Surveying Field (Laboratory) - Laboratory Report 2 DPD Method, DMD Method, Bearings PDF

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Summary

In this Laboratory report, you will learn how to use different methods on measuring an area with irregular shapes of lots. Furthermore, the example problems will help you master different problems involving DPD and DMD method....

Description

COLLEGE OF ENGINEERING AND TECHNOLOGY CIVIL ENGINEERING DEPARTMENT CIV 0211.1 Fundamentals of Surveying (Field) LABORATORY REPORT NO. 2: Taping and Area Computation I.

PRINCIPLES OF THE ACTIVITY Taping is the linear measurement of the horizontal distance between two points using a surveyor's tape. Observation of horizontal distances by taping consists of. applying the known length of a graduated tape directly to line a number of times. Due to error in judgement and execution, this method incurs inevitable error given by the formula:

The sum of the meridian distances of the ends of a survey line. In practice, assuming a closed traverse with the meridian of reference passing through the initial station, the double meridian distance (DMD) of the first course (line) is equal to the departure of that course; the double meridian distance of each succeeding course (line) is equal to the double meridian distance of the preceding course, plus the departure of the preceding course, plus the departure of the course itself. If the DMD of each course is multiplied by the latitude of the corresponding course, double areas are obtained, from which the area of the tract can be obtained. By a strictly analogous procedure, double parallel distances (DPD) can be computed, using the latitudes of the successive courses instead of departures, and using an east-west line as the reference parallel. II.

RESOURCES 1 unit

III.

Measuring Tool

PROCEDURES A. Determination of a Distance by Taping 1. Mark two random points, X and Y. The measured/estimated distance should be known (10m to 50m dependent on available space in your area). 2. Using a measuring tool (ruler, tape measure, meter stick, etc.), measure the distance by a number of trials (minimum of 3 trials). 3. Get the average of the trials and solve for the relative and percent error considering the actual or estimated distance of the two points.

1

B. Determination of an Area of a Closed Traverse by DPD Method. 1. Solve for the area of the given traverse using Double Meridian Distance Method.

2. Consider necessary adjustments to close the traverse. C. Determination of an Area of a Closed Traverse by DPD Method. 1. Solve for the area of the given traverse using Double Parallel Distance Method. Given lengths in meters.

2. Consider necessary adjustments to close the traverse.

IV.

DATA & RESULTS Table 1.1. Results of Taping a Distance TRIAL 1 2 3 4 5

LINE XY YX XY YX XY

MEASURED DISTANCE 16.28 16.3 16.50 16.40 16.12 2

NO. OF PACES 24 23 23 25 24

Table 1.2. Tabulation of Data for DMD Method

AB

LENGTH (m) 172.917m

BC

247.108m

S 49°38’ E

-160.04610

+188.27535

0.000477

0.002706

CD

281.240m

S 43°26’ W

-204.22940

-193.35534

0.000609

0.002779

DE

125.486m

N 39°22’W

+97.01357

-79.59337

0.000289

0.001144

EA

179.262m

N 18°53’W

+169.61404

-58.01674

0.000506

0.000834

SUM

1006.013

+0.003

+0.01446

+0.002173

+0.009515

LINE

LINE

CORR LATITUDE

CORR DEPARTURE

BEARING

LATITUDE

DEPARTURE

N 55°37’ E

+97.65089

+142.70456

0.000291

0.002051

LENGTH (m)

ADJUSTED LATITUDE

ADJUSTED DEPARTURE

DMD

DOUBLE AREA

AB

172.917m

97.6505988

142.7025

142.7025088

13934.98544

BC

247.108m

-160.0465773

188.2726

473.6776615

-75810.48845

CD

281.240m

-204.230009

-193.358

468.5921861

-95700.58639

DE

125.486m

97.0132807

-79.5945

195.6395528

18979.63485

EA

179.262m

169.6135342

-58.0176

58.02746487

9842.243397

0.000827402 ≃0

0.004945481≃ 0

SUM

AREA

128754.2111

211221.28 𝒇𝒕𝟐

Table 1.3. Tabulation of Data for DPD Method LINE

LENGTH (m)

BEARING

LATITUDE

DEPARTURE

CORR LATITUDE

CORR DEPARTURE

AB

285.10

S 26°10’W

-255.882

-125.724

0.0813

-0.0616

BC

610.45

N 75° 25’W

153.704

-590.783

0.174

-0.1319

CD

720.48

N 15°30’ E

694.276

192.54

0.2054

-0.1557

DE

203.00

S 1°42’ E

-202.911

6.022

0.0579

-0.0439

EA

647.02

S 53°6’ E

-388.484

517.412

0.1844

-0.1398

SUM

2466.05

0.703

-0.533

0.703

-0.533

LINE

LENGTH (m)

ADJUSTED LATITUDE

ADJUSTED DEPARTURE

DOUBLE AREA

AB

285.10

-255.9633

-125.6624

-255.9633

32164.96259

BC

610.45

153.53

-590.6511

-358.3966

211687.346

CD

720.48

694.0706

192.6957

489.204

94267.50722

DE

203.00

-202.9689

6.0659

980.3057

5946.436346

EA

647.02

-388.6684

517.5518

388.6684

201156.03

SUM

2466.05

0

0.0001 ≃ 0

AREA

V.

