POS MS FS a1 EN

Plan Drawing of Topographic Survey --- 157 Base Points : point that will be used as a base, GPS Point, Control Point, Construction Point can be a Base Point Control Points : point that

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IV Plan Drawing of Topographic Survey - 157

Base Point(s) : point that will be used as a base, GPS Point, Control Point,

Construction Point can be a Base Point

Control Point(s) : point that will be used for setting road centerline, pier centerline,

and Construction Point

Construction Point(s): point that will be used for construction works such as bored pile,

substructure, superstructure, bridge surface, and embankmentworks This point will be set out from Control Points

GPS03B, GPS04B, GPS06, GPS07, GPS08 and GPS09

Total Station : a surveying instrument that can measure azimuth angle and

distance

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2) Setting Out Construction Points

3) Field Survey for Construction Work

4) Topographic Survey

The minimum surveying personnel per one team is as bellow:

3 Setting Out of Control Points

3.1 General

Control Points will be used as Base Points for setting out center of road, center of piers,center of structure, and Construction Points Control Points will be set out using GPS Pointsgiven by the Employer And GPS Points themselves are used as Control Points Refer toNetwork of Control Points (See Appendix I)

Control Points newly set will have data of coordinates (N, E) and elevation as well

3.2

Accuracy of Field Survey

Accuracy of the survey work applied shall be accordance with the general specificatios of the contract by the following table:

Construction Surveying and Staking Tolerances

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slope stake references (b

Note: (a) Center line points are point of curve (PC), point of tangent (PT) and point on curve (POC) (b) Take the cross sections normal to the centerline within ±1 degree (0.02 rad).

be proposed in the report of Control Point Network Survey, if necessary

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not to be submerged during rainy season

In addition, Control Points will be set on top of each pier after the erection work wasfinished Basically, the structure of Control Points is in accordance with Highway SurveyCodes 22TCN263-2000; however, 4 types of structure as below will be adopted consideringthe ground condition or surroundings

submerged

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10 75

CERAMIC MARKER

200 300

Control Points (Type 4) on top of piers and on the surface of the structures will be set on thecenter of it or on parallel line of that center line Each of the Control Points will be drawn by

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3.3.2 Procedure

Procedure for setting out on land is as follows

1 Reconnaissance, location selection for Control Points

2 Setting out stakes made of wood

3 Confirmation that the sight has no problem with using transit

4 Setting out points (casting concrete or stage erection by block as shown in fig 1)

5 Execute triangulation or traverse survey using Total Station

6 Decision of coordinates for each Control Point

7 Elevation survey

8 Decision of elevation for each Control Point

Procedure for setting out on pier is as follows

Points on pier will be on the centerline of structure

1 In case of the first Control Points setting on pier, or in case of no Control Points on pierare not available, new Control Points will be set out by using 2 original Control Points

2 In case that there is available Control Points on pier, new Control Points will be set byusing that Control Points After that, set the Total Station on the new Control Point, thedistance and angle of the Control Points on land will be used for checking and set thecenterline of structure as base line

In case that Control Points are set after completion of pier erection, it will be confirmed asfollows

by Steel Measuring Tape

far Control Point on centerline of structure, then Control Points among these 2Control Points will be confirmed whether they are on structure centerline or not.c) If the results of a) and b) is good enough, structure centerline will be drawn on thefront and top of nearest pier Right angle direction will be drawn on the top of

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b) Checking by field survey

Control Points will be checked at once per 6 months or at the time of Engineer’sinstruction by traverse survey and/or triangulation method The period is March andSeptember after rainy season ends The method of survey is same as setting ControlPoints and Control Points on bridge structure will be checked as well

Relaxation of foundation will be checked especially after rain season ends If there is aControl Point that cannot be utilized any more, new Control Point will be set out again

4 Setting Out of Construction Points

4.1 General

Construction Points are utilized for actual construction work such as bored pile, cofferdam,pile cap, pier, superstructure, embankment and work for roads and bridge surface.Construction Points will be set out based from Control Points

4.2 Accuracy of Field Survey

Accuracy for Construction Points is same as those of Control Points

4.3 Setting out Work

4.3.1 Method

Construction Points will be set out from Control Points including GPS Points First of all,Base Line will be set using Control Points and field survey for setting out ConstructionPoints will be executed based on the Base Line using Total Station

During the setting out work for Construction Points, checking will be done as follows.a) Confirmation will be done using other Base Line

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Location of Construction Points will be selected as the following for each works:

Stiff Ground, and the points where no heavy equipment working during constructionworks Offset points those are used for check piling work, excavation, cofferdam work,pile cap construction, pier erection, and road works will be set out

Bridge Surface Work

Construction Points will be set on the top of girder completed with checking fromControl Points on the ground and on pier

4.3.3 Checking

Construction Points will be checked when using Each Construction Points will be arranged

on a line; therefore, straightness will be checked from any Construction Points Ifdisplacement is found, the Construction Point will not be used, and new Construction Pointwill be set out again

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5 Field Survey for Construction Works

In this section, methods of field survey are stated for each construction works as shown below

5.1 Bridge works

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Procedure of survey work for bored pile work is as follows.

