Methods and Equipment for construction- Project II: Concrete Wall System

The American University in Cairo CENG 423- Methods and Equipment for Construction I

Spring 2012

Project II:

Concrete Wall System

Presented to: Dr. Khaled Nassar

Prepared by: Layla Sabry

Mona Serag

Lobna Houta

Amira Badran

Amr Abd el Aal

Concrete Wall System 2012 Table of Contents 1) 2) 3) 4) 5)

6)

7) 8) 9)

About the Project and Site Background…………………………………………..5 Sequence of work planned……………………………………………………………..7 Safety Assessment of site……………………………………………………………..11 Site Plan……………………………………………………………………………………….11 System …………………………………………………………………………………………11 a. Background……………………………………………………………………11 b. Construction method…………………………………………………….13  Installation………………………………………………13  Finishing………………………………………………….15  Equipment……………………………………………...18 c. Evaluation of System……………………………………………………..24 Alternative methods…………………………………………………………………….26 a. Traditional System………………………………………………………..26  Skeleton Structure………………………………..26  Wall………………………………………………………28 b. Precast Concrete…………………………………………………………..29 Production Rates…………………………………………………………………….....33 Quality Control…………………………………………………………………………….36 Safety Requirements……………………………………………………………………41

10) Reference…………………………………………………………………………………..48 11) Appendix A…………………………………………………………………………………49 12) Appendix B *Biweekly report, site plan and other sample forms available in hard copy only

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Concrete Wall System 2012 Table of Figures

Table 1- Villa Milestone 1 sequence Figure 1 Gantt chart Figure 2: Various Construction systems throughout the world Figure 2-2: An aluminum made-to-order construction frame Figure 3: The use of aluminum formwork for concreting Figure 2: Arches produced by aluminum formwork in Cairo Festival City Figure 3: Installation of formwork by pins and a hammer Figure 4: Single shuttering under roof and double shuttering for beams and columns.

Figure 5: Polystyrene board installed for insulation Figure 6: Boom pump being used for concreting of floor Figure 7: Before and after the removal of aluminum plates Figure 8: Metal hangers used to support scaffolding Figure 9: Walls, stairs and details of walls smooth finish Figure 10: Smooth surface finish of concrete wall building Figure 11: Smooth outer surface of studied project Figure 12: Floor slab smooth surface finish Figure 13: White Undercoating used on site Figure 14: Granite tile with Steel Pins for Mechanical Fixation used on site Figure 15: Mechanical Excavator Figure 16: Small Compactor Figure 17: Roller Single – Roller Compactor Figure 18: Mobile crane Figure 19: Aluminum Formwork Figure 20: Aluminum formwork detail of formwork used on site Figure 21: Pin and Wedge system found in formwork on site Figure 22: Pin and Wedge Connection System Figure 23: Wall ties to hold wall formworks together Figure 24:Props supporting floor slab formwork

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Concrete Wall System 2012 Figure 25: Overview of the formwork system Figure 26: Steel Formwork used on Site Figure 27: Window detail of "Cairo Festival City" Figure 28: Thin window column constructed with the aluminum formwork Figure 29: Concrete Pump Figure 30- hollow block slab Figure 31- Worker assembling the steel reinforcement bars Figure 34- Concrete poured in directly on the steel reinforcement Figure 35- Workers spreading the concrete to create a smooth surface Figure 36- Construction of walls using bricks and cement Figure 32- Precast Wall Panel Figure 38- Welding of Precast Figure 39- Installation of a precast wall welding system New Zealand (A. Charleson) Figure 40- Precast concrete wall system Figure 41- In situ Concrete wall system with openings (wood formworks) Figure 42- Installation of Aluminum Formwork used in Cairo Festival City (Local Case study) before pouring concrete fences.

Figure 43- An example of a precast panel lifted to final placement with a crane Figure 44- an example of in situ concrete pouring through a tube from a pump truck in a project in Serbia Figure 45- The Precast House in Howth Village by FKL Architects Figure 46 - Concrete Wall System in Cairo Festival City, Figure 47: The slump test ASTM C-143 Figure 48: Concrete Cube Strength testing igure 49: An air meter ASTM Figure 50: Typical Formwork setup for a concrete wall Figure 51: Engineer inspecting the joint connection in the erected formwork Figure 52: Formwork at Cairo Festival City

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Concrete Wall System 2012

Project: Cairo Festival City Owner: Al-Futtaim Residential Resorts Development SAE Owner Address: The Ring Road. Taha Hussein St. South Mubarak Police Academy, 5 th District. New Cairo, Egypt.

