lab .field book surveying

*150428F*

Surveying Lab N2 1

Tape Measurement of Lines

On every survey, there will inevitably be a variety of long and short, flat and inclined,

lines to be measured accurately.

A) The figure below shows a short survey line AB marked on the ground by two

pegs. The distance An is shorter than one tape length.

19.733 m

::=:=~:=::=~==:=~~====~'~~~~~I~;~~;~.~!~r~Ir

I

~I~'~1~~6~1~~~I~I~r~'~'~I~~~~~J .19.7 read IlI'Jvr~" . 0.03 GCunt c.ms. 0.003 es.tlmate IT'ffi-S

,...;,P""---__ 1lTJ)m

Measurement of a short line is obtained by the following steps:

1- Unreel the tape and straightening it along the line between the pegs.

2- The zero point of the tape is held against station A by the rear tape person (called

the follower) .

. 37;_~:ff;fiWatd:~tt(1l[0f;flte'!~~eis r.ea<1~g~fiat1~ll8..bY the fbrwal!d t{\I)~p~rson . • • • . '. • c·", .'.""", , _

(caUed the:lead:~r); .a:tierithasbeeiiO<¢~ifUy:ti_tened.

t I' !. ;nf, I! , i; .! ,Ii@, I I I ; I I t i , I !. ~'~', I I • t .', , .012, ,.; t ! , ,

ieIA

: ! pl'! I I I t j I ! f9(8J I, ! 1 t I I I pl9 ; I It, , ! .4. I , I t ,; 1§)1!!,. 1

Ie 10

..

B) On surveys most of the lines will be considerably longer than one tape length and a

sound operational technique is required.

- Two ancillary pieces of equipment are necessary:

1- Ranging rods.

tl- Marking arrows.

ranging roo-

metal shoe

....­I I

! 1

37Smm

-f­

/

morl<:,H] arrow

Measurement of a long line is obtained by the following steps:

" . .

••-·l~·m.{i;rdll()w~r'i'h~l~;iit~f~j~~~· 'li~til~e'~~m$t$t~~i\)nA aild$eleat€rpufls the

tape 'towards stati~n:B. . .

2-When the tap.e has been laid out the leader holds the ranging rod vertically

approximately on the line.

.,. 3- The follower signals to the leader to move it until it is exactly on the line AB .

..

- - . -,- --~'"-----~---- -.--.".~~-~.--- .. -.~----- .. ' --~ ~~. ~ ._------­

4- The tape is tightened between the newly erected rod and station A and an arrow is

pushed into the ground at the 20 mark of the tape .

5- The follower moves forward to this new point and the whole procedure is repeated

for the remainder of the line until station B is reached.

6- The follower gathers the marking arrows and the number of tape lengths measured

is the number of the arrows carried by the follower, the portion of tape between the

last arrow and station B is then measured and added to the number of complete tape

lengths to produce the total length ofthe line.

Group No... -c-----­

Group 'Names:

L

2.

4.

5.

6.

7.

8. --------------------~----------------

9.

10.

Surveying Lab N~ 2

-Linear Surveving

1 I I I

----­t rocl< ----­

I 1

A -E--~

l..oo

I o t.o!

B ® -2:22

fe.n:::.£

Be 2753 27.53

uf

'"

\

Su rveying Lab N!! 2

Linear Surveying

Where comparatively small areas have to be surveyed a linear survey might be used.

The principle of linear surveying is to divide the area into a number of triangles, all the sides of which are measured.

Linear surveying ora site is ol1blin~dbyth:e'f()lbi~i~f.l:~t~ps:

1- Draw a sketch of the site andJocate the north direction on it.

2- Select the traverse station points and mark them with a suitable mark.

I • I" \

I ..~. !.". \ ccrc!""Ate ~1~,--r- ­

/~~: -~ '"" ,,~ t-. :_-.< ;~ '''O::;~-

I - ,'. . • I I-t--., , -.. ~oo m.m .~-.- · ..-'--t·

3- Reference the traverse statiori points to be able to locate them again easily_

4- Establish a framework over the whole site to form a geometric figure, which all sides are to be measured and can be readily plotted;­

8 S"L­ ~

-79"97 ~ A 21.80 F-

c --== -:=---- ­

Group No.

Group Names:

1.

2.

---~---------------------------------

4.

5.

6.

7.

8.

9.

10. -----------------------~-------------

5- All the details (fences, walls, streams, trees, buildings, etc.) are then added to the framework by offsetting.

6- Record the surveying details for each line of the framework on the survey.field book as shown.

2.22

2.20

30.0 .2.05

. 1.82

2.20

o

Be 2753

7 - Finally the survey is to be plotted starting with the framework followed by the det~ils.

j -"'-~-~-'---'----iti--­

6+ N

=

Surveying Lab N~ 3

Bearing Measurement Using Compass

'-.

