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Mapa Institute of Technology -Intramuros
School of Civil, Environmental, and Geological Engineering
Advanced Surveyingield Manual
C!"#SE A$% SECTI!$& CE'(')*(
Submitted By:
CABARCE, Christian Angel C. Student No. 2012107!0
"rou# No. 1 Chie$ o$ %arty:
&ate o$ 'ield (or): 10**201+ &ate o$ Submission: 10**201+
Submitted o:
IE+% !# $!./+aying of a Simple Curve !n "neven Ground "sing Transit
and Theodolite 0%ou1le-%e2ection Angle Method3
"RA&E
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%ro$essor Engr. -alerie ra Balmoris
ntrodu/tion:
An automatic level is an optical instrument used to establish or check
points in the same horizontal plane along with a vertical staf to measure
elevation diference in elevations, etc. When it comes to surveying, automatic
levels are the most widely used tool in inspecting elevations in a site.
For Diferential Leveling With urning !oints "Double #odded$, like the
previous %eldwork, students are e&pected to practice the basics o' surveying by
using the precise level and the leveling rod to know the diference in elevations.
he students must locate their ()*+ on the %eld then %ve urning !oints which
o' the same distance to each other. ach o' these %ve turning points have their
higher ground and lower ground, with a total number o' ten turning points "both
low and high$. At the end, they must locate the ()*-, which will be the end o'
the course. (acksights are 'oresights are still needed to be 'ound, however, the
'oresight 'or ()*+ is disregarded in this %eldwork and wont be needed.
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be/ties and nstruments:
be/ties
+. o be able to lay a simple curve on uneven ground.-. o be able to lay a simple curve using double*de/ection angle method.0. o master the use o' the transit and theodolite in laying a simple curve.
nstruments
* - #ange !oles* 12m ape* 3halk
* + ransit * + heodolite
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An instrument similar to anordinary surveyor4s levelbut capableo' %ner readings and including aprismarrangementthatpermitssimultaneous observationo' the rod and the levelin bubble.
Leveling rod is e5uipment that ties wi
precise level. 6t is a long rod thameasure marks, usually in termmillimeters. he rod can be e&tended, widely used in measuring the diferenelevation.
3halks were used to mark points A and(. 3halks are typical markers on the%eld.
!lum bob is suspended 'rom a string andused as a vertical re'erence line. 6n the%eldwork, this used to ensure the center o'the dumpy level is in line with themarkings on the ground.
http://www.dictionaryofconstruction.com/definition/surveyor-s-level.htmlhttp://www.dictionaryofconstruction.com/definition/permit.htmlhttp://www.dictionaryofconstruction.com/definition/leveling.htmlhttp://www.dictionaryofconstruction.com/definition/bubble.htmlhttp://www.dictionaryofconstruction.com/definition/permit.htmlhttp://www.dictionaryofconstruction.com/definition/leveling.htmlhttp://www.dictionaryofconstruction.com/definition/bubble.htmlhttp://www.dictionaryofconstruction.com/definition/surveyor-s-level.html -
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--
3 %ro/edures and Com#utations:-
+. he pro'essor gives the 'ollowing data7
* d1 8 9999999: D 8 9999999: d
2 8 9999999: Location o' !3 on the site* Azimuth o' the backward tangent 8 999999999: Adopt Full chord length o' 999999 m
* ;6 ?D > d2
8 9999999999
* =@7 (e very care'ul in assigning the location o' !3 and the direction o' the
backward tangent so that the curve will not be obstructed by any structure.*
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+E. ERROR=|Computed Chord LengthMeasuredChord LengthComputed Chord Length |100+1.
'4.
'5. I$A+ %ATA S6EET
1.'E4& (R5 ! '7.+A8I$G ! A SIM9+E C"#:E !$ "$E:E$
G#!"$% "SI$G T#A$SIT A$% T6E!%!+ITE
0%!"*+E-%E+ECTI!$ A$G+E MET6!%320.&AE: @3@(# ,
-2+1
-+. "R6% N.
22.E: 2!.4CAN:
28.(EA9ER: 2+.%R'ESSR: =;#.
