Construction Method- UNDP

8/2/2019 Construction Method- UNDP

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The Green One UN House

Project

INDEX

1. INTRODUCTION

The Green One UN House is the working office of the 16 organization members

of the United Nations in Ha Noi.

The project includes renovating a six-floor building and building some

components with the aim of supporting the unity and coordination in all

activities of the organization members of the United Nations, assisting program

operations, sharing information efficiently and harmonizing overall.

With the aim of using primary resources (such as water and solar energy)

more efficiently, this project hopes to become a model structure for sustainable

creative works with standard green in Viet Nam.

2. CHARACTERISTICS OF EXISTING PROJECT.

Location, area: the UNDP existing office was built on the area of over

5.000m2 on Kim Ma street, Ba Dinh district, Ha Noi downtown, to the left of

Hoan Kiem lake, and to the right of Deawoo hotel, including main building

and ancillary items around.

Adjacent buildings: the northern side is adjacent to Uniworld Internation

School building and Aluminum factory, the eastern is FPT Telecom, RMIT

University and Habubank buildings. The western is a parking lot and the

faade on Kim Ma street is toward to the south.

Transportation: the main entrance is located on Kim Ma Street, a 7-meter-

wide eastern road, is convenient for material, equipment transportation.

Two auxiliary gates in the east, leading to neighboring buildings, are often

closed.

The existing main building:

United Nations Apartment Building (UNAB) in center area of the project isthe working place and accommodation of United Nations officials in the area

of 45.6m x30m. The 6-floor building was constructed with structrural frame

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system: reinforced concrete beam & column base on footing foundation

system, a shear wall in the lift position and finished by brick walls, door

frames, curtain walls around suspended ceilings and tiled floor. The structureis now fully operated with machinery, electricity and water plumb system.

Existing septic tank was arranged outside the UNAB, near the eastern fence.

Additionally, there is it one-story building closely to KimMa Street which

contains a reinforced concrete frame system on the foundation system, a

swimming pool with an area of nearly 160m2, a surrounding brick fence,

adjacent to a tennis court with a steel fence surrounding a playground for

children.

The northwest corner of the building is a pumping station which includes a

reinforced concrete structural frame base on footing foundation, next to a

semi-underground reinforced concrete water tank and power station with

steel roof frame above on reinforcement concrete foundation.

The existing fence surrounding the eastern area near Habubank Bank is open

steel fence while the rest barriers are masonry walls. Landscape plants,

flowers and yards are located along the fence and the internal road leading

into UNAB.

3. SCOPE OF WORKS

In accordance with the invitation to bid and design drawings, the Contractor is to

clarify the scope of works as followings.

3.1 DEMOLITION WORKS

3.1.1 United Nations Apartment Building (UNAB)

Structure:

Demolition of eaves around the building from 1st-6th floor shown in design

drawings.

Demolition of walls, stairs at axis (5-6) & (H-G) from 1st- 6th floor, axis (5-6)

& (C-D) from 5th -6th floor.

Demolition of two water tanks on the 6th floor from axis (C-B), (G-F) and

axis (5-6), all of roof structures such as beams, slabs, columns, water tanks at

axis (E-F) & (5-6)

Achitecture



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Removal of planter boxes and all associated plants & soil at ground floor and

bicycle shed demolition.

Demolition all of interior elements such as brick walls, gypsum wallboards,

ceilings, floor tiles.Dismantlement of doors, windows, glass from the 1st-

6th floors shown in respect of design drawings.

3.1.2 Ancillary items:

Demolition of existing ancillary buildings including: building near the fence

at Kim Ma street, tennis court, playground for children, semi-underground

water tank, pump station and septic tank.

3.1.3 Mechanical & Electrical, Plumping

Dismantlement of all electrical equipment including power station,

distribution board, communication system, CCTV system, air conditioning

and ventilation system.

Removal of all sanitation equipment, plumping, pumping machines.

Demolition of waste management system including septictank, drainage

system.

3.1.4 Landscape

Demolition of curbs, planter boxes and removal of trees around building.

Brick from UNAB demolition will be reused for terraced landscape.