Project Manager: Al-Futtaim Residential Resorts Development SAE Construction Management Consultant: MIVAN Architect Engineer: EHAF Consulting Engineers Structural Engineer: EHAF Consulting Engineers Mechanical Engineer: EHAF Consulting Engineers Electrical Engineer: EHAF Consulting Engineers Contractor: Industrial Construction & Engineering Co. (SIAC) Job Site Location: Cairo Festival City. The Ring Road. Taha Hussein St. South Mubarak Police Academy, 5th District. New Cairo, Egypt.

General Design Scope: Cairo Festival City offers a number of service communities including Retail, shopping and entertainment, Offices and Living.

Residential Community is planned to accommodate around 13,000 residents, divided on Luxurious Villas and Residential Apartments.

Oriana Villas are situated at the far east of the Layout, 480 Mediterranean Styled villas are to be built on an area of m², covering 20% of the total area, where the other 80% is dedicated to parks and greenery.

Some examples of the variety of prototypes being built are shown below;

Spanish Villa- T3

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Italian Villa- T2

French Villa- T1

Concrete Wall System 2012

Secretary Safety Officer

5 Watcher Accountant Stores

Administration

Time Keeper Personal Office Purchaser Labours Camp sup.

Area Manager

Area Manager

PM(Project Manager) Construction Manager

Area Manager

Area Manager 2 Surveyor Eng.

3 Site Eng. 5 FORMAN 3 Site Eng. 5 FORMAN 3 Site Eng. 5 FORMAN 3 Site Eng. 5 FORMAN 4 Surveyors

Workshops Lab Tech.

Client Invoices Shop D.

T.O.M QA/QC Planning / Cost C.

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Quantities S. Steel Workshop

Subcontrac tor

3 Barlist Eng.

2 Formans

Concrete Wall System 2012 The initial Total estimated cost for 170 Villas built using the Concrete Wall Construction system is 350,000,000 EGP, however, due to a few obstacles, the Concrete system was used to build only 19 Villas out 170 where the expenses ranged between 35 to 36 Million EGP. The expected project submission at a finishing level was initially estimated to be 8 months, using this specific construction system, however, the actual gross time covered for 19 villas was around 1 year and 6 months.

2) Sequence of the Work: Time Schedule The residential villas constructed within the large scale project of “Cairo Festival City� was divided into

7 Milestones, where the first Milestone started on the 28 th June 2009 and was

scheduled to be completed on the 21st January 2010 while the 7th Milestone was supposed to be delivered on the 15th January 2011. However, due to several reason, which are discussed further in the following detailed report this time schedule was not fulfilled. Furthermore, during our visits to the site it became evident that the construction work proceeds in at very slow rate. Since the villas are all constructed using the same construction technique and equipment and the construction period and details fall within the same range, we found it sufficient to document the time line and progress of the work for 2 villas trying to choose two that went through different time schedules.

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Concrete Wall System 2012 Time Schedule from Biweekly Reports and Gant chart Cairo Festival City- Villa Milestone 1

Tasks Villa 1 Excavation Works Preparation Works Scaffold Erection Windows and Doors Frame 1st Fixation Window and Doors 2nd Fix Scaffold Dismantle Concrete Remedials Granite Cladding GRC External Render Slope Concrete amd Insulation Roof Tiles Clay Tiles Villa 5 Excavation Works Soil Replacement P.C. & R.C. Foundations Preparation Works Scaffold Erection Windows and Doors Frame 1st Fixation Window and Doors 2nd Fix Concrete Remedials External Render Granite Cladding GRC Slope Concrete amd Insulation Roof Tiles Clay Tiles

Start Date

Original Duration

% Completed

7/18/2009 12/21/2011 12/25/2011 1/26/2012 4/21/2012 4/23/2012 1/18/2012 3/14/2012 4/7/2012 4/7/2012 3/21/2012 3/24/2012 3/31/2012

5 3 12 4 6 3 25 18 16 16 10 12 12

100% 100% 100% 100% 0% 0% 100% 95% 70% 305% 40% 90% 0%

7/21/2009 12/24/2009 1/8/2012 1/30/2012 4/28/2012 4/26/2012 2/16/2012 4/3/2012 3/24/2012 4/24/2012 3/22/2012 4/8/2012 4/15/2012

7/21/2009 8/2/2009 9/29/2009 2/9/2012 2/23/2012 3/8/2012 4/21/2012 3/1/2012 4/7/2012 3/14/2012 4/7/2012 3/12/2012 3/24/2012 3/31/2012

5 21 12 12 12 4 6 25 16 18 16 10 12 12

100% 100% 100% 100% 100% 100% 0% 100% 30% 80% 0% 40% 0% 0%

8/1/2009 8/25/2009 10/12/2009 2/22/2012 3/7/2012 3/12/2012 4/28/2012 3/29/2012 4/24/2012 4/3/2012 4/24/2012 3/22/2012 4/8/2012 4/15/2012

Table 2- Villa Milestone 1 sequence

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Actual End Date

Concrete Wall System 2012 7/18/2009 2/3/2010 8/22/2010 3/10/2011 9/26/2011 4/13/2012 Excavation Works Scaffold Erection Window and Doors 2nd Fix Concrete Remedials

GRC Slope Concrete amd Insulation Start Date

Clay Tiles

Duration

Excavation Works

P.C. & R.C. Foundations Scaffold Erection Window and Doors 2nd Fix External Render

GRC Roof Tiles

Figure 33 Gantt chart

Generic Plan of schedule and Construction steps The completion of the villas require several steps building onto each other, therefore the final stage can only be reached through undergoing steps which build on the requirement or process before.

