02 ms geological survey a2 en

ĐỀ CƯƠNG GRBCC Noi Bai Lao Cai Highway Construction Project Package A7 Km190+420 ~Km 218+040 Method Statement for Geological Survey GRBCC MS GEOSURV A2 EN CONTENTS 1 General view 2 1 1 General introdu[.]

1 General view - 2

1.1 General introduction

1.2 The aim of survey: 1.3 Codes and Standards for Survey and Design: 2 Additional Geological Survey - 2

2.1 Plan of borehole position and anticipated volume

2.2 Content of Geological Survey 3 Construction Schedule - 7

4 Site Organization Chart - 7

5 Machine and Equipment - 7

6 Construction sequence - 9

7 Construction Method - 10

7.1 Positioning 7.2 Setup and run the Testing 7.3 Drilling, Sampling and Field Testing 7.4 Testing in Laboratory 7.5 Finishing and Backfilling the Drilling Hole 7.6 Final Report 8 Laboratory for sample testing - 13

9 Survey Result: - 13

Estima t e : - 14

Appendixes

Appendix I - Location of map and Estimated quantity Appendix II - Construction Schedule

Appendix III - Site Organization Chart

Appendix IV - Inspection Sheet for Boring Log

Appendix V - Profile of Laboratory ( to be submit later)

THE METHOD STATEMENT FOR GEOLOGICAL SURVEY

CIVIL WORKS PACKAGE A7, KM 190+420 – KM 218+040

NOI BAI – LAO CAI HIGHWAY PROJECT

1 General view:

1.1 General introduction:

 Civil works: Package A7 belong to Noi Bai – Lao Cai Highway Project

 Location: The package A7 of Noi Bai – Lao Cai highway project (Stage 1) is started

at station Km190+420 in Van Ban district and ended at station Km218+040 in Bao Yen city in Lao Cai province The total length of this package is 27.62 km with 4 vehicle lanes

 The Construction Contractor: Guangxi Road and Bridge Construction Co., LTD

 The Client: Viet Nam Expressway Corporation (VEC)

 The Supervision Consultant: Getinsa Ingenieria S.L (Spain)

1.2 The aim of survey:

To collect the previous geological survey documents and to survey additionally in order to ensure enough geological data according to actual standards, codes for making shop drawings, construction drawings and deploying the construction works

of the Contractor

1.3 Codes and Standards for Survey and Design:

 Standard for Expressway Design TCVN 5729-1997

 Bridge Design Specification 22TCN 272-05

 Standard for Highway Design TCVN 4054-2005

 Standard for Highway Survey 22TCN 263-2000

 Standard for Geological Survey 22TCN 259-2000

 Survey and Design Standard for Falling and Slip Area 22TCN 171-87

 Survey and Design Standard for Soft Soil Embankment 22TCN 262-2000

2 Additional Geological Survey:

2.1 Plan of borehole position and anticipated volume:

Please see at appendix I

2.2 Content of Geological Survey :

2.2.1 Geological Survey for Highway:

 To collect all previous geological surveyed data of package A8 including the

 To carry out the geological bored-hole in the shop drawings stage as below:

 For locations of RetainingWall (the notation for geological bored holes in this stage is SDRW):

 The work of geological survey shall be carried out basing on the topography plan, longitudinal profile and cross sections that have been done in this shop drawing stage

 Investigation boring: carrying out survey drilling at culverts that not drilling at previous design steps

 The number and locations of bored-holes shall be seen in the attached Appendix Drilling into bearing capacity soil layer is continuous about 10m(cohesionless soil with SPT>10, cohesion soil >8).The proposed depth of investigation boring is 10m

 Requirements for Drilling and Collecting Samples:

 Standard Penetration Test: 2m/1 point

 Collecting samples for stratum definition is 2m/sample, the number of testing sample is about 60%

 Locations and the proposed depth of borehole shown on appendix 1

2.2.2 Testing in Laboratory:

 For Samples collected from bored-holes:

 For undisturbed cohesive soil: particle size analysis, moisture content, specific gravity, liquid limit, plastic limit, cohesion (at saturation state and natural moisture state), internal friction angle (at saturation state and natural moisture state), compressibility coefficient, coefficient of permeability

 For fill embankment on soft soil, the soft soil characteristic shall be tested: consolidation coefficient, pre-consolidation pressure, compressibility index, re-compressibility index, undrained shear strength, consolidation drained shear strength, consolidation undrained shear strength

 For disturbed cohesive soil: particle size analysis, moisture content, specific gravity, liquid limit, plastic limit

 For sandy soil: particle size analysis, specific gravity, dry rested angle, saturated rested angle, maximum void ratio, minimum void ratio

 For rock: name of rock, unit weight, compression resistance strength (dry and saturation state), softened coefficient, rock quality designation (RQD), weathered rate, point compression strength

2.2.3 Other Requirements:

 It is required to take photos at each bored-hole locations

 Taking photos and making additional reports for expressway areas that have special dynamic geology phenomenon such as: flood stream of soil and rock, scouring ditch, karst, landslide, falling etc

 Notes for geological surveyed report:

 It is required to make the geological longitudinal profiles for all main expressway and access roads

 It is required to make the geological cross sections for all cross sections from topographic survey

 When making the geological report (demonstration, bored-hole location plan, geological longitudinal profiles and cross sections, characteristics summary of physics and mechanics), the geological surveyed unit at this shop drawing stage is responsible for combining the results of surveyed data (bored holes, physics and mechanics characteristics) from the shop drawings stage and the previous stages (the feasibility study stage, the detailed design stage) into the geological report for the shop drawing stage

