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‘To{ind the distance AB by the swing
‘offset method, the head chainman
tached the end of the tape to one end
othe ne a5 al 8 and describes an arc
‘with center 8 and radius 100m. The
‘ear choinman stationed at lines nthe
tend cl he tapa wth some distant object
250 and directs the setting of ins at
poinsa and b where the endo he tape
‘tossed ine AO. A point C midway
between a b les on the perpendicular
8B, Apinis setatC, andthe distances
‘BC and CA are measured fo obtain the
neces aaa cpu he ng
of AB,
So4
‘TAPE CORRECTION
‘Ang was determina fo bs 2885.25 m. when
measured wit a 30m. sel tape suppored
Sowa trot pial digste
mean temperature of 35°C, Tape used ie of
andar eng a 20 unde pal of 8 Fy:
Groce-secSona area of ape Is 0.93 qian,
Coefficient of thermal. expansion Is
0 0006118, Modus of easly of lpe i
2108 kgfom
© Oetermine the err of the tape due to
change n temperate,
® Cetormine the erat due to tension,
® Oeternine te comectod length ofthe ne.
Solution:
© Temp. corecton:
GemT-T)
= .0000116 (2395 2535-29
Gyeeaatsim
© Tenslon conection:
celal
ae
oo Gam
Gp#-00089m
D Comncted length:
+L = 205 25 +0.4168 - 0.0389
b= 23986269,
25
‘A 501 tape wa standardized ad was found
(0 be 0.0082 m, 100 tong than the standard
feng aan observed temperature of 56°C and
4 pull of 15 bls. The same tape waa used fo
‘measure a certain distance and wes recorded
(o be 679.82 m. lang a an abserved temp. of
{68°C ond a pull cf 15 kilos. Cooffclent of
Feat expansion is 00000116 m7.
© Detar sce onprt
® Doterrine te otal crecton.
© Determine the ie length a the ine
Solution:
‘Standard temperate:
CreK (Ty Ty) Ly
+ 0.0042 = 0.000016 (58 -T;}50)
+ 000082 = 0.03364 0.00058 7}
7 = 5078 (snd temo)
Total eerecton’
CreKIT-T)Ly
Cy =0,000016 (68 - 50.76)50)
Cr=00 (ape too ng)
e
s
relearn = TOON G* CH,
Toweorecon=opsiim 7 Ve
The Mery
© Tslengtn of ine
(Carected hor. stance = 673.92 + 0.1348
Comected hor. stance = 674 085 m.
‘A-50 m, sted tape was stindardtzed and
suppported throughout is whole length and
foun io be 0.00206 m. nger at an served
temperate of 318°C and a pul of 10 hos.
This tape was used fo measure a Ene which
‘was found (0 be 662.702 m. al en average
{temperature of 246°C using ihe same pul
Use coefficient of enpanson of 00000116 m:
er degree centigrade,
(© Comput th standard temp,
Compute the tl ep. coeeton.
Conte corel Engh ah he
Solution:
‘Standard lerperate:
Cr=K(Tps TIL
0.00206 = 00000116(38- 7,X80)
31a
©
Toa correction:
Cy=K(Ty- TIL
67 =00000116(246- 7827450)
¢7=000218 (ton sho)
Teal caecons 02212
Teta cretion = 0.02823 m,
Coected length of ine:
Corected hottortal distance
= 662702-002821
= 68207377
ABAD)
0.01 G13!TAPE CORRECTION
S-5
‘@ Whatls he true horizontal distance?
Solution:
© Actual length:
Cr=K(T2- Tp ly
Cr = 0.00001 16(5 - 20(30.005)
Cr =- 0.00522 mm
p= Filta
AE
Total correction = - 0.013 m
‘Actual length of tape during measurement
730.005-0013
'=29.992m.
@ Total error:
Too short by = 30 - 29.992
Too short by = 0.008 m
Tel ors 7222008)
Total ear = 0.126 m. (to be subtracted}
® True hortzontal distance:
Horizontal Distance
Comected incined distance
= 47290- 0.126
2472714
oo
80°27
n= 472.774 (003)
h=14183m
(4.1837
Correcton fr sope * 3 era ray
Correction far stop = 0.213m_
Comected horizontal distance
= 472714 -0.213
= 472.561 m.
® What is the errorin area in sq.m.S-6
TAPE CORRECTION
Solution: Solution:
© Actual length: © Cross-sectional area:
Cr=K(T2-T3) Ly A100) 1004786) _ 5 67 Net
Cr = 0,000016(30 - 20}(30.002) 1000 : j Lo
Cr=0.003481m (too tong) A=Q0M sam Wirg,? Ves)
Actual length of tape during measurement a
= 30.002 + 0.00348 ® Total correction:
= 3000548 m. CrEK(Tg-TyL
® The area: Cr=7x 107 (20- sig
Therefore the tape is 0.00548 m foo long Cr=0,00035 m.