1) For building the structure is needs to be supported on foundations built on a soil, onto which the bearing load can be transferred and which could carry the whole structure. In addition, the structural design includes a basement level below the ground level ďƒ¨ Excavation work to each basement and appropriate foundation level 2) In some Villa slots the soild found was unsuitable to caryy the bearing loads of the structure 9|P ag e

Concrete Wall System 2012  Soil replacement of slot reaching up to 13 layers  Week 13/09/2009: Villa

Actual Layer no. /

no.

Total

117

4/4

119

4 / 13

121

9/9

122

5 /5

124

6/6

3) Construction of P.C. and R.C. Foundation to transfer load of columns onto a larger foundation area, which then transfers the load onto the soil so that it doesn’t exceed the bearing capapcity of the soil  Structure can be built 4) Instillation of Aluminum formwork of the column, outer walls and the stairs of the basement  Cast concrete into formwork and remove after concrete has hardened to have fully finished and poured basement floor 5) Repeat previous step for the Ground floor and later for the first 6) Apply Insulation onto the basement floor before backfilling the excavated hole  Protect from any groundwater or seepage 7) The excavated hole must be filled with solid again reaching to the ground floor level  Backfilling excavation work 8) Repeat the steps for pouring the basement, ground and first for the roof

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Concrete Wall System 2012 ďƒ¨ Use the from work constructed and bought appropriate for the roof form

3) A Safety Assessment of the Site *Found in Appendix B

4) Site Plan *Found in Appendix A

5) Concrete Wall System a. Background Throughout the world, different systems are used for the construction of buildings, which may vary according to the service the building provides, economical issues, aesthetic preferences and many other factors. Such construction systems include timber frames, concrete skeletal systems, steel frames and trusses and load bearing masonry walls, however, the chosen topic handles the case of the concrete wall system.

Figure 34: Various construction systems used throughout the world.

Primarily, a concrete wall system is seen to be very similar to the concrete skeleton structures; however, a closer look would surely emphasize a few differences that make this construction system different than all others. As opposed to providing a working frame for the walls by pouring concrete slabs and columns and infilling them with brick, this system

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Figure 2-2: An aluminum made-to-order construction frame

Concrete Wall System 2012 treats the entire floor of a building as one entity to be poured at once. This means that interior and exterior walls, the floor slab, stairs, columns and beams are treated as one object and concreted all at the same time. This process of mass pouring an entire floor of a building is made possible by the provision of a made-to-order aluminum formwork system, which functions as a mold of the floor with all the openings and dimensions accurately accounted for.

In addition to using aluminum formwork as opposed to the traditionally used timber formwork, this system differs from the traditional concrete skeleton system in that it does not require the systematic sequence of processes of construction of elements; traditionally, columns, beams and slabs are constructed first, and then walls are added, each step requiring a demanding and tedious process of formwork construction and installation which requires quality control at each step of the way. However, in this system, the one-stop installation process means that all these steps are combined into one, reducing both time and possibilities for error.

Figure 3: The use of aluminum formwork for concreting

Although the system utilizes the designed aluminum formwork for the construction of the entire structure, the foundations are constructed through the traditional formwork system, with either plywood or timber being used instead of aluminum. This system is regarded as a deviation from the traditional one due to the material used in form working; however, it is not the only system which uses a different formwork material. Recently, a trend in novelty form working has been taking place, which produced other types of formwork including reusable plastic formwork.

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Figure 35: Arches produced by aluminum formwork in Cairo Festival City

Concrete Wall System 2012 One of the primary reasons behind choosing this construction method lies in the flexibility and speed it provides without sacrificing precision and quality. What this means is that aluminum formwork allows for the introduction of intricate details into concrete that would not otherwise be possible to attain with timber formwork. In addition, it eliminates the errors in dimensions of openings which lead to door and window fitting problems, usually caused by an error in placing formwork of a few millimeters. Also, the speed of construction is increased by around 30 to 50 % over the traditional methods.