3.2 CONSTRUCTION WORKS

3.2.1 UNAB building:

Structrure

Driving additional piles 400x400mm, concreting additional pile cap for

foundation, concretting shear wall for new lift system.

Increasing the column sections from (400x200) mm to (500570)x

(320360)mm in some locations, reinforcing them with steel anchor system,

angle steel and placing concrete. Concrete space, (5090) mm, is too narrow

for placing concrete. So the Contractor is to propose to use Sika product for

concreting.

Erecting steel beam system connecting to existing reinforcement beams,

columns by anchor bolts with adhesive.



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Placing concrete bond deck slab with decking panel, 150200mm thickness.

Erecting steel column and beam on 6th floor and grating panel on roof.

Erecting emergency steel stair at 4 conners of building.

Achitecture:

Expanding area from axis (F-C) & axis (1-10) with open architecture style

from the 1st to 5th floor. On the 3rd and 4th floors there are to be corridors

connecting two blocks of building.

The external and internal walls shown in architectural drawings are to bemade of brick, gypsum board with insulation, acoustic panel and finished by

mortar, tiles and painted coating. At some locations, there is to be a glass

wall with aluminum sunshades panel.

Ceiling system is to include ceiling finished by mortar and paint coating,

acoustic insulation gypsum board ceiling specified in drawing. Floors is to

be finished by carpets or tiles.

An anluminun sunshades panel system is to be located on the 5th roof,

supported by steel beams connecting to reinforcement (RC) columns &

beams. The top roof is to contain a grating panel system of which

photovoltaic panels and satellite dishes are to be located.

All furniture including desks, chairs, sinage and equipment, plumps are to be

specified in design drawings, supplied and installed by the Contractor.

3.2.2 Entry Buildings

Entry buildings are to include Western Entry Building and Eastern Entry

Building.

Structure

Foundation of western building is to contain strip footing system, of eastern

building is to contain single footing and strip footing systems connected by

foundation beams, based on compacted sand layer. Level of foundation is (-

1.50-1.55)m (ground level)

Structure of two buildings is to include RC columns, walls, beams and slabs.The location of walls, columns are to be specified in design drawings,

section of column is to be 220x400 mm, (200300) mm thickness.



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Thickness of ground slab is to be 200mm. Level of ground slab of western

building is to be +7.100m (TOC), of eastern building: +7.150m, +7.200m

(TOC). Thickness of roof slab is to be200mm; level: +9.750m, +10.550m(TOC).

Architecture

There are to be two entrances leading to the security check area and car park

and a RC wall at Kim Ma street between two entrances.

The buildings are to be separated into function rooms divided by brick walls

shown in the drawings. Ceilings are to be finished by mortar or gypsum

board.

All entire roof is to be covered by green landscape with sky light windows.

3.2.3 Underground Water Tank, Technical Building:

Structure

The foundation of technical room is to be a footing system, on the base of 24

piles, size 400x400mm, connected by ground beams.

The structure of underground water tank is to contain RC walls and RC

slabs. The technical building is to be constructed above the underground

water tank top slab. Thickness of bottom slab, wall is to be 300mm, ground

slab of technical building is to be 200mm, roof slab is to be 200mm with

equipment base 150mm thickness.

Achitecture

Pump machine and equipments are to be laid on roof of the technical

building, circled by acoustic louvre panel.

The building is to be separated by brick wall, including pump room, genset

room, LVSG room and garbage room. Cable trend sytem is to be arranged

under the ground floor and above the water tank. Size of manhole at pump

room is to be 1000x1000mm.

Door system is to include 2-leaf-steel doors, roller doors at garbage room

and louvre windows.

3.2.4 Septic Tank



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Septic tank is to be located underground tank; the structure of septic tank is

R.C slab and wall separated into chambers, based on compacted sand layer.

Thickness of bottom slab, above slab and external wall is to be 300mm, and

internal wall is to be 200mm.

Height of tank is to be 3m, dimension is to be 9.2x2.6m, including 4

chambers divided by processing stage. There is to be a manhole

500x500mm, 800x800mm at each chamber. Walls are to be beveled 45 0 at

bottom slab for convenience of the waste deposition.