Forthe 144.95 m side:
Total eror = 4 SSO 925, Pull creation:
{P2-Pi)k
True length = 144.95 + 0.026 Cp= TE
True length = 444.976 m coe 10400
For the 113 m side: 0.034 (2) 10°
_113{0.00548) | Cp=0.009m
Raters et Comrection = 0.00085 + 0.000
Tae length = 113 +0.021 Cometon= 02085 m
True fongth = 113.021 m
True area = (144 976)113.021) No.of ape fengths = 208 = 4.396
\\ Tre area = 16,385.33 mi? Total comection = 43080 (0.00035)
© Enrinaea: Total correction = 0.0403 m
Eroneous area = (144.95(113)
Erroneous area = 16,379.35 m2
Error in area = 16,385.33 - 16,379.35
Error in area = 6982 m?
@ True length of baseline:
True length of basefne = 430.60 + 0.0403
True length of Baseline = 430.6403 m
‘Abaseline was measured using a 100 m. tape’
which Is standardized at 15°C with a standard
pull of 10:kg. | The recorded distance was
‘found out to be 430.60 meters. Al the ime af
‘measurement the temperature was 20°C: and.
the pull exerted was 16 kg. The weight of one
-cubic cm of steel is 7.86 gr. weight of tape Is
2.87 kg. E = 2x 108 kglom?, K= 7x 107
we. z
® eae a
®. Cobb taed arcen
‘D. Compute the true length of the basa line.
‘A’30 m. steel fape weighing’ 1.45 kg is of
‘standard length under a pull of 5 Kg supported
for full tength.. The tape.was used In
measuring a fine 938.55 m, long on a smooth
tavel ground under a steady pat of 10 kg.
a
Assuming E = 2 x 10° kgfom’ nd the unit
‘weigh! of steel to ba 7.9 x 10° kgfom’,
©. Determine the cross-sectional area of the
tape in cn’,
@ Determine the correction for increase in
tension, :
@® Determine the correct.length ‘of the line5-7
TAPE CORRECTION
Solution:
© Cross-sectiona! area of tape:
WEALYs
1.45 = A (9000)7.9) x 10 Ackil engineer used 1 30 m tape in measuring
A= 0.061 cm? an Inclined distance, The measured length on
® Pull Correction: the siope was recorded to be 459.20 m long.
(P-P)L- ‘The difference in elevaion between the Initial
“ae point and the end point was found to be
125m. The 30m tape is of standard length at
cp, ‘a temperature of 10°C and a pull of 50H.
‘P 0.061 (2x 10°) During measurement the temperature reading
Cp=+0.00123 ooorza Was 1B ond We ape wna sipped ic
= 9200123 (938 55) ‘ends with an applied pul of 75N. The cross-.
Tetal Conecton = "30 sectoral area of he tape ls 650 mn? andthe
Total Correction = + 0.038 m. modulus of elasticity is 200 GPa. The tape
® Correct length of line:
Covrected length = 93855 + 0.038
Corrected length = 938,588 m.
A sleel tape with @ coefficient of linear
expansion of 0.00001 16 per degree centigrate
Is knawn fo be 0 m. lang at 20°C, The tape
was used fo measure a line which was found
tobe $32.28 maters lori when the temperature
‘was 35°C. Determine the following:
© Temperature comection per fape teng’h,
® Temperature correction for the measured
(line.
@ Corrected length of the ine.
Solution:
© Temperature correction per tape length:
CreK(T- TL
C= 0,0000116 (35 - 20,50)
r= 0.0087 m. too long
Temperature correction for the measured
tne:
Te > oat
a S20 .00087
Total correction = + 0.0926 m.
a
Comected length = 5323726. 'm.
‘has a mass of 0.075 kgim. K = 0.000116"
me.
oO Pelee i a ctmem pebe
@ deme th caret bsp.
® Determine the hocznntal distance.
Solution:
© Total correction per tape length:
Cr=K(T2-Ty) by
r= 0.000016 (15- 10)(30)
Cr=+0.00174m
Pull correction:
Pa Paddy
Op aE
5
"550 00% 10)
p= +0,00058 m
Sag Correction:
c= He
S* 24
c (0075x981? 0
“s 2475)
Cs= 0.10827 m
Total correction per tape length:
00174 + 0.00058 - 0.10827
0.10595 mS-8
TAPE CORRECTION
® Correction for slope: ® Tolal correction:
Tat eorcton = ABAD oat 7)
Te as!
Total correction = + 1.622 Cr = 0.000116 (624.9932 - 20)
Garect slope alstance = 459.20 1.622 Cy=+0.087 (too lag
Carect slope alstance » 457.578 m
i
Cs*25
252
Os* 31457578)
Cs= 0002
© Horizontal distance:
Corected
‘A steel tape is 100 m. long at a temp. of 20°C
gota pal ‘twas used to measure a
distance of 624.95 m: at a temp. of 32°C with
‘an applied pull of 15 kg. during measurement
with the taps supported at .both ends.
Coefficient of thermal expansion Is 00000116
m’c and a modulus of elasticity of 2 x 108
kg/cm, Welght of tape ts 0.04 kg/m, anda
«ross sectional area of 0.08 em?
