations. Super 8 mm film development involves an inconsistent turnaround time due to mailing and handling which doesn't allow for immediate analysis, much less implementation of recommendations.

 

The versatility of video leaves only the imagi­nation open for discovery of ways of implementing methods improvement. Presently, there are player/ monitoring systems which can be handled with one hand, are portable, and present the potential to be used for weekly tool box meetings. Also, there are cameras available with built-in time-lapse features.

 

This past summer, I was a consultant to Hensel Phelps, Inc. The jobsite was a 43.7 million dollar state prison and consisted of approximately 650 acres of constant construction activity, involving just about every conceivable type of construction. Without the use of video,, the diversity and rapidity of events occurring in the field would have made their study difficult if not impossible. I was afforded the opportunity to analyze settings such as concrete pours, tilt-up, precast, metal studs and drywall operations. Management in the field and office, and also the individual workers, were supportive of methods improvement. Phelps allowed open access to office and field data as well as open availability of managers and individual workers, which greatly supported efforts to proceed with productivity analyses. In a consultant capacity, this strong support and commitment from a company is a necessary ingredient for utilization of method improvement on the jobsite. Phelps makes a strong commitment to its people, clients, and projects which is highly conducive to success on the jobsite as well as in the marketplace.

 

 

EQUIPMENT AND PROCEDURE

 

In the actual productivity analysis at the Corcoran site, two video cameras were utilized. The two systems afforded a complete coverage of activities on the jobsite. One camera (1/2" VHS) was placed in a stationary location (typically on an adjacent building or job trailer) to observe total activity for a specific operation over a 5-6 hour period. The second video camera, which was portable, was used intermittently to record operations from various angles and/or specific segments. An 8 mm Sony system was selected because of its smaller size, in comparison to 1/2" VHS and the fact that 8 mm tapes are approximately one half the size. This offered needed convenience on the jobsite.

 

The basic strategy in analyzing an operation is to work closely with the managerial staff (office and field), the crew(s), and the individual craft person. It is important to maintain an open line of communication from the pre-planning phase through to the examination of the completion phase. Using two camera systems to record gave me flexibility to identify and document significant steps in an operation and, if necessary, to direct communication with individual personnel about specific steps. This observation capability allows for site data collection which complements the information being collected on the video tape. Upon completion of videoing the operation, all the data is examined, always more than once. The fast forward and pause modes of the video player present clear and accurate evidence as for the analysis of an operation. The next step involves editing the 5-6 hours of taping and dubbing a 5-10 minute tape which is presented to small brainstorming sessions consisting of management and field personnel involved in the actual operation. Lasting approximately half an hour a session again affords a two-way line of communication, exchange, and confirmation of suggestions and/or recommendations for improvement. More importantly, by involving all- parties in the operation, a commitment is made to supporting method improvement for an operation.

 

ANALYSIS OF THE PLACEMENT OF TILT-UP CONCRETE PANELS FOR BUILDING 306 ABCX AT THE CALIFORNIA STATE PRISON - CORCORAN

 

Overall, the placement of the tilt-up concrete slabs on Building 306 proceeded with minimal difficulty, considering it was a new endeavor attempted by Hensel Phelps. Time utilization

of manpower and equipment (table one) highlights the importance of tilt-up panel layout on the ground slab. Layout was shown to affect time usage of the crane (1 hr. 45 min.) plus the travel of individual workers. The column dealing with placement and adjustment demonstrated that time spent per panel varied considerable and that the procedure was a major consumer of time (3 hrs. 20 min.). These inconsistencies were primarily due to inadequacy of the adjusting plates, manpower organization, the drilling of holes to hold the bracing in the ground slab, the spacer, and supporting apparatus. However, through the use of videotaping, personal observations, and the small group brainstorming session (after the placement of the slabs), the following specific items and/or operations were identified for improvement.

1)      To facilitate the layout and placement of the tilt-up panels, a recommendation was made to utilize a model (paper or card­

2)      board) of the ground slab and individual tilt-up panels to preplan and portray the actual operation from casting to place­ment. This would not only facilitate layout and placement, but increase communication throughout the operation.

3)      A suggestion was made to consider the possible utilization of a casting slab, slabs of buildings surrounding 306, and/or the concept of stacking panels to facilitate a more adequate set-up.

4)      To decrease the amount of time spent on drilling the holes for the supporting braces, the purchase of an air drill was recommended. Also, the compressor that would be utilized for the air gun would aid in the cleaning of the pick points. An alternative to the purchase of an air drill was the placement of dowel inserts in the ground slab at appropriate loca­tions. However, the three different kinds of bracing brackets currently utilized at the tilt-up work area would produce problems with the use of dowel inserts.

5)      There was group consensus in the recom­mended usage of grout pads over teflon adjusting plates. There was a general dislike toward teflon plates because of their tendency to shift during panel placement and adjustment.

6)      Appropriate rigging to facilitate the placement and adjustment of individual tilt-up panels was also discussed. The four sheaves and cables for the crane were found to consist of varying sizes at the time of the lifting operation. Then, upon using straight cables, the layout of the pick points didn't line up with the spreader bar which made pick-up difficult. This also could hav'e resulted in safety problems and damage to the tilt-up panels. In one instance, four pick points were utilized instead of the designated eight which posed a question in regard to safety and damage to the panel and/or ground slab.

7)      Workers suggested that tasks be assigned to individuals to aid in accomplishing designated segments of the operation. Example: Members of the team, at the ends of the panel, calling out specific orders during the placement and adjustment phase.

8)      There was also consensus of the brainstorm­ing group in regard to the size of the work team for this operation. Recommended was one operator, one oiler, two ironworkers, two carpenters, one laborer, and one supervisor.

9)      Another suggestion was made to increase the size of the weld angles to 3 x 6 to facil­itate the placement location of tilt-up panels and securely weld the angles in place.

10)  The importance of accurately locating plumbing and aligning the tilt-up panel before the rigging is released and/or removed was stressed. The lack of accurately locating and adjusting tilt-up panels produced major problems with later placed panels. In fact, at a later date, the crane had to be brought back in to readjust panels.

 

TIME UTILIZATION IN PARTIAL PLACEMENT OF TILT-UP CONCRETE PANELS - 306 ABCX TIME SPAN = APPROXIMATELY 6-1/2 HOURS

 

 

SUMMARY

 

Video does present an excellent medium for handling method improvement on the construction jobsite. Capabilities include documenting jobsite operations, procedures, and conditions. It also has potential for training and safety. The versatility of video, plus its instant replay, combine to make it an excellent tool for method improvement. In applications, it facilitated the identification of problem areas and conditions which could be improved. Recommendations from the analysis of the video tapes, site observation, and small group discussions combined to help formulate ideas for method improvement.