PILE ARRANGEMENT

LC R-PIER L-PIER FRONT VIEW

PILE ARRANGEMENT

SIDE VIEW

1 : Setting out Construction Point 7cmx7cm, wooden stakes.

2 : Setting out Offset Stakes from 7cmx7cm,wooden stakes.

3 : Setting out Pile center from X 3cmx3cm, wooden stakes.

4 : Check by the Engineer.

5 : If it is no more available, re-set out from X.

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2) Excavation

Procedure of survey work for excavation is as follows

PILE ARRANGEMENT

SIDE VIEW

1 : Setting out Offset Stakes from 7cmx7cm,wooden stakes.

2 : Setting out Excavation line from X 3cmx3cm, wooden stakes.

3 : Setting out Offset point from 7cmx7cm, wooden stakes.

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3) Pile Cap

Procedure for execution of pile cap work is as follows

PILE ARRANGEMENT

PLAN VIEW

SIDE VIEW

1 : Setting out Offset Stakes from O 7cmx7cm,wooden stakes.

2 : Marking out by setting Total Station at X.

3 : Marking Pile cap line from .

4 : Marking out Structural and cross-section centerline Offsetting from using steel measuring tape.

Wooden Stakes X will be removed after No 2 ends.

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4) Pier (at Base)

Procedure for execution of pier column work is as follows

LC R-PIER L-PIER FRONT VIEW SIDE VIEW

PLAN VIEW

1 : Setting out Offset Stakes from O 7cmx7cm,wooden stakes.

2 : Marking out by setting Total Station at

3 : Marking out Structural and cross-section centerline setting Total Station at .

4 : Marking out pier line based on the line drawn by No 3.

5 : Offsetting pier line 30cm far from Pier line.

Wooden Stakes will be removed after No 2 ends.

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5) Pier (at Top)

Procedure for execution of pier column work is as follows

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Plan View

End Point of Girder

Side Line of Girder

End Point of Girder

Position of Marking on Bridge Seat

Cross Section

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5.2 Underpass works

5.2.1 Substructure

1) ExcavationProcedure of survey work for excavation is as follows

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Procedure of survey work for Bottom Slap is as follows.

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Set out design center of pier: Straightness and vertical will be check based on

the offset line of pier line maked out, cheking will execute using Plumb that will

be hanged from the top of column from

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6 Topographic Survey

6.1 General

Topographic Survey will be executed for 3 purposes as follows

by excavation and/or Embankment

made with using cross-sectional drawing and longitudinal profile drawing

6.2 Positions to be surveyed

Two (2) kinds of field survey will be executed for topographic survey Those are cross-section

of road and bridge position and longitudinal profile of road and bridge position Positions to besurveyed are shown in Drawing below

Additional cross-sections is requested at significant breaks in topography and at changes

in the typical section (point of tangent (PT) and point middle curve (MC)) For eachcross-section, rod points shall be measured and recorded at changeable topography withmaximum 5m-interval between rod points

The width of cross section is area between approximately 20m offset line of both sides ofland acquition Points to be surveyed are as following drawing

PT

MC

PT

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2) Longitudinal Profile of Road and Bridge Position

Considering the project area, through way center, frontage road, & ramp center line will

be surveyed Longitudinal profile at center line of box culvert and pipe culvert shall besurveyed also

Distance and elevation will be surveyed using Total Station

Before starting Topographic Survey, road and bridge center line shall be marked by stakes atsite Method of setting out, coordinate and location drawing of each center point are stated asfollows

6.5.1 Site Organization Chart

Fig 1 For Bridge Section Fig 2 For Embankment Area

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6.5.2 Topographic Survey Sections

Topographic Survey Sections are proposed according to the method shown below

Site Manager

Project ManagerConstruction Manager

POSCO E&C Co., Ltd.

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appropriate position (as shown in Fig.2) In the case that Frontage road is straightline,parallel adjacent with to Throughway, shall be set only one cross-section (as shown inFig.3).