3.2.5 The walk way

Structure of walk way foundation is to be a footing system based on

compacted sand layer, placed along walk way.

Structure of frame is to include R.C circle column diameter 400mm, steel

circle column size 100mm connected by 4 embedded bolts in foundation

for R.C roof structural frame support.

The walk way is to connect the eastern entry building to UNAB building.

Roof of walk way is R.C slab with shape shown in degisn drawings.

3.2.6 Landscaping

Landscape is to include terrace garden at the west and east sides of the entry

buildings and plant along the main building with lighting system (refer to

drawing for specification).

From entrance, car park is to be located between two entry buildings, water

feature is in front of UNAB. Drainage system is to be located in the area

between UNAB and Entry Buildings.

3.2.7 Mechanical and Electrical system

Electrical system

Transformer/ Generator system.

Distribution board system.

Lighting, socket outlet system.

Lightning protection and Earthing system



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Communication system.

BMS system.

Fire Protection system.

Plumping and Drainage system.

Fire Protection system.

Air conditioning and Ventilation system.

3.2.8 Testing, Commisioning and Handing Over General:

The Contractor shall arrange all submissions to Authorities and pay the cost

of statutory inspections and certificates.

The Contractor shall be responsible for obtaining all necessary licences as

required by all relevant authorities before operation of any

equipment/system.

All testing and commissioning to enable proper operation of the Works shall

be completed to the satisfaction of the Contractor and Project Manager

Factory tests:

Type test of equipment shall be tested at the manufacturer's works or

elsewhere as Center of Quality Test Registration and `Type-Test' certificate

shall be provided by the manufacturer's.

On - site testing and commissioning:

All instruments, tools, material and labour required to perform these tests

shall be provided by the Contractor.

Before the testing and commissioning are carried out, the Contractor shall

remove all equipment and components which are unnecessary.

The Contractor shall start up, operate, test and adjust the systems in

accordance with shopdrawing approved, schematic diagram or the agreedprogramme.



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Statutory authorities' tests and inspections (If any):

Where acceptance tests are required by the relevant authorities havingjurisdiction, these tests shall be carried out by the Contractor prior to the

issue of Completion Certificate to the acceptance of the Authorities

Preliminary commissioning checks:

The Contractor shall carry out cleaning, lubricating (if any) and checking

thoroughly for all equipment before installation and commissioning.

Final adjustments or final acceptance test and commissioning:

The Contractor shall perform all tests and adjustments to the plant and

equipment to attain the specified performance and conditions of operation

before commissioning.

Following commissioning activities of the entire installation, and prior to

issue of the Completion Certificate, the Contractor shall carry out final

acceptance tests in accordance with a programme approved by the Owners.

Warranty and handover:

After Testing and Commissioning, and when the Project Managers is

satisfies and agrees that the installation is ready for handing over to the

Employer, the plant shall be finally commissioned and Installation Manuals

together with As-built drawings shall be provided as specified.

If the test results show that the plant and equipment is functioning in a

satisfactory manner or complying with the performance requirements of the

Specification, handing over shall be considered and executed.

4. PROJECT PROGRAM

4.1 CONSTRUCTION SEQUENCE

4.1.1 Demolition

4.1.1.1Principles for demolition

After studying and understanding the scope of work, location and characteristics

of the demolition items the Contractor shall perform demolition works according

to following principles:



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Dismantlement direction of general construction layout is to be from the

inside out, from north to south towards the main entrance on Kim Ma street.

Demolition from the topdown.

Ensuring practicable acess for garbage and debris transportation.

4.1.1.2Demolition Procedures

Dismantlement time for UNAB item is to be estimated larger than that of the

remaining item dismantlement. Thus, two groups shall be arranged, one team

(team 1) to carry out UNAB demolition works, the other (team 2) for the

remaining items. Based on the principles of demolition, the Contractor shallconduct demolition works as the following order:

The priority work is to build temporary office for the Owners and the Contractor

at the playground, adjacent to the northern corner of the tennis court. The

playground demolition works is to include: landscape, brick fence around the

swimming pool, tennis courts.