In the case of villa construction in Festival City-Cairo, the system was particularly chosen for the accuracy in detail that it provides. As the project features Tuscan and Spanish architectural styles which incorporate a lot of arches in the openings and doorways, the use of aluminum formwork allowed for the fast and reliable production of these opening without the hassle caused by fitting issues.

b. Construction method  Installation i) Installation of formwork Just like the traditional skeleton system with timber formwork, the construction process begins with installation of the formwork before any concreting takes place. The aluminum panels are quite light and the largest component usually weighs around 25-35 kgs, hence no hoisting cranes are needed and the installation is usually carried out by unskilled labor. The sections of the forms are secured in place and pinned together with steel Figure 36: Installation of pins and wedges and usually the only tools required and screws and formwork by pins and a hammer hammers.

In the case of wall, stairs and partition construction, the aluminum installed in double shuttering, this means that both sides of the element are supported so that the concrete can be poured directly in the middle. In the case of roofs, only single shuttering is provided at the bottom of the element to allow for concrete pouring. Sloping 13 | P a g e Figure 37: Single shuttering under roof and double shuttering for beams and columns.

Concrete Wall System 2012 roofs are also constructed with single shuttering, in which case special concrete with zero slump is poured and the workers even out the thickness of the roof with a trowel after pouring.

Usually, insulation foam boards are installed between the formwork on the external side. The internal shuttering section of the double shuttering is secured in place, and then the insulation board is secured in place before the external shuttering section is placed against it. In the local case study, this step did not take place, and the heat gain that would build up due to lack of insulation is Figure 38: Polystyrene board intended on being offset by the use of air-conditioning.

installed for insulation

ii) Concreting After the formwork and decking have been installed, electrical piping and steel reinforcements

are

properly

placed

in

position in preparation for the concreting.

The next step involves placing concrete monolithically in between the formwork.

This step is usually carried out by a boom pump but can also take place using crane or hand bucketing or directly from the concrete truck chute.

Figure 39: Boom pump being used for concreting of floor

iii) Removal of formwork

Figure 40: Before and after the removal of aluminum plates

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Concrete Wall System 2012 Usually this step takes place one day after pouring and perhaps one of the main advantages of this entire system lies in the deck-beam system which supports the formwork. With regards to slabs and stairs, the formwork is usually required to stay in place for a longer time to prevent collapse of the fresh concrete, which would normally cause a delay as this formwork would be required for use somewhere else. However, the deck-beam system used with aluminum form working is designed in such a way that removal of the aluminum panels is possible without disturbance of the supporting deck; after the formwork is removed, the deck and beam are left in place for further support and the panels can be transferred somewhere else to carry on the construction process.

In the case of a multistory construction, scaffolding is constructed after the removal of the external wall panels to provide access to the upper floors. Due to the method of support for the scaffolding, it is used both as a support for the workers on the upper floor and as extended support for the walls. However, this method is not very common and usually regular scaffolding construction takes place.

Figure 41: Metal hangers used to support scaffolding

 Finishing The concrete walls constructed using aluminium formworks are favoured for their high quality concrete finish. The aluminium formwork creates a smooth and consistent surface after removal. It results in “a high quality concrete finish [with]

accurate

tolerances

and Figure 42: Walls, stairs and details of walls smooth finish

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Concrete Wall System 2012 verticality” (Parulekar 27). An “accurate tolerance” indicates one of the main advantages of the concrete wall structure constructed using aluminium formwork and which lies in the benefit of not needing to undergo the process of plastering before applying any cladding or painting.

Normally, the concrete finishes only include a 3 – 4mm skim coat on the internal wall and a 6mm coat on the exterior surface before applying tiles. Due to weather conditions and inadequate work while removing the formwork the upper most level of concrete can be partly removed leaving a roughness Figure 43: Smooth surface finish of concrete wall building

rather than smoothness at parts of the surface.

These holes and rough areas must be overlaid by a very thin layer and mix to ensure one verticality and smoothness on the whole surface. In Malaysia, the dedicated work of the labour and the weather Figure 45: Smooth outer surface of studied project

conditions result in a minimal number of these defected area and therefore only minimal correction work must be done on the surface. To achieve such smoothness an oil was developed in Malaysia and applied onto the formwork so that the formwork can

Figure 44: Floor slab smooth surface finish

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Concrete Wall System 2012 later be removed from the concrete without any difficulties and defaults.

When the same technique was applied at Cairo Festival City in Egypt, the dusty weather cause a layer of sand to get attached to the oil so that while removing the formwork a minimal layer of concrete was removed as well giving the surface an undesired roughness. As a result, the minimal layer and corrections conducted in Malaysia and expected in theory became a whole layer of few millimetres that had to be applied onto the wall surface in Egypt.

Nevertheless, such correction work is minor compared to the usual work of plastering, cladding and painting executed for brick walls. However, even in Egypt these defaults could have been minimized through efficient work conducted by the hired labour.

