METHOD STATEMENT FOR ESTABLISHMENT OF PERMANENT BENCHMARK SYSTEM

The purpose of this Method Statement is to describe the methodology for structural work of METHOD STATEMENT FOR ESTABLISHMENT OF PERMANENT BENCHMARK SYSTEM and to details out the steps to be taken in meeting the technical requirements of Van Phong 1 thermal power plant project.

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PERMANENT BENCHMARK SYSTEM

Document Type For Information

Document No

VP1-0-L4-C-GEN-10018

monitoring work Please refer reversion B

23/03/2020 O

3 11 23/03/2020

Is it license software?

QCVN and TCVN did not specific provisions So

it has not license The reversion B added more Hhmaps soltware

23/03/2020 O

23/03/2020 Due to impact of external factor during construction, please supplement the schedule of measuring cycle until shut settlement (stabilization settlement) of benchmark

Stability of permanent benchmark shall be check with 6 months for one time

23/03/2020 O

Closed

Closed

Not agree, Codes is not related to software silence

OPEN

- Please supplement schedule for this activity so that we can follow up

- Frequency at beginning time should

be 1 month; then it will be reduce base on the stability of benchmark

- Kindly be informed that the report and its procedure may be reviewed by National Acceptance Committee in future.

be unified So the original data supply sheet in

document No:

VP1-0-L4-C-GEN-00002_Topographic&Bathymetric Report(Rev.C) shall be reuse other survey report

That is one of Sub-suppliers of Him Lam 23/03/2020 O

Additional Notes (if any)

* O - Open, C – Closed

Closed

Closed

Doosan Heavy Industries and Construction

EPC DOCUMENT No

Information acknowledged with no comment

Information acknowledged with comments Note: Approval or comment does not relieve the Contractor of

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Table of Contents

1 PREFACE - 3

2 CODE - 3

3 DATUM - 3

4 ORIGINAL DATA OF NATIONAL BENCHMARK - 3

5 VOLUM OF WORK - 5

6 SURVEY EQUIPMENT AND MANPOWER - 5

6.1 SURVEY EQUIPMENT - 5

6.2 MANPOWER - 6

7 METHOD - 6

7.1 BUILD PERMANENT BENCHMARK SYTEM - 6

7.2 HORIZOTAL CONTROL NETWORK - 10

7.3 VERTICAL CONTROL NETWORK - 11

7.4 STABILITY OF PERMANENT BENCHMARK SYSTEM - 11

8 APENDIX - 13

8.1 SUPPLY SHEET OF NATIONAL BENCH MARK - 13

8.2 CERTIFICATE OF GPS EQUIPMENT - 15

8.3 CERTIFICATE OF TOTAL STATION AND LEVEL MACHINE - 16

8.4 CERTIFICATE OF MANPOWER - 20

EPC

Doosan Heavy Industries and Construction

VP1-0-L4-C-GEN-10018 B

3

1 PREFACE

- Plant Project: Van Phong 1 Thermal Power Plant

- Company/Owner: VAN PHONG 1 POWER COMPANY LIMITED

- Consultant:PÖYRY SWITZERLAND LTD

- Contractor: IHI–TESSC–CTCI–DHI CONSORTIUM

- Ninh Hoa town is the coastal plain of South-Central Vietnam, in Khanh Hoa province,

located to the east of the North-South arc of the Truong Son range on the coordinates from

12020 '- 12045' North Latitude and from 105o52 '- 109o20' East Van Phong 1 Coal Fire

Power Project (VP1) Which is project level 1 of National

- The purpose of this Method Statement (MS) is to describe establishment permanent

benchmark system for Construction progress and Settlement & Tilt monitoring works at VP1

2 CODE

- QCVN 04: 2009/BTNMT National technical regulation on establishment horizontal control network

- QCVN 11: 2008/BTNMT National technical regulation on establishment vertical control network

- Vietnamese standard No.: TCVN 9398:2012 Surveying in construction -General

requirements

- Vietnamese standard No.: TCVN 9401:2012 Technical of measuring and processing GPS data

in engineering survey

- Vietnamese standard No.: TCVN 9360:2012 Technical process of settlement monitoring of

civil and industrial building by geometrical levelling

- Vietnamese standard No.: QCVN 11:2008/BTNMT National technical regulation on

establishment of leveling network

- VP1-0-L4-C-GEN-00002_Topographic&Bathymetric Report (Rev C)

3 DATUM

- Horizontal datum: VN-2000 coordinate system, 108°15’ central meridian, 0.9999 scale factor