DPD

272611.141𝑚2

CALCULATIONS

3

545222.2822

A. Determination of a Distance by Taping

Exact Distance of line XY = 16.30 m Average of Trials: 𝐴𝑉𝐺 =

16.28 + 16.3 + 16 .50 + 16.40 + 16.12 = 𝟏𝟔. 𝟑𝟎𝟒𝒎 5

Relative Error: 𝑅𝑒𝑟𝑟𝑜𝑟 =

|16.304 − 16.30| = 𝟎. 𝟎𝟎𝟎𝟐𝟒𝟓 16.30

Percent Error: |16.304 − 16.30| ∗ 100% = 𝟎. 𝟎𝟐𝟓% 16.30

𝑃𝑒𝑟𝑟𝑜𝑟 =

B. Determination of an Area of a Closed Traverse by DMD Method.

[Convert ft – m] 𝑨𝑩 = 𝟓𝟔𝟕. 𝟑𝟒 𝒇𝒕 𝒙 𝑩𝑪 = 𝟖𝟏𝟎. 𝟕𝟔 𝑓𝑡 𝒙 𝑪𝑫 = 𝟗𝟐𝟐. 𝟕𝟓 𝑓𝑡 𝒙 𝑫𝑬 = 𝟒𝟏𝟏. 𝟕𝟐 𝑓𝑡 𝒙 𝑬𝑨 = 𝟓𝟖𝟖. 𝟏𝟔 𝑓𝑡 𝒙

[Computation of Lat and Dep] Using calculator features (Rec)

𝟏𝒎 = 𝟏𝟕𝟐. 𝟗𝟏𝟕𝒎 𝟑. 𝟐𝟖𝟏 𝒇𝒕 𝟏𝒎 = 𝟐𝟒𝟕. 𝟏𝟎𝟖𝒎 𝟑. 𝟐𝟖𝟏 𝒇𝒕 𝟏𝒎 = 𝟐𝟖𝟏. 𝟐𝟒𝟎𝒎 𝟑. 𝟐𝟖𝟏 𝒇𝒕 𝟏𝒎 = 𝟏𝟐𝟓. 𝟒𝟖𝟔𝒎 𝟑. 𝟐𝟖𝟏 𝒇𝒕 𝟏𝒎 = 𝟏𝟕𝟗. 𝟐𝟔𝟐𝒎 𝟑. 𝟐𝟖𝟏 𝒇𝒕

LATITUDE AB = Rec(172.917, 55°37’) -

+97.65089

+142.70456

BC = Rec(247.108, 49°38’) -

-160.04610

+188.27535

CD = Rec(281.240, 43°26’) -

-204.22940

-193.35534

+97.01357

-79.59337

DE = Rec(125.486,39°22’) EA = Rec(179.262 ,

[Correction for Latitude]

𝑨𝑩 = 0.003 𝒙 𝑩𝑪 = 0.003 𝒙

𝑪𝑫 = 0.003 𝒙 𝑫𝑬 = 0.003 𝒙 𝑬𝑨 = 0.003 𝒙

𝟏𝟎𝟎𝟔.𝟎𝟏𝟑 −160.04610

𝟏𝟎𝟎𝟔. 𝟎𝟏𝟑 +97.01357

𝟏𝟎𝟎𝟔. 𝟎𝟏𝟑 +169.61404

𝟏𝟎𝟎𝟔. 𝟎𝟏𝟑

18°53’)

+169.61404

-

-58.01674

[Correction for Departure]

+97.65089

𝟏𝟎𝟎𝟔. 𝟎𝟏𝟑 −204.22940

DEPARTURE

= 0.000291

𝑨𝑩 =

= 0.000477

0.01446 𝒙

𝑩𝑪 = 0.01446 𝒙

= 0.000609

𝑪𝑫 = 0.01446 𝒙

= 0.000289

𝑫𝑬 = 0.01446 𝒙

= 0.000506

𝑬𝑨 = 0.01446 𝒙

[Adjusted Latitude]

142.70456

𝟏𝟎𝟎𝟔.𝟎𝟏𝟑 188.27535

𝟏𝟎𝟎𝟔. 𝟎𝟏𝟑 193.35534

𝟏𝟎𝟎𝟔. 𝟎𝟏𝟑 79.59337

𝟏𝟎𝟎𝟔. 𝟎𝟏𝟑 58.01674

𝟏𝟎𝟎𝟔. 𝟎𝟏𝟑

= 0.002051 = 0.002706 = 0.002779 = 0.001144 = 0.000834

[Adjusted Departure]

AB = +97.65089 - 0.000291 = 97.6505988

AB = 142.70456 - 0.002051 = 142.7025088

BC = -160.04610 - 0.000477 = -160.0465773

BC = 188.27535 - 0.002706 = 188.2726438

CD = -204.2294- 0.000609 = -204.230009

CD = -193.35534 - 0.002779 = -193.3581192

DE = 97.01357- 0.000289 = 97.0132807

DE = -79.59337 - 0.001144 = -79.59451404

EA = 169.61404 - 0.000506 = 169.6135342

EA = -58.01674 - 0.000834 = -58.01757391 4...