Nghiên cứu phương pháp thiết kế và thành lập lưới khống chế thi công các công trình giao thông dạng tuyến

Nghiên cứu phương pháp thiết kế và thành lập lưới khống chế thi công các công trình giao thông dạng tuyến

Presentation Organizational method and constructing techniques

Project: Upgrade and improvement of Road 39-2 (Trieu Duong –

Diem Dien segment) Package nip/cp-14a (km64+000.00 -:- Km74+432.00)

Item: Manufacturing precast elements (culverts and

culvert head) and installing culverts Owner: Management board of Project 02 – pmu 02

Designing

consultant: Smec

Contractor: Joint-venture contractor: songhong – Trico – Thanh

Nam

Content

-Part 1 Constructing method and basic technical solutions 1 Foundation to develop constructing method……… 4

2 Introduction to constructing work items ………4

2.1.Introduction to items ……… ………4

2.2 Work volume……… ……… 4

2.3 Progress……… ……… 4

3 Temporary works for construction ……… ……… 4

4 Introduction to machinery and materials for constructing work items …… 5

4.1 Machines for casting culvert head, plate and installing culvert ……… 5

5 Material……….6

5.1 Steel and iron……….6

5.2 Concrete ……….6

5.3 Sand ……… 7

5.4 Ballast ……… 7

5.5.Water… ………7

6 Detailed constructing method for culvert head and plate casting ……… 7

6.1 Constructing site preparation……….7

6.2 Manpower………7

6.3 Reinforcing ……… 7

6.4 Forming ……… 8

6.5 Concreting ……… 8

7 Detailed constructing method for on-site culvert installation 7.1 Prepare constructing site ……… 10

7.2 Ground handling and sand pad layer ……… 10

7.3 Culvert transport and installation ……… 10

7.4 Culvert completion ……….10

Part 2: Organizing the management for assuring the works quality

1 Method of quality assurance ……….11

1.1 Input quality control ……… …… 11

1.2 Selection and use of the most appropriate machineries on the work site ………… 11

1.3 Arrangement of the manpower for execution … ……… .11

1.4 The execution process control……… 12

2.Management of construction materials ……… 12

2.1 General Provisions ……….12

2.2 Additives for concrete ………12

2.3 Organization of acceptance ……… 12

Part3 The labor safety, anti-fire, explosion and environmental sanitation measures

1 Labor safety: ……….13

1.1.Safety condition upon commencement ……… 13

1.2.Safety condition during commencement ……… 13

1.3.Policies for the laborers……….13

1.4.Method of improving the labor condition, comforts for daily life .13

………

2 Safety technique for each construction step:……… 14

2.1.Safety in organizing the works plan ……….14

2.2.Electrical safety on the works site ……… 14

2.3.Safety in using the portable tools ……… 15

2.4.Safety in using the motorbikes, construction machines

.15 ………

2.5.Safety in welding works ………16

2.6.Safety in the formwork, steel reinforcement and concrete works 16

… ………

3 Explosion and fire ………17

3.1 Standard, codes for fire, explosion prevention: ……….17

3.2 Fire prevention measures on works site ……….18

3.3.Organization of the fire prevention system management apparatus 18

… ………

4 Environmental protection: ………18

4.1 Environmental protection: ……… 19

4.2.Method of solid waste preservation ………19

4.3.Protection of technical infrastructure works and green trees ………19

5 Method of safeguards, security, social order: ……….19

Part 4 Conclusion and recommendations

-Part 1 Constructing method and basic technical

solutions

1 Foundation to develop constructing method

- Profile of constructing design

- Decree 16/2005 on Investment and Construction Management

- Decree No 209/2005 on quality management of constructing works

- Technical standards AASHTO and technical regulations of the project

- Work site status and other supply conditions like electricity, water of the area

- Professional capacity of the Contractor and market survey information

2 Introduction to constructing work items

2.1 Introduction to items

Item: Manufacturing precast elements (culverts and culvert head) and installing culverts, Package NIP/CP-14A: Upgrade and improvement of Road 39-2 (Trieu Duong – Diem Dien segment)