- Vertical datum: Hon Dau – Hai Phong vertical datum

4 ORIGINAL DATA OF NATIONAL BENCHMARK

- Based on TCVN 9398:2012 The establishment permanent benchmark use Grade III for

horizontal control network and Grade I for vertical control network

- Original data: We will use 2 or 3 National Coordinate Benchmarks: 923428, 923430, 923445

These are grade III and one National leveling benchmark is grade I

- The information details of these points (3nos) attached in the report of the appendix for this

MS to be described follow in tables below:

B

Table 2: Original data (National Bench Mark) for vertical control network

< Location of National Bench Marks on Google Map >

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5 VOLUM OF WORK

- Based on TCVN and the requirement at the site The horizontal control network will be

established, which have 4 points in first time and by GPS, Total station method and 3 points more

in second time by Total station method

- The vertical control network will be established with 7 points by geometrical levelling method

- All permanent benchmark will be connected to National Benchmark (Vertical & Horizontal)

Table 3: Quantity for vertical control network at site

1 The horizontal control network Point 7 Accuracy equivalent as Grade III

- Equipment will use to establishing horizontal and vertical control network, those will be satisfied

to technical and certificate

- The certificate – calibration – verification was attached in the appendix

Table 4: Survey equipment.

※ Certificates of Equipment are attached at Appendix 8.2

B

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6.2.MANPOWER

Table 5: List manpower for survey work

※ Certificates of Engineers are attached at Appendix 8.3

7 METHOD

7.1.BUILDING PERMANENT BENCHMARK SYTEM

- Benchmark will be put on hard rock or on test pile The stabilisation of these will be

guaranteed during construction time

- Benchmarks are cocrete block with dimention 1,2m x 1,2m x 1.3m These follow type 1 and

type 2 as drawing below:

B

7

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Benchmark structure

- Locations for benchmarks are as the drawing below, PBM-1 ~ PBM-4 follow type 1 and PBM-5 ~ PBM-7 follow type 2

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Benchmark Location

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7.2 HORIZOTAL CONTROL NETWORK

- The horizotal control network will be established by GPS method, 5 GPS equiment are set on

923428, 923430, 923445 and PBM-1 ~ PBM-4 within 2 hours to best receive signal from satellites

- The GPS’s result will be adjusted by software (Trimble Business Center) and checked again by

Total station method

- Accuracy of horizotal control network follow TCVN 9398 : 2012 The accuracy equivalent will be

as Grade III landmark network The GPS’s result after adjustment will be used such basic data to set

up PBM-5 ~ PBM-7 by Total station method

- The diagram for checking GPS as below:

Diagram for checking GPS

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network The technical regulation with Grade III as table below:

Table 6: Technical regulation of Grade III for Horizontal control network

Position error maximum

III

7cm

7.3 VERTICAL CONTROL NETWORK

- The vertical control network will be established by geometrical levelling method The result will be

adjusted by software HHmaps or DP Survey

- Accuracy of horizotal control network follow TCVN 9398 : 2012 Thes Accuracy equivalent will

be Grade IV levelling network

- The diagram for measurement levelling as route :

Line 1: I(VL-HT)157 PBM-1 PBM-2 PBM-3 PBM-4 PBM-5 PBM-6

PBM-7 I(VL-HT)157

- Based on QCVN 11: 2008/BTNMT National technical regulation on establishment vertical control

network The technical regulation with Grade IV as table below:

Table 7: Technical regulation of Grade IV for Vertical control network

Region Grade Closure Error of measuring

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7.4 STABILITY OF PERMANENT BENMARK SYSTEM

- Stability of permanent benchmark system will be checked by every 6 months in construction process and before each cycle for monitoring process until shut settlement

- Checking Benchmarks will be cross-check for each bench marks

- The horizontal displacement of them will be checked by Total station with measurement side & angular

- The settlement will be checked by level machine Based on the result (length side,angular and difference heigh) to compared last cycle to review stability of PBM system

B

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8.1 SUPPLY SHEET OF NATIONAL BENCHMARK

The Data of National benchmark is public ownership and to accuracy construction process be unified

So the original data supply sheet in document No:

VP1-0-L4-C-GEN-00002_Topographic&Bathymetric Report (Rev.C) will be reuse other survey report. B

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15

B

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CERTIFICATE OF TOTAL STATION AND LEVEL MACHINE

17

18

19

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8.3.CERTIFICATE OF MANPOWER

B

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