During the construction of the temporary offices, the Contractor shall carry out

preparatory work for UNAB demolition. After completion of the temporaryoffice, team 1 shall execute UNAB demolition. The order of demolition UNAB

is to be shown in detail in the later section.

Team 2 shall first proceed to demolish the pump station, semi-underground

water tank, transformers first, and then swimming pool, auxiliary building and

septic tank.

Northwest semi-underground water tank has narrow construction layout which

creates hinder for transportation. The western acess, 3 meter width from the

existing fence to the edge of the scaffolding cover is not practicable for

construction transport. The eastern acess 5m width is to be utilized for

machinery and soil transport. Therefore, septic tank is to demolished after the

completion of excavation work for underground water tank.

Existing fence, landscape and plant is to be retained during UNAB demolition,

and only be dismantled, relocated for a new building construction at the later

phase of the project.

4.1.2 New Construction Works

4.1.2.1 Principles for new construction works



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After studying and understanding the scope of work, location and characteristics

of the construction items in the new design, the Contractor shall conduct

construction works in accordance with following principles:

Construction direction on the general layout is to be from the inside out,

from the north to the south towards the main entrance on Kim Ma street.

Construction is to be carried out from the bottom up.

Practicable access for machinery, construction equipment transportation

must be ensured.

4.1.2.2Construction Procedures

Construction time of new UNAB is to be estimated larger than that of remaining

items. Thus, during the construction process of UNAB, the Contractor shall

balance the construction schedule of the remaining items to ensure efficient use

of resource and arrange neat execution layout. Based on the principles of new

construction works, the Contractor shall conduct the works as the following

order:

UNAB

Immediately after completion of UNAB ground floor demolition, the

Contractor shall carry out jacking working piles for additional foundation

construction.

Flooring and reinforced column construction is to be conducted in sequence

from the bottom up. Total time for superstructure, expected to be completed

on 08/05/2013, is to be 272 days including steel roof. Finishing works and

MEP equipment installation is to be carried out simultaneously with the

execution of the frame structure, scheduled for completion by 31/07/2013.

The Auxiliary Items

Immediately after completion of the demolition and semi underground water

tank backfilling, the Contractor urgently perform pile driving, underground

water tank and new technical building construction as per new degisn.

Septic tank must be piled and excavated after completing underground water

tank excavation to ensure convenient transportation for debris transportation.



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After the technical building is to be completed, the Contractor shall carry out

Western Entry Building behind temporary site office.

In order to continue the construction of East Entry Building and Walk Way,

the Contractor shall open a temporary access between entry buildings, a 4.6-

meter- wide acess coinciding with the main entrance of the new building as

per latest design to ensure clear transport for machinery and equipment.

Fence, Terraced Landscape

Fence: Fence item is to be divided into four sections.

Section 1 is to include northern area of the project, connected from thetechnical building to the septic tank. This section is to be executed as soon as

the technical building completion.

Section 2 is to be located in the western area of the project, connected from

the technical building to western entry building. This section is to be

executed as soon as section 1 completion.

Section 3 is to be located in the eastern area of the project, connected from

the septic tank to entry buildings. This section is to be executed as soon asthe section 2 completion.

Section 4 is to be located in the eastern area of the project, around main

entrance on Kim Ma street. This section is to be executed as soon as the

section 2 complettion.

Underground Item: cable trench, drainage system is to be conducted

simultaneously with the fence execution. Excavation work is to be divided into

areas and step by step construction sequences, to ensure no traffic jams and neat

construction site

In order to release ground layout for underground item execution and terraced

landscape, temporary site office is to be dismantled and removed to UNAB

ground floor.

Terraced Landscape: landscaping items is to be divided into four areas:

Area 1 is to be located round UNAB and pritority executed after

underground construction completion.



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Area 2 is to be located on the western walk way, behind western entry

building and conducted after the completion of the western fence section 2

and a landscape area 1. Bricks of UNAB demolition are to be reused forterrace wall construction.