(© Compute the sag correction,
® Cares oe een:
and temperature.
® Compute be comected engh ofthe fine by
applying the combined corrections for
Jension, sag and temperature.
Solution: :
@ ‘Seg compcfont ‘
= ch
1 = me %
3 .
cx sm,
(0.04)4 (24.95)3 _
C= age
Total sag corection
= 6(0.296) + 0.005
Total sag corection = 1.781 (too short}...
‘A Gil engineer used a 101m tape which is of
standard length at 32°C in nieasuring a certain
dlistanca’and found out that the fength of tape
have different lengths at different tensions
were applied as shown. K =<0,0000116 mic"
Length ottape _Ter.sion Applied
99,988 m 10ig
90.962 m 4g
100.003m £20k
‘®. What tension must be eoplied fa the tape
at a temp. of 32°C sp Frat it would be of
Standard
fength?
@ What tension must be applied to the tape
‘at a temp, of 40.6°C 90! hat M would be of -
‘standard length?
@ What tension mus! be g5plied to the tape
ata temp. of 30°C so taal it would be of
standard length? :TAPE CORRECTION
Solution:
@ Tension applied at 32".
“ wt |,
om aut
x _ 0.008
6 oo
x=4.36 kg,
Tension applied = 18.36 kg .
@ Tension applied at 40.6"
‘Temperature corection:
Cr=K(T2-Ty)L
Cr = 0.000116 (40.8 - 32) 100
C= 0.00998
Actual length of tape at40.6°C Tension
99.986 + 0.00998 = 99.99598
‘99.992 + 0.00998 = 100.00198
100.003: + 0.00998 = 10001298
wmf anton UI,
100,00198
x _ 0.00402
4° 0.006
4= 2.68 kg
Tension to be applied = 10+ 2.68
Tension to be applied = 12.68 kg
® Tension applied at 30°C:
Temperature comection:
=K(T2- ML
0000116 (30 - 32) 100
Cy=-0.00232
10kg
14g
201g
14)
Actual length of tape at40.6°C Tension
99.986 - 0.00232 = 9998368 10kg
99.992 = 0.00232 = 99.98968 14kg
100.003 - 0.00232 = 100.00068 20kg
jt ~(}
x 0.01032
5 “O01T
¥=§63kg
.+ Tension applied = 14 + 5.63
Tension appiied = 19.63 kg
A.50 m. tape of standard length has a weight of
0.05 kg/m, with a cross sectional area of
0.04 sq.em_ It has a modulus of elasticity of
2.10 x 108 kg/em?, The tape is of standard
length under a pull of 5.5 kg when supported
throughout is length and a temp of 20°C. This
tape was used to measure a distance between
A and B and was recorded to be 458.65 m.
long. At the lime of measurement the pull
applied was 8 kg. with the tape supported only
atts end points and the temperature observed
‘was 16°C, Assuming coefficient of linear
‘expansion of the tape is 0.0000116 mC.
‘© Compute the correction due to tha applied
pull of 8 kg.
@ Compute the comection due to weight of
tape.
® Compute the true length of the measured
fine AB due to the combined effects of
tension, sag and temperature,(8 -594458.550
= oon 2.10 x108) 24m
@ Number of paces for the new line:
893 = 893.5 + 891 +8955
No. of paces=
Na of paces = 693.25
Distance of the new tine:
Distance of new fine = 893.25 (0.691)
Distance of new line = 617.236 m.
1s = + 1.832m. (always negative)
® Tre length of measured line AB:
Gr=K(Tz-T)L
Cr= 0.00001 16 (18 - 20/458.65)
Cr=-0011m.
Tolal correction = | baal 1832-0014
Total correction = - 1.6291m.
True length AB= 458 65- 1.829
True length AB = 456.821 m.
A line 100 im. long was paced by a surveyor’
four times'with the following data. 142, 145,
145.5 and 146,’ Then another line was paced
for four limes again with the following results,
893,893.5, 891 and 805.5. *
© Oetermine the pace factor,
@® Determine number of paces for the new
line.
®, Determine the distance of the new fine.
Solution:
® Pace factor:
No. of paces 3 Mb Ss 185 8
No. of paces = ‘Wass
Pace factor =O = 0694
: m=
This sides of a square lot having an area
of 2.25 hectares were measured using a
100 m. tape that was 0.04 m. too short.
Compute the error inthe area in sq.m.
‘The correct distance between two point is.
220.45 m._Using a 100 m. fape that is “x
m. too long, the length to be laid on the
ground should be 220.406 m. What Is the
value of "x"?
The distance from D tb E, as measured, is
165.2 m. If the 50 m. tape used Is 0.01 m.
too short, what Is the correct distance in
Solution:
Aa22aDbeCtaES yi! ao
Eorin area=225-22482 = ui,
Enor in area = 0.0018 hectares
Erorin area = 0,0018 x 10000.”
Emo in area = 18 sq.m.
Note: 1 hectare = 1000 sqm.
Corrected distance:
Corect dtance = 1652 922901)
Conect nce = 168167