Field work #1 Barroja PDF

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BARROJA, AQUIMEL P.BSCE-PROBLEM : PACINGOBJECTIVES : a) To determine individual pace factor. b) To measure distance by pacing.L A B E X E R C I S E O U T L I N EA. INSTRUMENTATION AND ACCESSORIES: Range poles, Steel Tape, Markers (hubs, paint, chalk, or crayons).B. PROCEDURE: 1. Determining Pace Fac...

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BARROJA, AQUIMEL P. BSCE-2206 PROBLEM: PACING OBJECTIVES: a) To determine individual pace factor. b) To measure distance by pacing.

LAB

EXERCISE

OUTLINE

A. INSTRUMENTATION AND ACCESSORIES: Range poles, Steel Tape, Markers (hubs, paint, chalk, or crayons). B. PROCEDURE: 1. Determining Pace Factor. a) Select a straight and level course and on both ends establish markers at least 90 meters apart. Designate these end points as A and B. b) Walk over the course at a natural pace or gait starting with either heel or toe over point A and count the number of paces to reach point B. c) For succeeding trials, walk from B to A, then A to B, until 5 trials are completed, and the number of paces recorded accordingly. d) Refer to the accompanying sample format for the recording of observed field data.

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TRIAL

LINE

1

AB

TAPED DISTANCE (m)

NUMBER OF PACES

MEAN NUMBER OF PACES

PACE FACTOR (m/ pace)

135.4 paces

0.6647 m/pace

135 ¼ 90m

2

BA

133 ¾

3

AB

134 ½

4

BA

136

5

AB

137 ½

Measuring Distances by Pacing. a) Define or establish the end points of another level course whose length is to be determined by pacing. Designate these end points as C and D. b) For the first trial, walk over the course from C to D at a natural pace and record the number of paces. Then, walk from D to C and again record the number of paces. c) Repeat the above procedure until all five trials are completed. d) After the field data is recorded, make an actual taping at the course CD to determine the taped distance. e) Refer to the accompanying sample format for the recording of observed field data. TRIAL LINE 1 2 3 4 5

CD DC CD DC CD

NUMBER OF PACES 150 ¾ 149 ¾ 151 ¼ 148 149 ¼

MEAN

149.8 paces

PACED TAPED RELATIVE DISTANCE DISTANCE PRECISION

99.5721m

100m

0.4279/100 or 1/200

C. COMPUTATIONS: 1.

Computing Pace Factor (PF). a. Get the sum of the number of paces for the five trials performed on course AB then compute the mean number of paces. b. Divide the known or taped length of course AB by the mean number of paces for AB to determine the pace factor. Solution: L = 90m n1 = 5 Sum = 677m M1 = Sum/n1 = 677/5 = 135.4paces PF = L/m1 = 90m/135.4paces = 0.6647m/paces

2.

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Computing Paced Distance (PD)

a. Get the sum of the number of paces for the five trials performed on course CD and compute the mean number of paces. b. Multiply the mean number of paces for CD by the pace factor to obtain the paced distance. Solution: n2 = 5 Sum = 749m M2 = Sum/n1 = 749/5 = 149.8paces PD = 149 x 0.6647 = 99.5721m 3.

Computing Relative Precision (RP). a) Determine the difference between the taped distance of CD and the paced distance of CD. b) Divide the difference by the taped distance of CD and reduce the numerator to unity to determine the relative precision Solution: TD = 100m PD = 99.5721m RP = (TD-PD)/TD = (100m-99.5721m)/100m = .00479 = 1/233.6 or 1/200

D. REMARKS, HINTS & PRECAUTIONS : 1. The ends of the assigned courses should be marked with either hubs, marking pins, or by chalk marks if on pavement. 2. Range Poles are set or held behind the end points to serve as guides or markers during actual pacing. 3. A steel tape. should be used in laying out or in measuring the actual lengths of courses assigned for pacing. 4. When, taping, two measurements should be made for any line and the mean recorded as its actual length. 5. The length of a single step is termed a pace. It may be measured from heel to heel or from toe to toe. Also, each two paces or a double step is called a stride. Fig. 1 Length of a pace.

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6. Pacing consists of. counting the number of steps in a required distance and is best done by walking with natural steps. 7. Pacing is used only when approximate results are satisfactory such as for estimating distances used for sketching and in reconnaissance surveys. Pacing is also used as a means of checking. distances measured by more accurate methods. 8. To keep one on the line while pacing, it is a good practice to fix one's eyes on a distant object on the range behind the pole at the farther end of the line being paced. 9. A partial pace at the end of the line should be figured out to the nearest onefourth pace. 10. The accepted precision for measuring distance by pacing usually varies from 1/200 to 1/500. 11. Reject measurements that vary from the mean by more than three percent. 12. If the computed relative precision of the set of measurements is greater than one part . in two hundred, the measurements should be гереated. E. FIELD NOTE

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F. CONCLUSION I therefore conclude that pacing is a simpler method of measuring distance or land dimensions with a little margin of error. It is also crucial to always remember your Pace Factor to measure land area without using any measuring tool. It is also evident that the Pace Factor is smaller when the number of steps you made while walking is greater, and it is bigger when the number of steps you made is lesser. Also, you could make an accurate Pace factor if you made your pacing natural and consistent, with that, you could always utilize it anytime. It is also noticeable that the Relative Precision is closer to the accepted precision (1/200-1/500) when the difference between the Taped Distance and Pace Distance is lesser and that small differences can affect the measurement of longer distances. Overall, it is good to use pacing as a method when there is no any measuring material or equipment but it is still advisable to bring a measuring tool to cover a more accurate measurement. F. DOCUMENTATION

Measuring a 90m long straight and level course.

Putting a mark to the starting point and label it as Point A

Putting a mark to the end point and label it as Point B

Writing down all the data after walking from point to point....