ASM 215

LABORATORY #5 - FIELD OPERATIONS USING A TAPE

Name: ______Lab Section ______

PURPOSE: The purpose of this lab exercise is to learn the basic procedures for taping.

OVERVIEW:Each crew will have to determine the horizontal, vertical and slope distances between two markers by taping, correcting the measurements and using trigonometry. Each distance will be measured twice. You will need to correct measured distances for temperature, pull, sag, alignment and slope whenever appropriate.

FIELD BOOK SETUP:

The title of this lab is: TAPING FIELD OPERATIONS
The location title is: AGRICULTURAL MALL, PURDUE UNIVERSITY, West Lafayette, IN.

Include crew and weather information in appropriate field book sections. The temperature will be necessary later to calculate the corrections.

The equipment list is:
Steel Tape (100.00 ft)
Chaining Pins (11)
Range Poles (2)
Plumb Bob

Automatic Level

Tripod

Grade Rod

Monuments (markers) used in the survey should be described well enough for other crews to uncover at a later date.

For example:
MRKR-X: Approximately 41 ft N of NW corner of ABE bldg and approximately 26 ft E of intersection of concrete walks, find a concrete bench.

The location sketch should include ABE, S. University St., the monuments and any other significant information. Try to keep the North arrow pointing upwards and remember to indicate whether the sketch is to scale or not.

PROCEDURES:

I. Slope Distance

a. Measure the slope distance of the grassy knoll in front of ABE by having one team member stand with one tape end at Marker 1 on the top of the knoll. Another team member will take the other tape end and proceed to walk toward Marker 2 at the bottom of the knoll. Record the distance (slope distance – do not adjust for the slope). Record the length shown on the tape in your fieldbook.

b. Measure the horizontal distance between Markers 1 and 2 twice by breaking the tape (not literally) as explained in class and in the textbook. Start with the rear tape person holding the tape at Marker 1 and proceed downhill. The forward tape person will need to use precise plumbing at Marker 2. A third crew member should stand at a distance and direct the tape persons in keeping the tape horizontal. The forward tape person will need to make the final measurement by precise plumbing over Marker 2.

II. Horizontal Distance

a. Have the rear tape person stand at Marker 3 in the Ag Mall. The forward tape person will then proceed towards Marker 4. When the chain reaches 100.00 feet, another team member will place a chaining pin at that point. The rear tape person will then move to that pin and repeat the previous steps until the forward tape person reaches Marker 4. Record the distance measured in your fieldbook.

III. Comparing Methods of Determining Distance

a. Using the automatic level set up by the lab instructor, ensure that they instrument is level and record the upper and lower stadia readings on the grade rod at Markers 3 and 4. Calculate the distance from the instrument to the Markers and add together to determine the distance between the two markers.

distance between instrument and rod = (upper stadia – lower stadia) * 100

b. Pace the distance between Markers 3 and 4. Using your pace length determined in Lab 2, calculate the distance between the markers.

c. Compare the distance between markers measured with the tape in part II with the distance calculated from stadia in III.a. and the distance calculated from pacing in III.b. Explain which measurement is likely more accurate and indicate potential sources of error for each method.

NOTES:

  • Be sure to record all readings directly into your field book
  • Do parts I and II twice and have different group members do different jobs

CALCULATIONS:

In your field book’s Calculations and Adjustments section:

  • Correct all taped distances for temperature and sag (if appropriate)
  • Average all pairs of corrected distance measurements
  • From the averaged horizontal and slope distances between Markers 1 and 2, compute the vertical distance between these points and the slope angle
  • Distance between Markers 3 and 4

COMMENTS:

Place in your field book any comment that is of relevance in the interpretation of your results.
Standard Temperature: 68°F (20°C)
Standard Pull: 12 lb