The item is composed of main works as follows:

+ Constructing BTCT culvert head with the diameter of 1000 mm

+ Constructing precast support for BTCT culvert head with the diameter of 1000 mm

2.2 Work volume

Constructing volume is based on tender and constructing design drawings of the project

2.3 Progress

Starting time: 05/2009

To ensure progress of drainage system as well as common project progress, the contractor arranges two constructing team to carry out casting parallel structural elements: culvert head casting team and culvert head detaching culvert team Basing on progress, contractor shall adjust culvert head suitable with the practical constructing condition on the site

The elements to be cast is large and multi-type, and depend on progress in working the road, the constructor shall adjust casting progress of elements corresponding to common progress of the package

3 Temporary works for construction

Site hunts and auxiliary works are constructed on the area of 3000 m2 including: site hunts for accommodation, material stock, element casting site, element drying site, water tank for life and construction, drilling well, other facility to serve life on the project site (See the annex)

Table of temporary works

2 Worker house Piece 01

3 Material stocks Piece 01

4 Element casting site m2 1500

5 Element gathering site

6 Other

4 Introduction to machinery and materials for constructing work items 4.1 Machines for casting culvert head, plate and installing culvert

- The contractor shall arrange sufficient machines and equipments to serve the construction and ensure proposed progress

- Machinery is gathered to the request and constructing progress corresponding to features and volume of work items The contractor shall make plan to avoid negative work construction

- Motorbikes serving the construction are always checked, maintained to ensure good operation

Equipments for craft casting work

country

Year of manufacturing

1 Self-moving culvert 1 piece Korea 1995

2 Excavator 0.8m3 1 Piece Japan 1995

3 Forced shaker 1 Sets China 2007

4 Mixer 350L 2 Piece China 2007

5 Compactor: 450KW 5 Piece China 2007

6 Power generator 5 KW 1 Piece Japan 2000

7 Electricity welding machine:

150KW 2 Piece Japan 2007

8 Culvert shaping form

- Culvert head D1000

- Culvert plate D1000 20 Sets20 Sets

Vietnam 2007

9 Metal cutter 02 Piece Japan 2007

10 Concrete casting form 9x2 Sets Vietnam 2005

11 Water pump: 4,5KW 2 Piece Vietnam 2005

12 Subordinate equipments to support reinforce concrete transport to the construction site

13 Measurement like square meter, metric ruler, shrinkage level

14 Method to maintain concrete…

15 Transporting automobile: 8-ton lever, 1.25m3/bowl exacator, 110CV earth mover

5 Material

- All the materials used for the work must ensure all regulations on technical standard described on approved design, quality certificate issued by manufacturer, sample test

certificate as well as state current regulations and approved by supervising consultant and owner before construction

5.1 Steel and iron

-Steel used for the work is of type approved by consultant and owner to ensure quality according to project technical regulation and subject to AASHTO M31 (ASTM A615), -Steel, before use, must be ensure to be non-rust, oil-free and dirt-free

- Contractor shall take test sample for each steel batch according to AASHTO T68 Steels must have quality certificate and label as required and ensure resistance to tension, bending and be approved by consultant

- Contractor must submit to consultant origin certificate of each product batch transported

to the site including:

+ Manufacturing country

+ Standard governing manufacturing

+ Physico-mechanical and experiment table for each manufactured steel batch

For each diameter, each steel grade, batch is required to be 20 tons Each steel batch, as transported to the site, with sufficient certificates shall be taken 9 rods for testing: 3 sample for

tension, 3 for bending, 3 for welding test

- Steel rods must be stored far from the ground, in-house or with suitable cover

- Reinforcing must be machined according to AASHTO standard in right shape and dimensions as specified on the drawings all the reinforcing must be coolly bent, except for other agreement

5.2. Concrete

- The concretes used for the work are those approved by consultant and owner

- The concrete is regularly supplied to the request of work progress with quality certificate for each manufacturing batch 3 month old concrete must, before use, be subject to quality test to ensure fulfillment to ASTMC150 standard (AASHTO M85)