In the studied project, after removal of the formwork and the correction process either one of two finishes will be applied: 1) Paint A layer of white undercoating will be spread on the whole surface to serve the colour, which will be applied later onto the finish

Figure 46: White Undercoating used on site

ensure that the paint is held in place, remains attached to the wall surface and doesn’t crumble away

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Concrete Wall System 2012

applied paint so as to ensure that the chosen colour is the same as the one on the surface 2) Cladding In our case study, the outer façade could be partly covered with granite tiles instead of paint. These tiles were applied onto the wall using a mechanical fixation, where a layer was applied to hold the granite tile into place.

However, for the tile not to break off the wall or fall off after a while, small steel pins or mechanical keys are attached to the tile and then inserted into the wall to hold the tile in place.

For horizontal application of the granite such as on stairs etc. only a layer of plastering is applied and the granite tile is fixed onto it.

In general, the concrete walls constructed using aluminium formwork create a very smooth surface so that the process of applying finishes is reduced Figure 47: Granite tile with Steel Pins for Mechanical Fixation used on site

drastically making this system very time efficient.

 Equipment For process of excavation and casting of foundation of the studied project the equipment used was: Figure 48: Mechanical Excavator

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Concrete Wall System 2012 1) Mechanical Excavator A comparatively small sized excavator, which is comprised of a boom at the bottom and an excavator arm and upper part attached to it giving the equipment the freedom of rotating the upper part about the vertical axis 2) Bending Machine This equipment is used for bending the steel bars inserted into the foundation as reinforcement 3) Steel Cutter It is used for cutting the reinforcement steel bars to adjust them to the required length and formation of the foundation.

4) Roller Compactor and Small Compactor The roller compactor, as well as the small compactor

are

both

used

for

soil

compaction, where the roller compactor is Figure 50: Roller Single – an equipment driven by a worker with either

Roller Compactor

two or one roller at the front rotating and compacting the soil while the vehicle is moving. The small compactor is pushed manually over the surface to compact and due to its small size is beneficial for Figure 49: Small Compactor

compacting very small, tight areas.

5) Mobile Crane The mobile crane consists of a crane or lattice boom situated on a wheeled carriage, so as to have easy Figure 51: Mobile crane

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Concrete Wall System 2012 transportation on and off the site whenever it is required. The crane usually has a wire rope suspended off of the end of the boom and is designed to carry different loads and objects.

6) Front loader The Front loader is a loader with the shovel located at the front of the vehicle and is used to remove soil and to transport it and load it into a dump truck to be transported off the site.

7) Generator The generator provides electric power for any equipment on site that requires electricity for operation.

For the Construction of the building: 1) Aluminium Formwork The main equipment used for the structure is the aluminium formwork, for which there are several manufactures and types such as “Mivan” and “Framax”. The aluminium formwork Figure 52: Aluminum Formwork system’s main advantage is that the design of the wall and the whole floor including stairs with its details and openings is sent to the formwork manufacturer to construct a formwork unique and corresponding to the design and its details.

The formwork consists of high strength aluminium panels, where the contact surface consists of a 4mm thick plate, “which Figure 53: Aluminum formwork detail of formwork used on site

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Concrete Wall System 2012 is welded to a formwork of specially designed extruded sections, to form a robust component�(Bhattacharya 9).

The formwork sections are fixed to one another using a pin and wedge system, where each panel has an outside rib with holes for the pin to fit in.

The sections are situated next to each other and the pin is put in place passing through the holes of both panels and then a wedge is inserted in the pin to hold the sections and formwork structure in place with the need for bracing.

Figure 54: Pin and Wedge system found in formwork on site

Figure 55: Pin and Wedge Connection System

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Concrete Wall System 2012

For the wall double shuttering is required, where the formwork is installed on each side of the wall to be casted and they are held together using “high strength wall ties�

(Bhattacharya 9). For slabs and the roof only one shuttering is needed, onto which the concrete is casted and which is supported by beams and props.

Figure 56: Wall ties to hold wall formworks together

Figure 57:Props supporting floor slab formwork

Figure 58: Overview of the formwork system

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Concrete Wall System 2012

Even though, the size of the sections, the formwork panels can be easily carried and handled by a single worker due to its light weight thereby excluding the need for any heavy weight lifting equipment on site. The formwork instillation and handling requires semi-skilled labour or even unskilled labour but they need to be educated as to how the system works before starting their work.

“Cairo Festival City”: For our studied project they used the “Mivan” formwork system, an aluminium formwork construction technique developed by a European construction firm and in 1990 the firm “Mivan Company Figure 59: Steel Formwork used on Site

Ltd.” started its manufactory in Malaysia.

(Bhattacharaya

11).

The

supervising

and

construction engineers of the Cairo project visited the manufactory located in Malaysia and observed the work done and the system.