Area 3 is to be located on the eastern side of walkway, behind the eastern

entry building and executed after the completion of the eastern fence section

3, walk way item and landscape area 2. Bricks of UNAB demolition are to

be reused for terrace wall construction.

Area 4 is to be located in the eastern area of the project including entry

building finishing works. Car park is to be conducted after completion of thesouthern fence section 4 and entry building roof.

Plants after being removed to caring garden are to be brought back and

planted in the required place.

Testing- Commisioning

After completion of the construction and installation of equipment and

connection of MEP systems, the buildings security system, Testing-

Commissioning activites is to be carraid out before handing over to the Owners.

Testing- Commissioning works is to be applied to ensure project technical

requirements:

Testing and Commissioning for Electrical & ELV systems.

Testing and Commissioning for Sanitary & plumbing systems.

Testing and Commssioning for Fire Protection systems.

Testing and Commissioning for HVAC systems.

During testing- commissioning, the Contractor shall invite the Owners to

inspect, and then last repair defect works before handing over the project.

4.2 PROJECT SCHEDULE

(See Appendix 1)



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5.LOGISTICS PLAN.Based on the nature of construction work, the site is to be located in a limited

and crowed area, including adjacent buildings. Therefore, the Contractor has

considered construction layout thoroughly to arrange the transportation, office

location, store and yard in the most logical way.

5.1 TRANSPORTATION

Entrances, internal roads: Vehicles are needed for transporting materials,

equipment, garbage, and construction machines. So the entrance and internal

road are to be arranged reasonablely for no obstruction in transportation. The

main entrance from Kim Ma street straight to the building UNAB is to be be

very convenient for traffic and create no affect on the execution layout

during demolition. So the Contractor is to keep the main entrance and

existing internal roads to serve the construction.

When western entry building is to be constructed, main entrance and internal

roads are to be relocated to the new place which is between two entry

buildings, running straight from Kim Ma street and of which no obstructionsare to impact on construction layout.

Wheel washing system: the vehicles during the construction of the wheel

stick in a lot of dirt, garbage. Due to high environmental requirements wheel

washing system including workers with pump machines are to be arranged at

entrance for vahicles to be washed before transporting out of site. Waste

deposition system and waste water is to be treated before being put into

common drainage system.

Fences: fences play an important role of security, control work, in addition

to minimizing the effects of constructrion such as dust and noise to adjacent

areas. Therefore, the Contractor shall maintain the existing brick and steel

fences and reinforce them with adhered steel plate to the height of 2.5m for

safe construction.

Site hoarding: due to an international project, the site faade on Kim Ma

Street is to be mounted with advertising project panel made of background

color canvas. Existing front fence is to be made of brick, so the Contractor

shall build up a new front fence for the panel of which content and form will

have been approved by the Owners.



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5.2 SITE FACILITIES

Temporary Office: prior to demolition of the main items, the Contractor

shall arrange temporary office for the Owners and Contractor. In accordance

with specification volume 1, item 1.3.2.3, the Contractor shall build

temporary office of 210m2 with full range of required design features. Based

on construction layout, the Contractor has found out that the vacant space at

the playground adjacent to tennis court not only creates no affect on traffic

but also locates western guest house which is be constructed later,

convenient for construction works accordingly. Therefore, temporary offices

is be arranged in this vacant space (refer to drawings for specific position).

Temporary office is be relocated to gound floor of UNAB building when

landscaping behind western entry building is to be constructed.

Temporary toilets: due to narrow space, the Contractor shall utilize the

mobile toilet for convenience of construction layout.

5.3 WATER AND ELECTRICITY

Electricity: the Contractor shall use the power available for construction.

The position of the current generator is to be on intentional construction

roads, so the Contractor shall move it and arrange other backup generator

320KVA at the new location for construction convenience.

Each distribution board is to be installed 01 circuit-beaker against leakage to

ensure safety construction. For main equipment individual distribution board

is be installed to control and protect equipment, such as: tower crane, hoist,

welding machine, pump machines

Lighting: 400W high pressure lamps are to be arranged logically to assure

sufficient light for construction, security and order within and outside the

building.