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! ! F
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A. Computations
cd.or lo;er ground&
ce. BM1's HI=2.131m+0m
cf. TP1L's Elev=2.131m2.075m
cg. TP1L' s HI=2.205m+0.056m
ch. TP2L' s Elev=2.261m2.192m
ci. TP2L' s HI=2.197 m+0.069m
c
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de. BM2H's Elev=2.517m2.394m=0.123m
*. S=etchdf.
dg.
dh. "A panoramic view o' the site where the %eldwork was done$di.dI.
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The BM-1 was located on this part, which is othe far right on the panorama.
BM-1
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BM-2
The turning points assigned were at locations inbetween 2 slopes. Turning point 1 H will be locatedon a higher ground, while 1 L will be on the lowerground. They must be euidistant to each other.
!ame as the pre"ious #eldwor$, %f wewere to describe what could be seen inthe precise le"el&s telescope, thepicture to the left is e'actly therepresentation of what can be seen.
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e#.
e.er.es.et.
eu.e.e;.e.$g.$h.?.$.$).@.
$m. Signature o$Student
$n. Resear/h and &is/ussion:
The bac$sights and foresights must beta$en then mo"e to another station.(ntil it reaches the BM-2, that is whenthe course is complete. The ele"ationand H% will be sol"ed through formulas.
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'o.
'p.
'5. 3@=3! B !#6=36!L7
'r.
fs. he same 'or the previous %eldwork, we shall still de%ne some terms
known in this %eldwork.The term le"el is used compare the relati"e position of an
ob)ect with the hori*on or the relati"e position of two or more ob)ects. +b)ects
that are le"el are parallel with the hori*on and at the same ele"ation with each
other. Le"el is usually determined by an air bubble in a small container of liuid.
The container is usually either a tube or cylinder.This apparatus is commonly
called a spirit le"el or simply a le"el. The spirit le"el by itself is not a useable tool.
%t is usually incorporated with additional tools, for e'ample, a carpenters le"el, or
a sur"ey le"el. +b)ects are also le"el if they are perpendicular to a "ertical line.
"ertical line can be established with a plumb bob or a piece of string with a
weight.
't. he term benchmark originates 'rom the chiseled horizontal marks that surveyors
made in stone structures, into which an angle*iron could be placed to 'orm a KbenchK 'or a
leveling rod, thus ensuring that a leveling rod could be accurately repositioned in the same
place in 'uture. hese marks were usually indicated with a chiseled arrow below the horizontal
line. he height o' a benchmark is calculated relative to the heights o' nearby benchmarks in a
network e&tending 'rom a 'undamental benchmark, a point with a precisely known relationship
to the level datum o' the area, typically mean sea level. he position and height o' each
benchmark is shown on large*scale map.
fu.
f". dierence in ele"ation is the "ertical distance between two le"el surfaces or
planes. %f the ele"ation of each of the le"el surfaces is $nown, then a dierence in ele"ation
could be calculated between the earth and ele"ation or either surface and also between any two
surfaces.
fw.
f'. bac$ sight is a rod reading ta$en on a point of $nown or assumed ele"ation. The
ele"ation of a point would be $nown if the true ele"ation abo"e sea le"el were $nown. The
ele"ation would be assumed if it was a local benchmar$ where the true ele"ation was not
$nown.
fy.
f*. foresight is a rod reading ta$en on a point of un$nown ele"ation. %n sur"eying
two dierent types of foresights are used, intermediate,and true. n intermediate foresight is
a rod reading on a point that will not be used as a turning point or benchmar$. true foresight is
a rod reading on an un$nown point that will be used for a turning point or for a benchmar$.