Afterwards the design of the outer walls and stairs of the villa with all the Figure 60: Window detail of "Cairo Festival City"

window details etc. were sent to the manufacturer in Malaysia to construct 6 formworks.

After delivering the formwork to Egypt a number or skilled workers and trainers were sent by the company to hold session and trainings for the Egyptian workers to educate them on how the system works and how to handle the formwork since the system is new for the

23 | P a g e Figure 61: Thin window column constructed with the aluminum formwork

Concrete Wall System 2012 Egyptian Construction field. Later they remained for a small amount of time to observe the work done by the Egyptian workers and ensure the proper work and understanding of the labour.

2) Concrete Pump After erecting the formwork, the concrete is casted into/onto the formwork using a concrete pump found on site.

Figure 62: Concrete Pump

c) Evaluation of System The following table presents a list of pros and cons which were seen after the inspection of the concrete wall construction which uses aluminum form working.

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Concrete Wall System 2012 Pros

Cons

All elements in one floor are poured Does not allow for simultaneous pouring simultaneously which saves concrete in different structures: in traditional pouring and formwork assembly time

systems, the formwork for one element can be used in one building while the formwork for another element can be used in another building. In this case, all elements in one floor are poured at one time and no division between formwork can take place.

Eliminates need for quality check at each If no insulation is provided, concrete step of formwork construction; formwork walls can provide a huge heat gain index of entire floor is set-up and quality check in of installation only takes place once.

extreme

climates

and

cause

discomfort.

As the aluminum panels can be shaped As the aluminum form working is a fairly easily by the manufacturer, the system new form working system, construction allows for a flexibility and great accuracy labor may not be well acquainted with it in detailing of elements.

in parts of the world and their training would prove to be costly

Elimination

of

processes

such

plastering saves on overall project time.

as Fair face concreting does not bond with adhesives

and

requires

additional

mechanical fixation No gypsum boards required for interior Reduced partitioning

flexibility

within

building

interior

When used in a large scale project, the Not cost efficient if used on a small scale system is very cost efficient as the same project; the aluminum formwork is formwork can be used to build various made-to-order and can be very costly if copies of the same prototype 25 | P a g e

not used to construct several buildings.

Concrete Wall System 2012 5) Alternative Methods a. Traditional system 1- Skeleton structure A skeleton structure is designed in such a way that the loads carried are transferred to the slab horizontally; the slab then transfers the load to the columns, the column transfers it to the foundation, and the foundation to the earth (soil beneath). Generally, there are several types of slab systems in which the load transfer path differs: 1) Flat slab: the load travels through the shortest direction to reach the columns. This system is preferred for architectural purposes of dividing spaces.

2) Slab and beam: loads travel in the shortest direction to reach the beam and the beam transfers the loads to the columns.

3) Hollow block slab: similar in concept to the slab and beam system but differs in the composition of the slab as it contains hollow blocks along with secondary beams surrounding the blocks. This method is economically more cost efficient compared to the rest of systems as it has smaller slab widths.

Figure 63- hollow block slab

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Concrete Wall System 2012

2- Formwork The process of creating the traditional skeleton system involves the use of reinforcement steel bars along with concrete (cement, water, sand, aggregates, etc.‌), along with the wooden formwork.

The casting of concrete is done in several steps: -

Wooden formwork is created following the design

of

the

intended

project.

The

formwork is made under the supervision of an engineer and is fabricated and assembled according to the desired size by the site workers.

-

On the other hand, the steel work is also done by other site workers. The steel is the Figure 64- Worker assembling the steel reinforcement bars

first to place within the formwork. The formwork is used whenever the casting of concrete takes place, to create the boundaries in which the concrete will be cast to form various elements of the building (slabs, roofs, columns, beams, foundations, bearing walls or shear walls). They are the containers of which the concrete takes the shape.

-

The worker on site works on creating the Figure 34- Concrete poured in directly on the

formwork by compiling the wood together using steel reinforcement pins, and joints to hold the different of the many

pieces of wood all together. This process is often time consuming and is limited in the sense that it does not provide a high accuracy since the wood is assembled on site and thus the formwork is subject to human mistakes.

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Concrete Wall System 2012 -

The worker on site is responsible for creating the designed reinforced bars by bendi ng, joining, and attaching them all together, to place within the formwork. After that, the concrete is to be poured on top of the steel re-bars inside the formwork.

-

This process involves several workers that work on spreading the concrete and compacting it to make sure that the formwork is completely filled with no voids and that it has a flat surface.

-

After the casting is complete, the concrete is left within the formwork to dry and harden (a curing process is required to ensure the best strength of performance of concrete).

-

After this period the formwork is

Figure 35- Workers spreading the concrete to create a smooth surface

removed, to be used once again in casting the next components.