Water construction and activities: the Contractor shall use existing water

supplies leading to 5m3 water tank and pump to the roof tank to serve the

construction. The Contractor is to retain a roof tank and demolish it later.

At the auxiliary structures surrounding construction area, manhole andtrench are to be connected to drainage system or to be pumped to the city

sewer system.



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Installation of plumbing and waste sorting process before being released to

the drainage system

5.4 MAJOR EQUIPMENT (FOR UNAB):

Hoist: during dismantling work, all equipment is to be removed from the

topdown, so the Contractor shall conduct a two-cage hoist to reduce the time

and manpower. This hoist is to be utilized to move demolition devices:

sanitary, electric equipment

After studying design drawing the hoist is to be installed in axis A & (7-

8) due to not being obstructed by construction area. Additionally, the hoist is

to be in front of empty road leading from internal access to the main gate for

removal and transportation of equipment and materials convenience.

Tower Crane: Chracteristic of refurbish structure is to be steel beam and

column system, erected at site of which Sb-25 beam size is 800x400x20mm,

11.12 length, at axis 7 & (C-F) has the largest volume more than 2T, at level

+19.990m. On the other hand, the construction area after erection of

scaffolding system is to be very narrow; the minimum distance between the

construction fences and scaffolding systems is 2m. So the Contractor is to

use tower crane for erection.

Tower crane is to be located at axis A & (3-4) for several reasons. Firstly,

this location is not to be hindered by later construction. Moreover, the front

area is a vacant space which is to be convenient for dismantlement and

transportation. Finally, the location of tower crane in the middle construction

layout is to be able to serve all construction items of project.

Tower crane 10T Liftec LT6518A/B Specification



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5.5 STORAGE, YARD:

Demolition waste yard/ Rubish chute: reusable equipment is to be

transported by hoist while and all debris, construction waste are to be

watered and then transported by plastic rubbish chute to avoid and reduce

dust pollution.

The area of the axis (1-4) & (ED is a vacant space with internal access which

is to be convenient and spacious for traffic. So the Contractor shall arrange it

as garbage area with waste pipe at axis 5-F anchored to the

scaffold, guiding all debris down to garbage yard. Then, garbage is to be

transported by covered vehicles and dumped at the stipulated place approved

by local authorities.

Equipment yard: For the transport mobility and decreasing loading time,

the Contractor shall utilize three 20ft containers to store the re-use equipment

and relocate in accordance with the Owners requirements.

The Contractor shall arrange containers at the vacant space next to acess road

for transport convenience.



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Material yard: the Contractor shall arrange material yard for later

execution. Gathering area is to be a vacant space, not to affect the

construction layout of other items.

Equipment store: a container is to be used to store the construction

equipment such as cutting machine, concrete breaker, hand tools and

located next to office for the monitoring and inspection convenience.

Reinforcement and formwork fabrication yard is to be arranged at vacant

spaces to avoid negative effects on practicable access in every construction

stage.

5.6 ADJACENT BUILDING PROTECTION

For adjacent building around site, before the start of execution, the Contractor

shall carry out installation of fence surrounding the site.

For execution of building demolition, the Contractor shall carry out scaffolding

cover installation with dustproof mesh and water regularly to reduce

environmental pollution.For minimum noise while execution, the Contrator shall

limit demolition works at night .

For excecution of underground items such as underground water tank, septic

tank the Contractor shall carry out demolition existing fence and driving

larsen sheet around construction area and outside the site. Therefore, the

Contractor shall contact the land owner for permission before construction.

6. APPENDIX

6.1 PROJECT SCHEDULE



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With long experience in construction activites, the Contractor shall coordinate

with the Owners to contact the related authorities for construction layout licence

and to register with local authorities on the construction activities to assuresecurity and order situation of the local region. Other activites such as:

Permit to utilize roads, infrastructure, drainage system

Permit to connect the water supply system.

Power system for construction works.

Sign contracts with specialized industry units on hazardous waste treatment

under the law.

The similar contracts for several project such as:

Documents

Construction Method- UNDP