No, not my age … I passed that a few years ago. I’m referring to the number of articles I have written for POB over the years, including this one.
A Quick RecapMy articles from the past can be separated into a number of distinct categories--including planning, communications, instrument setup and use, calibration, equipment care, mistakes and errors, layout techniques, quick checks, rules of thumb, standard practices--as well as some miscellaneous topics.
One of my favorites was titled “Mistakes and errors from the field” (November 2004) and was based on a questionnaire I sent out to construction layout surveyors as I was working on the 3rd edition of my book, “Construction Surveying and Layout.” Just a few of the common mistakes respondents had listed included writing the wrong elevation on a stake and using that elevation to locate a footing; laying out the mirror image of the structure because of lack of understanding of what the plans are communicating; transposing numbers when measuring distance by chaining; using a foot chain and converting to a metric measurement; not holding the prism rod plumb causing the distance to be wrong; not setting up an electronic instrument exactly over the point and not checking to see if the instrument was still level after using it for an extended period of time; not understanding the potential sources of error in total station measurement; failing to turn equal numbers of direct and reverse angles when turning angles; not leveling the instrument when the vertical angle was measured; not “closing the loop when leveling”; not calibrating the instrument before leveling; and being so concerned about the decimal part of the reading when leveling that we read the wrong foot mark.
In “Long backsight and short foresights” (November 2003), I outlined how having a long backsight and a short foresight is a fundamental principle that should always be followed. It is a principle that affects the size of errors in the sighting and angle measurement process of layout. By having a long backsight and a short foresight, the size of sighting errors can be reduced--which is a goal of any good construction layout surveyor. It sometimes isn’t convenient and may take more effort to provide a long backsight by requiring someone to walk long distances, but the rewards are great by ensuring that errors will be reduced.
In a two-part series on “One-person surveying techniques” (January 2001), I noted that “with the advent of robotic total stations and GPS, one-person surveying is much easier and is becoming a common practice.” However, even without those technologies, one-person surveying is still possible. I related working alone in surveying to working alone as a woodworker. An efficient woodworker figures out what is needed when building a “jig” to do a repetitive task. The jig then acts as a second person in the activity. An example might be to use a shovel with a “D” handle to hold up a level rod as readings are taken. Another might be to use a bungee cord around a tripod and hold a level rod vertically over a bench mark. The article highlighted a number of one-person techniques in layout that could be used when working alone or when working with a laborer or carpenter.
Another favorite of mine was my March 2008 article on “The one-minute, one-person peg test.” In this piece, I explained how a peg-test area could be set up using a yardstick, a piece of level rod or a section of carpenter’s tape positioned at exactly the same elevation on two stationary objects 200 to 300 feet apart with a clear line of sight between them. Using this peg-test area, one person can perform a calibration test in less than one minute.
Other topics that I have written about over the years include pacing, rules of thumb, quick setup with an optical plummet, leveling an instrument, instrument use, chaining, total stations, lasers in construction, planning, preparation, seminars and education, the role of field engineers, dressing for safety, tolerances, and calculating directions with azimuths.
Oldies but GoodiesWhew, I’m glad I did not have to write all of these articles at one time. It makes me tired to think about all of the effort involved.
I realize some procedures that I have written about are no longer used on a daily basis by many surveyors. I even had someone once say to me, “You’re the guy who writes about the old methods.” Yep, that’s me. Regardless, I do strongly believe that some surveyors and surveyors-in-training still need to hear about some of these old methods of layout and measurement because many of them are still relevant. When the power goes out on the total station or GPS system, knowing some of the “old techniques” may save the day.
I think I can conclude that “Back to Basics” will be applicable for a few more years as long as layout points are put in by people.