3- Walls After the skeleton structure is complete, masonry or bricks are used to create the walls of the building: The bricks are held together by cement mortar and they are compiled next to each other and on top of each other according to the design of the building, and under the supervision of the engineer who will make sure that they are located in their proper location according to the floor plans, and that the openings are in their accurate position. Since the openings in the walls are done manually, they are usually not very Figure 36- Construction of precise. However, the use of bricks gives the advantage of

walls using bricks and cement

flexibility as they can be easily removed and placed instantly. The use of double layer masonry wall is possible in exterior walls, which can be better for heat insulation. A

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Concrete Wall System 2012 plaster layer is used to cover the masonry and is applied by a site worker and is flattened ready for exterior finish layer (paint, stone cladding, marble, granite, plaster etc.… ).

b) Precast Concrete Walls “Precast maximizes the benefits of concrete by adding the many benefits of off-site

construction. The ability to manufacture high quality, dimensionally accurate precast units in controlled factory conditions are just some of the benefits. Speed of construction, the reduction of waste and the provision of safe working platforms are other features of precast.” (Irish Concrete) Many types of installation techniques according to different types of Precast Concrete, the engineer choose whether to use this system or not according to different criteria including project type, timing, finishing (appearance) and cost.

The Precast concrete system is mainly known for its speedy and efficient process; also aesthetics and cost are two of the major characteristics of precast concrete. The idea of precast panels is being manufactured well before the installation and could be called by the contractors at short notice. A Typical Precast Concrete wall panel could be requested in all dimensions with any architectural features, as shown in the image to the left. Standard dimensions vary. Precast concrete panels could also be manufactured on site right before installation, like tilt up panels.

Figure 65- Precast Wall Panel There are two main different methods of attachment of Precast Concrete Members, those include protruding Reinforcement bars, in situ concrete at connections, welding and grouting.

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Concrete Wall System 2012 a. Welding: In this method, the precast members ordered have steel plates embedded to act as the welding surfaces where the loose plate will take place, as shown in the schematic below.

Figure 38- Welding of Precast Members

Figure 39- Installation of a precast wall welding system New Zealand (A. Charleson)

Embedded Steel plates

b. Grouting:: Normally used when installing a precast concrete slab, the grout fill as shown in the schematic is added, the rebar grouted in place, holding the beam or wall together with the slab.

When comparing this system with the concrete wall system, a variety of aspects are considered, starting with Time; time efficiency in both systems are available, although in precast systems its more rapid since there aren’t any concrete pouring and setting time, the panels are called to order and installed in place. Regarding quality in manufacturing, the precast concrete system is of consistent quality; standard deviations would be minimal since

Figure 40- Precast concrete wall system

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Figure 41- In situ Concrete wall system with openings (wood formworks)

Concrete Wall System 2012 the concrete is casted off site and in large amounts in controlled conditions. Finishing quality is very similar in both systems, as mentioned earlier; the precast systems are manufactured with architectural features (openings, doors, etc.) while the concrete wall system has unique shapes of formworks that suits the properties of openings required, and is used while pouring, this process although needs special trained workmen brings out a very good quality finished openings and surface.

Figure 42- Installation of Aluminum Formwork used in Cairo Festival City (Local Case study) before pouring concrete fences.

A problem with precast concrete walls is having a limited span, therefore not as flexible as pouring concrete in situ and using formwork, also this feature limits the precast panels to one way structural systems. Regarding cost, precast panels connections and joints are expensive and complicated, resulting also in skilled labor throughout the installation process.

While Concrete wall systems need formworks to be poured in, equipment used in installing precast concrete members, are cranes, as shown below.

Figure 43- An example of a precast panel lifted to final placement with a crane

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Figure 44- an example of in situ concrete pouring through a tube from a pump truck in a project in Serbia

Concrete Wall System 2012 To sum up, Precast Concrete System is most commonly used when very rapid construction process is needed, in a precast wall panel system, the panels arrive to the site, cranes start lifting them up in place while the workmen start connecting them together and in one day a number of floors could be lifted. It’s a very fast process which lessens in return the construction phase and financial costs. The in-situ concrete wall and slab system adapts to any building shape, therefore more flexible than the precast system, it does not require cranes in the construction process, use of formworks results in very accurate and good quality finishing. No joints or connections are needed.