5.3 Sand

- Supply must be clean, dirt-free yellow sand that follows AASHTO M6 requirements Sand quality check must be governed by ASTM standard Sand sample must be submitted to the Owner and Consultant and only used upon agreement by Consultant

5.4.Ballast

- Ballast used for the work is carefully selected with the right dimension and design

(ASHTO M80 Standard) Quality check of ballast for concreting must follow ASTM C33

- Ballast, before use, must be agreed by the Owner and Consultant

5.5 Water

- The contractor shall drill well and pump water to the tank, filter Water for construction must be tested to ensure specification and agreement by the Consultant

6 Detailed constructing method for culvert head and plate casting 6.1 Constructing site preparation

- Arrange constructing site near the site

- Use earth mover combined with manual earth leveling to create constructing site

- Build site huts for workers and technical officers, yards, material and machinery stocks

- Gather materials and equipments on the site

6.2 Manpower

- Workers are arranged into 2 teams of 15 people/each

- Direct constructing workers: 15 worker/team

+Framework worker: 02 workers/team

+ Rigger: 02 workers/team

+ Iron worker: 04 workers/team

+ Wielding worker: 01 worker/team

+Other: 06/team

6.3 Reinforcing

Reinforcing is machined corresponding to ASSHTO Standard and Project Technical regulation

+ Preparation: Ensure that the steel is clean, rust-free, dirt-free and oil-free Before

machining, it is required to check the diameter and type of steel

+ Cutting: Basing on the approved drawings, each steel type shall be cut by cutter to ensure sufficient volume

+ Bending: Steel shall be bent in the right shape and dimensions specified on the design drawing Machined steel must be bound in bundle with code and elements

+ Installation: steel is transported to the constructing site in right volume described on the drawings Along steel stick is grout-cast wedge with the thickness equal to that of

protecting concrete layer as designed

+ Fixing: Steel is fixed, connected and linked together by binding or wielding according to design

+ Testing: The contractor is responsible to show certificates to demonstrate steel quality; and at any time of doubt for steel quality, tested sampling is required

- Acceptance check of reinforcing:

+Before constructing concrete, it is required to make acceptance check minute including: Consultant and technician officer of contractor

+ Before concreting, it is required to inform Consultant 12 hours in advance for carrying out acceptance check of reinforcing and issuing approval for construction

6.4 Forming

Form: Form must be accurately constructed in the right shape described in the drawing to ensure stability and resistance to deformation as concreting

- Before concreting, form must be closely attached without clearance and with smooth surface

- In addition, form must be clean from dirt, sand, and other contaminant affecting

concrete quality

- Form must be oiled (non-fading material) with non-stick lubricant to facilitate

detachment after concreting

- Carry out acceptance check to move to the following step

6.5 Concreting

Concreting is carried out according to ASHTO/ASTM Standard mentioned in Project Technical Regulation

Concrete to be used must be on-site mixed concrete by 350 L mixer Care must be paid to concreting: check the shrinkage of concrete by shrinkage cone Compacting period and time must

be considered to avoid spongy concrete

 Preparation

Before concreting, good preparation must be carried out based on the principles as follows:

- Check and make distribution table posted on the site

- Prepare sufficient manpower, machinery in satisfactory operation, power, wire and safety measures

- Clean form by spraying water, oiling

- Do final check of form, reinforcing

 Concreting:

- It is required to understand the mixing ratio, especially apply strict control of the water volume All materials are at equal ratio; therefore, it is required to carry out accurate balance of materials: tolerance of +1% for concrete, +2% for coarse concrete; +1% for water The order to put material into mixer: concrete input between sand and ballast Then, watering is applied during the mixing Mixing time must be determined basing on capacity and features of mixer as well as mixiability of mixing compound However, the normal mixing period fluctuates in the range of 10 – 15 minutes

 Concreting:

+ Concreting culvert head

- Concrete is continually mixed by two 350 L mixers and transported by bleck truck to concreting site

+ Concreting culvert

- Concrete is continually mixed by two 350 L mixers and poured into bin Then self-moving crane is used to pour concrete in cap of shaker to make concrete spreading to surrounding and fill culvert head walls