 During the surveyed time if any soft soil and landslide areas are found, the surveyed team is responsible to inform immediately to the Supervision Consultant, the Client and the Contractor VINACONEX

in order to consider carrying out additional survey at these areas

3 Construction Schedule:

Please see in the Appendix II

4.Site organization chart

Please see in the Appendix III

5 Equipment and Machinery

The quality of all equipment should be checked carefully before mobilizing and/or commencing the work in order to avoid any unexpected risks

Table1 - List of Equipment, Tools and Machinery for Construction

Note:

Above stated quantity of equipments could be changed if any required and necessary

6 Construction Sequence

16 Floating system

Preparation Equipment Check Mobilization

Positioning

Setup Run the Testing

Drilling and Sampling Field testing

Finishing Backfilling of Borehole

Preparing Report

Maintain sample Transfer to laboratory Laboratory testing

Report Submission

7 Construction Method

7 1 Positioning

The positions and elevations of each borehole will be pointed out or checked by proper survey equipment and in demand of consultant The positions should be marked by bamboo stakes

In case of drilling over water, anchorage of floating system will be carried out simultaneously with positioning of borehole The floating system will be anchored

by 4 strands

After positioning, it is necessary to keep stability of floating system

7.2 Set up and Run the Testing

The machine and equipment drilling stands should be setup by the manner so that the axis of rotation coincide the axis of borehole After setting up the following item should be checked carefully:

1) Reliability and precision of machine

2) Lubrication of parts

3) Movement status

4) Status of wire at winch, pulley

5) Damper status

6) Technical status of engine

7) Status of safety part

After checking and correcting all mistakes, run the Testing will be takes place

7 3 Drilling, Sampling and Field Testing

a) Drilling

This work will be conducted by using rotary drilling method and using bentonite liquid for maintaining of borehole wall

b)

Sampling

During drilling samples will be taken at 2m interval or at each change of strata Disturbed samples and undisturbed samples will be carried out by using thin-walled metal tube in conformity with AASHTO T207 for soft soil or Open tube for others After using, all the sample should be maintain in such good manner as specified in Specification of Project so that the its properties will not be changed

See Appendix I for sampling and test location

c)

Standard Penetration Test (SPT)

SPT will be taken at 2m interval or at each change of strata whichever is lesser to obtain shear strength and identify the soil’s properties following ASTM-D1586 This test is done by the number of blows required to take a standard split spoon sample by 30cm, using a mass of 63.6 kg falling from a height of 76.cm 30 cm terminals penetrate on 45 cm sum total penetrate into the soil The static ground water level will be recorded carefully for each borehole

7 4 Testing in Laboratory

The laboratory test will be conduct on about 60% of all samples which be taken at site The physico-mechanical characteristics of each sample will be tested as follows:

a) Undisturbed Sample: Natural water content (W%), Grain size (P%), natural wet density (γww), Specific gravity (Δ), ), Liquid limit (WL), Plastic limit (WP), Compressibility coefficient (a), Shear strength in lateral un-expansion condition (C, φ) )

b) Disturbed Sample: For cohesive soil: P%, Δ), , WL, Wp, W% For cohesionless soil: P%, repose angle αc và αw, Specific gravity (Δ), )

c) Rock sample: density, Compressive strength dry state and saturation state, softened coefficient

The following test will be conducted:

2.Grain size analysis (ASTM D422)

5.Direct shear test (ASTM D3080)

6.Unconfined compression test (UC) (ASTM D2166)

7.Consolidation test, (Cv) (ASTM D2435)

7 5 Finishing and Backfill ing the D rilling H ole

Due to some geological survey locations will be carried out near dykes or existing public roads and highways, the drilling holes should be backfilled after completion to keep or limit changes on properties and status of soil layers and keep safety for living and working of local peoples

a) Backfilling Method

- Use clay or sandy clayer soil for backfilling

- When backfilling, the soil shall be rolled into pieces whose size is about 1/2 or 1/3

of the diameter of hole

- Drop gradually such rolled soil into the holes Do not drop tumultuously to avoid blocking holes

- Use the drilling rod to compact the soil in the hole

- Finally, each hole is marked by wooden stake for inspection later

7 6 Final Report

If so requested by the consultant Engineer, we will supply on the working day following completion of the bore the following information

1) Structure name 2) Bore exact position and code number

3) Reduced level of top of bore 4) Date and time of boring

5) Diameter of bore 6) Depth to which bore of each stratum

7) Type of plant used 8) Depth to base of each stratum

9) Description of stratum structure 10) Depth and results of in-situ tests

11) Static water level 12) Remarks

8 Laboratory

Shall submit later

9 Survey Result:

 The geological survey report in English and Vietnamese: Data sheet in Page A4, Drawings in size A3.Report have 06 copies

 A compact disc contains survey report files

Construction contactor GuangXi Road and Bridge Construction Co.,LTD would like to submit this Programme to the Client (VEC) and the Consultant (Getinsa Ingenieria S.L) for approval

Ha Noi, June, 5Th 2012

Project Manager Of A7 civil works

Appendix I

Location map of boreholes and Estimated quantity

Refer to next pages as attached

(1) Table of Boring Hole Quantity and Location, Sampling and Field Testing (SPT)

(2) Location map of boreholes

Appendix II

Construction Schedule

Refer to next page as attached

Appendix III

Site Organization Chart

Refer to next page as attached

Appendix IV

Inspection Sheet for Boring Log

Refer to next page as attached

Appendix Ⅴ

Profile of Laboratory shall submit later