\

. i ;

! ,

i

.... . M -!-v'.r:g. N:lt" ti,

T:;- True­

".­

SUI-veying Lab N!! 3

Bearing Measurement Using Compass

After this laboratory, the student should be able to determine the forward and back bearings of the lines of a traverse survey.

.The bearing of a line can be defined by its direction relative to north.

Magnetic Whole Circle Bearings (MWeB):

Is the angle measured in a clockwise direction from the magnetic meridian to a line.

True Whole Circle Bearings (TWCB):

[s the angle measured in a clockwise direction from the true meridian to a line.

Magnetic Declina-tion (o):

Is-: the difference between the true and magnetic whole circle bearings_

TrueMagnetic~Nor th

, . -,:." ",:' ','

-:l'brth,: ., :...---t--:.....

\

\ '.

,

J

7;~t;C"1:B\,.-:'.: . , ,mc'gf'\E'ti<::

oechnallor,

__~~-·~~'~r----A x

J

true WeB.

The figure below shows a line joining two stations A and B where the whole circle bearing from A to B is 63°.

N

T N

i r I

\

A

Forv.ord w.c.b Hock wch

8

/

If an observer where to stand at station A and look towards station B he or she would be looking in a direction 63° relative to the chosen north point. In surveying terms, the observer is looking forward towards station B from station A, and the forward whole circle bearing of the line AB is 63°.

If the observer now stood at station B and looked towards station A he or she would be . . ," ':

. looking back along the line, i.e. in exactly the reverse dires:tton.·· ..'

:~thisdirection BAis known as the back whole cirdebearing. Th~ ang~lar v~lueis .the . .• doekwiseangie [rum the north pOInt to th~JineSA, naf[.l(dy{§~a.+ .r80~)-;'": 2flJo... · .

• ::.'., • ,.._ •••_ •• , 0" ' •• : ,_. • - • • • • ~." To

FFom thls;simpl~exampiean equ~tJy simple rule can be deduced ..

Rule: .

"To obtain back bearing/rom forward bearings, or vice versa, add or subtract 180~ "

fhe student has to measure the forward and back bearings for surveying lines to check vhether the difference is 1800 or not.

A

c

Complete the following tables :

Line I F.Bearing B.Bearing Difference

ABI

BC I CA

I

Group No.

1.

2.

4.

5.

6.

7.

8.

9.

10.------------------------------------­

Surveying Lab

Theodolite General Knowledge

0"

lO!1J"?t I

;f­

x

--if ----------­ h

Surveying Lab Kg 5

Theodolite General Knowledge

After this laboratory, the student should be able to measure the angles by using:

(a) Optical Theodolite . .(b)Digital Theodolite_

'Theodolite is.an instrument that is used to measure angles, with an accuracy varying from 1 to 60 seconds.

-!

lol

'---·-'1r

I

I I H I

--_.- ..... i tc 1

! 1v ,- ­

! 58 1 ------ .----- ~ifa:l

r 2'>5<-j

~- Z2Ll ! , 1L-'1__.. _.____ ' .

L. __,___

..-- -------'- -'---'---'

96 ~.:" 2'(: ~ ;,.a ~ tiC

. ,i..!.I'iUflfO~lf1h~... lJ;~1.1

r·--·--·----- -~--!

1102 103

j o~~,.t-I..;~~..~~~."~"I"~'~t I ;

\257 256 \ I

'--_____H______~._J -------- .~.------.

r·-------;· .-­

V : C;OS·,t"l! 0' u ~ u

H 1:::1- ,"08 n q' r 'V Ull ..

Theodolite rending systems

'.-." -.' - - - "' =. ~ ~.- - -.-.·-·••~···.··_·--r·_C:-:::-·_'":.- .-_- ~ -- - •. ~. - - -" _.:,~_. ~ _" - ~"-. .. - .' .. ~.-- - ---~----.-,--~-.-....

ing and optical micrometer reading, as read directly from the left to right. Fig. 14(a) is read 90°15'6", in the case of the Model

TL-6DE. (a') is read 135.552g, in the case of the Model

Fig. 14 (a) TL-6DE.

..

II

90

Fig. 14 (b) is also read 135°]'0", in the case of the Model TL-10DE.

(b') is also read 135.530g, in the case of the Fig. 14 (b) Model TL-10DE.

(b')

·....:....

,

·1

Fig. 14 (c) is read 135°7'0", in the case of the Model TL-20DE (TL-20DEP).

(c') is re<;ld 135J~29, in the case of the Mooel TL-20DE (TL-20DEP).