 Concrete compacting:

+ Compacting concrete for culvert plate

- Concrete is tightly compacted by compactor In addition to electricity compactors; there are some backup compactors

- The distance to move compactor must be maximum 1.5 times compared with effect radius of the beam

- Choose vibrator to compact with the compacting time on each position of 30 seconds at maximum When concrete layer is 30 cm thick, compactor is run non-load before

inputting concrete

- Position compactor head in vertical dimension after completing one position and then gradually draw compactor up to move to another position

- The signal to indicate complete concrete compacting is that concrete water is collected along the form edge without grout shrinkage

- Excessive compacting in one position is not allowed to avoid concrete layering

- Compacting must be even without any miss that lead to deflection of form and

reinforcing

+ Compacting concrete for culvert head

- Concrete for culvert head must be compacted on a forced shaker Shaker is equipped with control panel so that it is only required to press control button to start the shaker The shaker operates until concrete water gathers along the form edge without any shrinkage At that time, shaker operator shall stop the shaker and finish concrete compacting

 Concrete maintenance:

- Wet concrete is maintained according to project technical regulation Mechanical blow must be avoided during the maintenance

- Frequency development in 7 first days of concrete mainly depends on concrete maintenance; therefore, the contractor should pay much consideration in this issue Specifically, the Contractor shall assign a concrete maintenance team that is always present on the site Members of this team is aware of all norm procedures as well as significance of concrete maintenance This team is equipped with full working tools including water pump, water pipes, tanks, jute sacking, tilts

- Maintenance of new concrete is the best condition for the fast-setting concrete

Concrete quality is high if it is set in environment with sufficient temperature and moisture

- Concrete maintenance is carried out as follows: after concreting is completed from 1

– 1,5 hours, cover wet jute sacking over the concrete It is also possible to cover high-moisture layers such as wet sand, wet concrete packs

- Apply wet maintenance in consecutive 7 days and nights

- Newly-poured concrete must be covered to prevent impacts of rain, sun and kept wet

regularly

 Sampling:

- Concrete sample must be cast before concreting Depending on the concrete volume for

each batch, we determine number of test samples that shall be tested for strength

according to AASHTO T325-04 and for shrinkage to ASTM C143 Standard

 Form detachment

- This process is carried out when concrete reaches acceptable strength The principle of form detachment is to avoid blow to damage concrete

- Detached form must be clean and transported to new constructing position

7 Detailed constructing method for on-site culvert installation 7.1 Prepare constructing site

 Clean the site by 1.25 m3/bowl excavator, 110 CV mover, 12 ton automobile, in combination with manual methods

 Locate the area for digging foundation pits

 Carry out foundation pits by 1.25 m3/bowl excavator, 110 CV mover, 12 ton

automobile, in combination with manual methods

 Check and relocate culvert center

 Foundation pit materials are transported to the waste site by 12 ton truck

7.2 Ground handling and sand pad layer

 Handle the ground as specified by the design drawings (if available)

 Construct the sand layer of 10 cm thick

- Sand layer is constructed manually and tightly compacted as required

7.3 Culvert transport and installtion

 Reinforced concrete culvert plate and head, once ensuring allowed strength, shall be lifted to truck by 10 ton self-adjusting lever and transported to installing position

- Upon transporting, it is required to rest elements tightly to avoid blow, deformation

 Use 10 ton lever in combination with manual method to move culvert plate and segment to the right position

 Construct the connection in the right procedure

 Construct manhole, absorption pit with lengthwise drainage culvert, construct culvert head and yard for cross drainage culvert (if yard available)

 Bricks used for constructing manhole, absorption pit that have gone through test to ensure work quality and stability

- Grout is mixed in right ratio and tested during construction

 Culvert construction

- Use 12 ton truck to transport materials and pour on pile near the foundation pit

- Manually scatter materials along culvert sides to form 15 cm layer, use MIKASA

compactor to compact the material Upon acceptance check by consultant, the next step shall be carried out

7.4 Culvert completion

Part 2:

Organizing the management for assuring the works quality

1 Method of quality assurance

1.1 Input quality control

The Contractor shall select and procure the main material such as steel, iron, concrete, stone in accordance with correct types, good quality and technical guidance by the Supervising Consultant

Each type of material shall be produced with original certificate, technical certificate, physico-mechanical and chemical properties, testing result by the legal organizations and samples to be submitted to the Supervising Consultant for consideration and approval

The Contractor shall organize the store at the work site strictly according to the preservation procedures for each type of material, and secure that it is in the dry, transparent condition and rational order, and use it according to the correct time The Contractor shall also ensure that the material be transported to the work site after procuring to meet the construction progress The Contractor shall organize the transportation by lorry according to the current procedures, have the record for monitoring each type, facilitate the inspection by the Supervisors and Employer at any necessary circumstance and time

1.2 Selection and use of the most appropriate machineries on the work site

The Contractor shall select the equipment and machineries for execution, portable electrical tools and testing equipment, equipment for checking quality to put to use at the work site to meet the technical requirements suitable for execution plan, technical properties and quantities On the other hand, machines and tools shall be suitable and highly feasibible 1.3 Arrangement of the manpower for execution

This is the decisive element, as a consequence, the Contractor shall arrange the technical staff being the specialized engineers, who have ever executed the similar works The Supervisors under the management of the Team Leader in charge shall frequently monitor and supervise the quality, progress, works safety in order to produce the quick responses for arising matters at the works site

The Contractor shall arrange the team leaders and technical staff to instruct the execution, procure, manage the allocation of material The Engineers shall have the professional standard, management ability and more than that, the sense of responsibility and high discipline, secure that task be completed successfully

The Contractor shall arrange the contingent of iron workers, concrete workers, formwork workers, who have experienced many erection works that require the high technical and quality requirements, and who are skillful, well-disciplined, ready to complete all works 1.4 The execution process control

This is the key aspect that decides the efficiency of the works management, so the Contractor shall organize the light, dynamic, highly efficient leading apparatus

The Engineers shall have responsibility to organize the quality control for material, equipment, control the entire erection and building process according to a continuous, strict schedule at all sections and conduct the unexpected inspections for all material procurements manufactured at the site and prepare the acceptance and take over The Contractor shall at the same time combine closely and facilitate immediately for Supervisors and Supervisor for the design author and high level to conduct the check, the quality check at whatever time and wherever (at the warehouse, at the work site or at the material supply points

The quality control works shall comprise many sections and various measures to be applied

simultaneously:

- Selecting the reliable Supplier, type of trade mark materials

- Checking visually or by the simple tools

- Practical check at the works site by the available tools

- Common check at the standard laboratories

- Conclusion and preparation of quality documents

2 Management of construction materials

2.1 General Provisions

All materials to be put to use for execution of the package shall comply with the following management procedures:

- Materials shall have the origin, source, quality certificate, catalogue etc All these materials shall be submitted to the Employer and Supervising Consultant before procuring the goods

- The Contractor shall only sign the material procurement contract after obtaining the written agreement by the Supervising Consultant before buying the goods

- Material after procurement shall be tested for inspection, the testing shall conform to the technical stipulations of the set of design document, bidding document and current stipulations under the supervision of the Supervising Consultant All test results shall be submitted to the Supervising Consultant

2.2 Additives for concrete

Additives used shall be subject to the requirements as to each item and shall be accepted in writing by the Supervising Consultant

Additives shall not leave any influence on the intensity and strength of the concrete Additives shall not in any way contain the composition of Chloride and Chlorine

The use shall conform to the Manufacturers' instructions

2.3 Organization of acceptance

In each stage of execution, the Contractor shall organize the technical acceptance for works based on stage with the acceptance levels as follows:

- The site acceptance: The acceptance team shall, comprising the site leader, technical staffs, proceed with the accomplished works of the teams

- Basic acceptance: The basic acceptance shall only be implemented after correcting the technical errors of the previous acceptance steps

After organizing the acceptance according to the above mentioned levels, the Contractor shall together with the Employer and Supervising Consultant carry out the completed works acceptance

