FIELDWORK NO. 3: TAPING ON A SLOPING GROUNDMASALUNGA, Kimberly T.

OBJECTIVE

1. To develop the skills in determining the horizontal distance of a sloping ground by breaking the tape method up and down the slope.

MATERIALS AND METHODS

Instruments to be used:1. Two range poles2. Chalk and/or one set of marking pins3. 2 plumb bobs4. 50 meter tape

PROCEDURE:

BREAKING THE TAPE METHOD

1. The professor designates two points on a sloping ground to be measured by the students and marks the lower point down the hill as A and up hill as B. ( Note: Make sure that point A with a range pole will be visible from B to keep the path straight. )

2. Set or hold range poles behind points A and B or outside the course AB. These poles will aid the students to travel in a straight path. Front tapeman holds the reeled out tape while the 0-mark elevated by about breast high is held by the rear tapeman directly over point A with the use of the plumb bob.

3. Front tapeman aligns himself along the course AB with the aid direction given by the rear tapeman. The front tapeman while holding the end of a tape length pulls the tape taut to make the tape horizontal. (Note: Extra care is needed to make sure that the tape is along AB and the ends of the tape are on one horizontal level.)

4. Front tapeman drives a marking pin on the ground or marks a chalk on the pavement once the tape is horizontal and the course is a straight path from A to B.

5. The rear tapeman leaves point A and moves up the slope to the pin previously driven by the front tapeman. Front tapeman now moves further upward.

6. Procedures 3-4 are repeated until all possible full tape length can be accommodated by the course.

7. The last partial tape length is measured if possible with the 0-mark of the tape now held at B. All data must be carefully recorded on the computation sheet provided for this field work.

MEASURING DOWN THE SLOPE

1. The same two points will be used by the students but this time the 0-mark is now held by the front tapeman and they are to travel down the slope on a course from B to A.

2. Set or hold range poles behind points A and B or outside the course AB. These poles will aid the students to travel in a straight path. The front tapeman now must hold the 0-mark about a breast high with the aid of a plumb bob.

3. The rear tapeman on the upper hill B now guides the front tapeman to straighten his path. The rear tape man holds the end of the full tape length.

4. Once the alignment is attained, the front tapeman drops the plumb bob and drives a marking pin or marks the pavement with a chalk where the plumb bob dent is found.

5. The rare tapeman leaves point B and moves down the slope to the pin previously driven by the front tapeman. Front tapeman now moves further downward.

6. Procedures 3-4 are repeated until a full length can be accommodated by the course.

7. The last partial tape length is measured if possible with the 0-mark of the tape now held at

B. All data must be carefully recorded on the computation sheet provided for this field work.

DISCUSSION & CONCLUSION

Range pole is a surveying instrument used for marking the position of stations and for sightings of those stations as well as for ranging the straight lines. A plumb bob is used to check if objects are vertical. A plumb bob consists of a piece of metal (called a bob) pointing downwards, which is attached to a cord. When the plumb bob is hanging free and not moving, the cord is vertical.

The term breaking tape is used to describe the procedure for measuring directly horizontal distance on sloping ground, or through obstacles that do not permit the use of a full tape length. The procedure used in breaking tape is the same as ordinary chaining on level ground, except that the distances are measured by using portions of a tape.

I can say that the field work that I have conducted with my group mates was successful because the data that we have gathered are good. And the distance we have computed is near to the actual distance of the ramp. For the improvement of this field work, it is important to follow the procedures correctly and to set the materials properly because wrong set up might cause inaccurate results.

After conducting the activity, I have learned how to use the tape method in measuring the horizontal distance of a sloping ground. Also, I have learned that in able to have accurate result the tape should be both making 90 degrees with the range pole. Also, to avoid sagging of the tape, tape should be maximized at 10 meters.

The sources of errors may occur in (a) tape may differ in actual length from its nominal graduates length because of a defect in manufacture or repair, repair, or as a result of kinks. (b) Natural errors: The horizontal distance between end graduations of tape varies because of the effects of temperature, wind, and weight of tape itself. (c) Personal errors: Tapeman setting pins, reading the tape, or manipulating the equipment.

ACKNOWLEDGMENT & REFERENCE

I would like to express my deepest appreciation

to all those who provided me the possibility to

complete this report.  A special gratitude I give to

our Professor, Engineer Cervantes, for guiding us

in the field work and explaining the methods and

technique in conducting the activity.

Furthermore I would also like to acknowledge

with much appreciation the crucial role of the

staff CEGE Department of Mapua, who gave the

permission to use all required equipment and the

necessary materials to complete the field work. A

special thanks goes to my group mates who

helped me in finishing the activity successfully

and providing me the data needed in completing

this report. I would like to acknowledge their

effort to accomplish the activity successfully

though it is very hot outside.

I would like to thank God for the wisdom and

strength that He has given me to do all the

activities.

To the following sites, for the having similarly

been among the references that oriented the

body, the framework, of this report:

http://www.fao.org/docrep/r7021e/r7021e02.htm

http://web.itu.edu.tr/tari/surveying-I/week_3.pdf

http://engineeringtraining.tpub.com/14069/css/14069_419.htm