Fig. 14{c} (c i )

13. Vertical Circle Reading The vertical circle is also graduated and numbered in one degree divisions. with the values increasing from 0 to 359

0 or 399g. when the telescope is rotated in the clock­

wise direction. as seen from the left standard side of the instrument. The numbers and single graduation lines appear in the vertical circle frame which is marked V. Therefore, re­volve the optical micrometer knob and. center the single liDe within the d.o.vple in~~x~lin:~:TWe. ~eadi~g:.rnthis case, can also be read directly from the left to the right.

Fig. 15 (a) is read 86°5'36", in the case of the Model TL-60E.

(a') is read 80. 552g, in the case of the Model TL-6DE.

Fig. 15 (a) (a')

Fig. 15(b) is read 279°17'10", in the case of the Model . TL-10DE.

(b') is read 80.530g, in the case of the Model TL­WOE.

Fig. 15 (b) (b')

Measuring angles by using a theodolite is obtained by the following steps:

1- Setting up the theodolite on the vertex of the angle to be measured. 2- Leveling the theodolite by centralizing the bubble. 3- When the theodolite is exactly set over a survey mark and properly leveled, it

can be used in two positions namely:

(a) Face left or circle left. . (b) Face right or cirde right.

The instrument is said to be facing left when the vertical circle is ontheobservet!s left, and said to be facing right when the vertical circle is on his right.

4- The angle is to be measured by turningilie.instrument to the first edge of the angle and taking the reading, then turning it to the next edge and taking the reading, after that subtract the two readings to get the value of the angle.

\ esc '-:c' "".'=.' \ u , •

V

Group No.. ------­

L

2.

4.

5.

6.

7.

8.

9.

10. ------------------------------------­

Surveying Lab

Level General Knowledge

stoff level '.,

\..It,

.Iine Q·f 1 t­

Surveying Lab

Level General Knowledge

After this laboratory, the. student should be able to set the horizontality of the instrument & take a staff reading.

level ! '.. 'II' "

lioe {!: ~ CO!UnntIOf'l

B 2.500

.

. "" ..

I ,

I A 95.1.00

Ordnm.c€ dotom

1- The staff holder holds the staff on the mark and ensures that it is..held perfectly vertically facing towards the instrument.

2- The observer directs the telescope towards the staffand using the focusif.l:g screw on the side of the telescope brings the staff clearly into focus then take the reading.

I 0

/1Jg<~\! t \\{ I o. J .1-',<'r T-l8:.~-·II'····· .----.-] \ ] I .f ;.. ,. '-::".~-::..'" !\. I -. - o· -'1'".... ~.J'''w,/'

" I O· I ./-"-..1 0 1./

r~"~~----+_/

~13 •

!

1)- Find the reduced levels of the given points and Apply a full arithmetic check.

Given that the RL of point.. .... is ( ...... )

Pts Staff Readings Rls Remarks B.S LS F.S

.­ ':"

-.­

Group No.

Group Names:

1.

2. -, .J.

4.

5.

6.

7.

8.

9.

10. ------------------------------------­

Surveying Lab

Level Determination of Road Center Line Profile

1- The instrument is set up approximately midway between the points.

2- The instrument is to be accurately leveled.

3- The r:eadlngsare ta.k~fi'ftOni thestaf(s· at .diffeF~ntpositi0ns from the road ( outer"edge, ~imlt7r:"eitge ancieetlterlineot tlieroad)'.

4- Levels are calculated at the different positions ofthe road.

5- The road profile is plotted and the (longitudinal I side) slopes are calculated.

1)- Find the reduced levels of the given points and Apply a full arithmetic check.

Given that the RL of point.. ... .is C.. ... )

, Pts Staff Readings Rls B.S I.S F.S

Remarks

Group No.. ------­

Group Names:

L

2 . ... .J.

4.

5.

6.

7.

8.

9.

10. ------------------------------------­

-,

Surveying Lab

Grid Leveling

L -­"e",80

.. ,~,.SJ - '-8.55 RL£ A~

..... - .--~-~

~- -­ -,----..: -9.00­

c

60

- -··-!iJOm --'---'---'-r

alan, _ Xy

Surveying Lab

Grid Leveling

1- The site is to be divided into a grid of squares.

2- The instrument is set up approximately midway between the points.

3- The instrument is to be accurately leveled.

4- The readings are taken from the staffs at each node of the grid.

, 5- Levels are calculated at each nOde.

6- A contour map is plotted using the calculated levels.

r

."

"

~"..\, .-.---... - -+._....,

._...-} t -.~ ..

:; .1.-";,.::....____ ._ .. ____________.•

1)- Find the reduced levels of the given points and Apply a full arithmetic check.

Given that the RL of point. _. _.. is (. _____ )

-~~...

- Pts Staff Readings Rls B.S LS F.S

f------­

F_ -

.

Remarks

' .... ".: ....