ES 2670, “Engineering Surveying”

Lab #2: September 26, 2011

Topics: Taping, Pacing & Field Notes

Today, you will use a steel tape to accurately measure a straight line distance greater than the length of the tape

Equipment:

1.  Field notebook

2. Steel tape

3. Stakes or pins

4. Flagging tape

Purpose:

1.  To learn to use a steel tape to measure distances greater than the length of the tape.

2.  To use an ADD tape

·  the decimal part is between the 0 and the 1 so you have to add the distance.

3.  To use a CUT tape.

·  The decimal part is behind the 0 so you have to subtract the distance.

4.  To record the data properly in your field notebook.

Procedure for measuring a distance > the length of the tape

1. Set up a stake at each side of the field

2. Pace the distance between them for an approximate measurement

3. Set up a line of stakes at intervals less than the length of the tape in a straight line to ensure you do not drift while chaining

4. Pull tape to measure the distance; record data as you pull; apply a force of about 20 lb to the tape, and keep the tape level.

5. Add measurements to find the total distance

6. RECORD ALL DATA IN YOUR FIELD BOOK

7. MAKE A NOTE OF THE TEMPERATURE, AS WE WILL USE THIS TO FINE TUNE OUR ANSWERS.

From Elementary Surveying, 9th ed., Wolf and Brinker

Appraising a set of field notes is based on:

Accuracy – this is the most important quality in all surveying operations.

Integrity – a single omitted measurement or detail can nullify use of the notes for computing or plotting. If the project was far from the office, it is time consuming and expensive to return for a missing measurement. Notes should be checked carefully for completeness before leaving the survey site, and never “fudged” to improve closures.

Legibility – notes can be used only if they are legible. A professional-looking set of notes is likely to be professional in quality.

Arrangement – Noteforms appropriate to the particular survey contribute to accuracy, integrity, and legibility.

Clarity – advance planning and proper field procedures are necessary to ensure clarity of sketches and tabulations, and to minimize the possibility of mistakes and omissions. Avoid crowding notes; paper is relatively cheap. Costly mistakes in computing and drafting are the end results of ambiguous notes.

Arrangements of Notes

1.  Project name, location, date, time of day and starting and finishing times. These entries are necessary to document the notes and furnish a timetable as well as to correlate different surveys. Precision, troubles encountered, and other facts may be gleaned from the time required for a survey.

2.  Weather and general conditions. Wind velocity, temperature, and adverse conditions such as rain, snow, fog, heavy traffic, and long or late hours have a decided effect on accuracy in surveying operations. Surveyors are unlikely to do their best possible work at temperatures of 15 degrees or with rain pouring down their necks or at the end of an 18 hour day. These details are important in reviewing field notes, in applying corrections, and for other purposes.

3.  Party. The names and initials of party members and their duties are required for documentation and future reference. Jobs can be described by symbols, such as a drawing of a tripod and instrument for the instrument person, the symbol Phi for the rodman, and the letter N for the notekeeper. The party chief is frequently the notekeeper.

4.  Instrument type and number. The type of instrument used (with its make as serial number and its degree of adjustment) may affect the accuracy of a survey. Identification of the specific equipment employed may aid in isolating some errors – for example, a particular tape with an actual length that is later found to disagree with the distance recorded between its end graduations.

5.  Put your signature in the lower right hand corner of the page.

General comments:

·  When in doubt, WRITE IT OUT! Paper is cheap and it is better to have too much information than too little.

·  Write what you read! Don’t calculate until you’ve written the raw data.

·  Use pen, India ink, or hard pencil. Do not erase or scribble; instead, draw a single line through a small mistake. If the entire page needs to go, put an X through the page.

·  Use a meridian arrow to indicate direction; make the top of the page North, if at all possible.