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ga.
gb. turning point T/0 is a station along a sur"ey that is established as a temporary
benchmar$. The purpose of the turning point is to pro"ide a new reference point when the
instrument is mo"ed. The turning point should be a sta$e or other durable structure and the
ele"ation should not be part of the sur"ey data. The instrument would be set up at instrument
position one %/10 a bac$ sight would be ta$en on bench mar$ one BM10 and foresight on the
turning point. +nce the bac$ sight and foresight rod readings are $nown, the ele"ation of the
turning point can be computed. The T/ becomes a new point that can be used as a reference
point. %t is not considered a bench mar$s unless the appropriate mar$er is used. Turning points
are intended to be temporary. Then the instrument would be mo"ed to %/2, and the process
repeated until the second benchmar$ was reached.
gc.
gd. #LA6@= @ @C# @!637
ge. his and the previous %eldwork can be tied with the two*peg test.
=ormally, a two*peg test is a kind o' test wherein you determine the error o' a
level and to provide necessary adIustments to calculations. 6t is also a
recalibration process 'or the level to obtain accurate readings on a level.
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g5.
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gy.g=.ha.hb.h/. Con/lusion:hd.
he. As said in the previous %eldwork, it is important to know the basics o' leveling
since its one o' the 'undamentals o' surveying. Aside 'rom the measuring,
knowing the elevation is important mostly in the %eld to have an accurate survey
o' the land to be taken.
h'. 6n comparison with the sources o' error with the previous %eldwork and to this
current %eldwork, we can say they have similar sources o' error. 6' the levels
bubble is not in the center, this would make the level not balanced and would
have increments in readings than a normal reading would. Another error happens
when the leveling rod is not straight, this afects the readings on the level
because the accuracy o' the reading must be, normally, in millimeters and with
that said every inaccurate slanting o sudden movements 'rom le't to right afects
the whole reading. Another source o' error is when about to touch or trip the
tripod, which imbalances the level because movements misalign the bubble o'
the level. he leveling stafs bottom part must be clean since any organic thing
that is on the staf could afect the reading to be taken.
hg. 3ommon recommendations can be suggested to make the %eldwork really
easy and to obtain the most accurate way. Cere are some recommendations7
hh.
hi. WA
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hl. !A36=;
hm. Like the previous %eldwork, measuring tapes were not provided 'or
this %eldwork. 6n order to maintain e5uidistant lengths 'or each turning point, etc.
!acing is a good substitute 'or measurements.
hn.
ho. (ALA=36=; C (N((L
hp. here is a techni5ue to easily place the bubble to the center. here are 0leveling screws on the telescope. 6n order to balance the bubble, the telescopes
a&is must be parallel and in*between the two leveling screws. A'terwards, we
must turn the two leveling screws both in or both out, never o' the same
direction, to bring the bubble adIacent to the center. A'ter this, use the third
leveling screw to place the bubble to the center.
h5.
hr. W@*!;
hs. his test is also applicable 'or the %rst %eldwork that uses the level. Why
two*peg tests are help'ul anywayM As stated, two*peg tests are like recalibration
process 'or a level to know what is the error o' the level itsel'. #eason behind this
is that when a level is used, you are not really sure, despite you leveled the
bubble correctly and such, whether the level reading itsel' has an error. Nsually,
surveyors used two peg*test to check 'or the error i' in case it was dropped, etc.
he acceptable error is usually - millimeters over + meters.
ht.
hu. ome other tips to easily %nish the %eldwork is to minimalize all
unimportant acts during %eldwork, such as not placing your entire hand that
covers the graduations o' the level rodB staf. Also, avoiding tripping the tripod
that will imbalance the bubble in the bulls eye level. Another recommendation is
using a Field book "6t can be a simple notebook, etc.$, aside 'rom the data sheet
given, so that it will be easy to place all data that have been gathered.
Additionally, doing the two*peg tests as stated in the previous paragraph, helps
the accuracy o' the readings.
hv. For the application o' this %eldwork, it is still the same 'rom the previous
%eldwork, an application in %eld could be making a contour plan. With contour
plans, we can determine the slope o' the land, /oor levels, etc. hese things areimportant because they are pre*re5uisites be'ore doing the main construction on
a speci%c site.
hw.
h&.
hy.
h=. Re$eren/es:ia.
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ib. Waving the #od Forwards and (ackwards, (alancing the (ubble and wo*
!eg est: 'rom @= (uilding 3ourses
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