These acceptance documents shall be kept in the completion documents on works and serve

as the basis for making balance for each stage and the entire works

Part 3

The labor safety, anti-fire, explosion and environmental

sanitation measures

1 Labor safety:

The Contractor shall fully understand the point of view that safety is the above all by the main Contractor and shall organize the measures to secure the maximum safety for everybody and works The labor safety works shall comply with safety technical norm in the construction area, TCVN 5308-1991 and technical regulations of the project

1.1 Safety condition upon commencement

1.2 Safety condition during commencement

After receiving the commencement order, the Contractor shall prepare the design document and construction design for labor safety Once when enough documents area made available shall the Contractor meet the conditions to carry out t he commencement of the works

1.3 Policies for the laborers

- All workers at the works site shall be registered for and be paid for health insurance, labor insurance, accident insurance fully

- All workers shall undergo the proper training, sign the safety commitment before starting the construction and participate in the further training before changing the work

- Worker shall be maintained the rest time, sick leave in the event of accident and other benefits according to the labor law

1.4 Method of improving the labor condition, comforts for daily life

Worker at works site shall work on the frequent basis in the polluted, conditions and environment without maintaining the sanitation: muddy foundation pit, works arising a lot of dust such as soil, sand, cement removal, transportation, concrete, lime, mortar mixing, contacting with toxic material such as painting, welding gas and other toxic elements such as weather, hot, cold weather, noise, strong vibration etc…

Therefore, to protect he health, prevent the common and professional diseases for workers, the Contractor shall take action to secure the labor sanitation, accommodation, eating, daily life for the workers as follows:

- Medicine cabinet at the works site: The Contractor shall arrange a small medicine cabinet with all tools and kinds of medicine used for first aid in case of accident at the works site

- Domestic water: The Contractor shall supply enough water for workers, especially in the summer from 2.5 to 4.0 litters per person per day The portable water shall be clean, sterile water The water for personal cleaning shall be the existing water system Everybody shall have the economical consciousness when using water

- Works site WC: The WC facilities that have been built readily shall be used, the Contractor shall be responsible for making sure that workers are awareness of keeping general sanitation

- The accommodation place for workers shall meet the requirements, provide the best conditions for workers to reproduce the labor force and healthy living

- The Contractor shall provide all labor protective, uniforms, glass, gloves, safety shoes for workers and make it compulsory for everybody to be equipped with labor protective

2 Safety technique for each construction step:

2.1 Safety in organizing the works plan

During the process of organizing the construction plan, the following matters shall be taken notice

- Separating fence shall be erected surrounding the works site and guards shall also be arranged to prevent the non-duty individuals from entering the site

- The master drawing for works plan (refer to the drawing) shall show the site of works, stores for assembling material, way of access, temporal site hut, arranged machineries for construction

- On the site plan and other construction areas, the Contractor shall arrange the drainage system to ensure that construction site plan is always in the clean, dry conditions and water does not remain on the road surface or water is prevented from flowing to the works site foundation pit

- The construction area plan shall be in the tidy, order, sanitary conditions The wastes and impediments shall be removed

- The pits on the plan shall be sealed to secure the safety for travelers and put the fences properly

- The dangerous areas caused by things dropping freely from the above shall be put the fence, the signboard, or protective net

2.2 Electrical safety on the works site

 Electrical safety to the conducting- wire system

- The overhead conducting wire across the traffic roads beneath shall secure the minimum height of 4.5 meters There should be the alarms hung on electrical line to remind of the height of the conducting wire according to the regulations on electrical line crossing the road

- For underground cable line, accidents often occur due to the impact by the excavator When preparing the method of statement for road excavation, the Contractor shall need

to plant the landmarks so that the Excavator shall not cause this kind of accident In many cases, the Contractor shall disconnect the electricity in the cable line when executing the road excavation to make sure the absolute safety for workers engaging in excavation as well as to the cable line

- The heavy machines moving on the underground cable line that fails to be buried to the necessary depth or fails to go through the properly protected hoses shall also the causes