To carry out Topographic Survey, total station shall be set at any location After setting totalstation at certain location, coordinate of this location will be checked by 2 known ControlPoints Then, both boundary and other several points on certain Topographic Survey sectionwill be marked by stakes or bamboo poles and Topographic Survey section line will bemarked by some rope or measuring tape Along this marked line, coordinate and elevation of

Center of Throughway L.A.B

Topographic Survey Boundary

20m 20m

Fig 1 Topographic Survey Section Width (Throughway)

Center of Throughway L.A.B

Topographic Survey Boundary 20m

Fig 2 Topographic Survey Section Width (Throughway with Ramp Way)

L.A.B 20m Center of Ramp Way

L.A.B: Land Acquisition Border

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6.5.3 Longitudinal Profiles

Longitudinal Profiles of road, bridge, underpass, box culvert and pipe culvert will be surveyed at the longitudinal center line of each structure Structures of which longitudinal profile will be surveyed are listed below

Underpass Box Culvert:

No Station Road Class

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Drainage Box Culverts:

No Station Function

Irrigation Pile Culverts:

No Station No Station No Station

N

o Station Function Km

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5 Km 1+285 25 Km 8+620 45

Km 14+635 65 Km 20+100 Irrigation

6 Km 1+340 26 Km 8+799 46

7 Km 1+522 27 Km 8+860 47

8 Km 2+280 28 Km 9+488 48

9 Km 2+370 29 Km 9+743 49

10 Km 2+494 30 Km 9+805 50

11 Km 2+600 31 Km 10+010 51

12 Km 2+855 32 Km 10+190 52

13 Km 2+887 33 Km 10+485 53

14 Km 2+991 34 Km 10+880 54

15 Km 3+305 35 Km 11+193 55

16 Km 3+555 36 Km 11+640 56

17 Km 4+010 37 Km 11+827 57

18 Km 5+665 38 Km 11+925 58

19 Km 5+787 39 Km 12+290 59

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A2 Km 01+430 Drainage

D Km 01+010 Irrigation

Culverts at Interchange No.4:

No Station Function A1 Km 00+760 Drainage A1 Km 01+840 Drainage

Center points will be set out prior to Topographic Survey and used for this survey work

b) Accuracy of Field Survey

Accuracy for Center Points is same as those of Control Points

c) Setting out Work

 Method

Center Points will be set out from Control Points including GPS Points First of all, BaseLine will be set using Control Points and field survey for setting out Center Points will beexecuted based on the Base Line using Total Station After coordinate of Center Point is

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Location of Center Points of Embankment and Bridges will be selected as the following foreach works:

Center Point coordinates are included in attached table of Appendix III And also According

to these coordinates, Center Points will be set out

6.6.5 Inspection

Topographic Survey shall be done in the presence of Inspector Proposed Inspection Sheet is

Topographic Section shall be recorded and sign by Inspector Coordinate and elevation ofsurveyed point shall be taken from total station in office and submitted with this Inspectionsheet for approval later

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7 Method of Field Survey and Apparatus

7.1 Apparatus

Total Stations and Auto-Level will be nominated as equipments used for Field Survey work These equipment may change provided by the Sub-contractor when working

The Certificates of Survey Equipment are attached as Appendix VI

7.2 Calibration

Checking apparatus is executed once a month by the Contractor under the supervision ofthe Engineer In addition, checking apparatus is executed once a year by third party inorder to get calibration certificate to confirm the quality of apparatus The result includingchecking person and/or organization and date of checking will be recorded and submitted

to the Engineer.If the error is over the tolerance, the apparatus will be sent for repair

-Transit

3 points will be set on a line by 100m distance between each point Setting transit atthe center point, and the angle of 180°will be checked with turning over the sight -

Total Station

Setting of Total Station at the Base Point of GPS Point (GPS01, GPS02,… GPS09) oneControl Point coordinates will be checked based on a Base Line of GPS Point –Control Point on a known Bench mark

-Level

2 points will be set in line, and elevation survey will be executed from the middle point

of the 2 points and from near the one point Confirmation will be made by checking

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4) The calculated result must be within the range of the following allowabletolerances.

not more than 8”

be < 1/70,000 in which S is length of side

7.4 Field Survey Using Level

The elevation transverse should be measured in both the forward and backward direction toform in one closed system The best distance from the level to the leveling staff is 75m, butthis distance could be extended to 100m if a good picture is provided The height of thesurvey ray should be at least 0.3m above the ground or any object

The difference of distance from the level to the leveling staff should not be more than 2mand accumulative distance differences within one section should not be more than 5m

7.5 Documents to be submitted

8 Survey Points to be Used

Those coordinates and elevations are shown below Before using these points, they shall bechecked by GPS

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