Figure 45- The Precast House in Howth Village by FKL Architects

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Figure 46 - Concrete Wall System in Cairo Festival City, New Cairo

Concrete Wall System 2012 6) Production Rate 

Theoretical

The “Mivan” system undergoes a “four day cycle” for constructing a floor, where the first day consists of erecting the vertical steel bars and the formwork for one side of the wall. The second day the other part of the wall formwork is erected as well as the formwork of the floor slab and stairs. The following day includes the fixing the reinforcement steel bars and pouring the concrete. After 24 hours the wall formwork while keeping the floor slab formwork for another 2.5 days and the props for 7 days as support.(Bhattacharaya 23) The erection of wall formwork takes about 7 hours but the reinforcement and location of electrical boxes and outlets and other details result in a 7 day period for the concrete to be casted. After that period another 24 hours and more as is explained above is needed before removing the formwork and reusing it. This estimate is calculated for a project with formwork size 1010 – 1080m2 . As a result the aluminium formwork method results in a time saving of almost 10 – 15 days compared to the conventional system to reach a fully constructed structure. In a project having 16 high-rise, residential buildings, conducted in Mumbai, India in November 2003 using the aluminium formwork each floor was fully constructed in only 4 days. (Bhattacharaya 28) However, this time estimate is only to compare the final structural phase of having a complete concrete structure but doesn't include the finishes that need to be applied to the building. As mentioned above the aluminium formwork leaves a very smooth and high quality surface behind so that paint can be applied immediately after removing the formwork completely without needing to undergo the process of plastering etc. as in conventional 33 | P a g e

Concrete Wall System 2012 construction. Therefore, the above mentioned difference in construction time will be magnified due to the much lower finishing time required for aluminium formwork finishes.

Therefore, one of the main advantages of the aluminium formwork construction system is its time efficiency and speed of construction and finishing the project while maintaining a high quality end result. This advantage was also one of the main reasons “Al Futtaim Group” chose to use such a construction technique in its large scale project.

In our case study of “Cairo Festival City” the estimated time required for fully constructing one villa was about 1 month taking into consideration the inefficiency of the workers and their slower pace in working since the system was a totally new construction technique for the Egyptian workers. This time period didn't differ as much form the time period for the conventional system. However, the speed of applying finishes for the “Mivan” system used was estimated and resulted in a much lower construction time than the conventional system.

Actual The theoretical data and estimates for “Cairo Festival City” turned out to be very far away from the actual end result. The area of villa’s we studied and observed was divided into 7 Milestones or phases of constructions. The first Milestone included delivering 23 villas of a total of 172 villas on the whole area of the Milestones. According to the old biweekly reports excavation started on the first plot of Milestone 1 on 28th June 2009 and the whole Milestone was scheduled to be delivered on the 21st of January 2010, while all 7 Milestones were estimated to be delivered on the 15th of June 2011. However, after visiting the site and talking to the responsible site engineer we found out that today from the 23 villas only 19 were fully constructed and the phase of applying the finishes was still in process. This delay

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Concrete Wall System 2012 of almost 2 and a half years for only the first Milestone excludes the advantage of construction speed assigned to the aluminium formwork construction system.

Such a delay compared to high speed of construction in other international projects is due to several reasons: 1) Unreliable Workers The workers hired for the project needed to undergo an intensive training held by officials sent by the manufacture to get familiar with the system and understand it since the “Mivan� system is a new construction technique for the Egyptian worker.

However, most of the hired labour get paid on a daily basis and several of the trained workers left the project unannounced for a project with higher daily wage. As a result the contractor needed to undergo the process of training the labour before sending them into the field another time, delaying construction work until qualified labour was found to work with the full potential and speed again.

2) Inefficiency of workers The Egyptian workers compared to the labour observed by the responsible engineer for the project in Malaysia and India are inefficient and do insufficient work. The Egyptian worker due to his work attitude and other factor delivers results having several defaults and malfunctions. These mistakes must undergo a process of correction or even reconstruction of certain aspects and building parts, which results in a delay of the whole building 3) Insufficient number of formworks The villa area we studied was designed to be constructed using 6 formworks, which meant that the 172 villas needed to be divided onto 6 lines of work. As a result a 35 | P a g e

Concrete Wall System 2012 delay in any of the villas would cause a delay in the whole line of villas / work scheduled to be constructed using that same formwork. Therefore, the delay of a building due to malfunctions would also detain any work done on any other villa in that same line of work, which in return caused that magnified time delay for the whole villa area.

7) Quality Control In-situ concrete work is affected by site conditions and requires strict quality control (ADAS). Quality Control is conducted on the concrete wall system to ensure durability, consistency and fulfilled requirement, the system consists of two main parts, the infill; concrete and the formwork.

A. Concrete

Figure 47: The slump test ASTM C-143

Figure 48: Concrete Cube Strength testing

Figure 49: An air meter ASTM C-231

General tests to ensure the good quality of concrete is first to check the materials, the aggregates should confine to ASTM C 33, which includes the standard specifications for aggregates, including gradation, texture and shape. The engineer could ensure the good 36 | P a g e

Concrete Wall System 2012 workability of concrete through a very simple test, slump to know whether the batch weight of the mix consistent or if the water/cement ratio proportionate (ASTM C-143). Also this test gives a slight indication on whether the concrete needs admixtures. Building in extreme climates, hot or cold, puts concerns on the aggregate moisture content as well as over all workability, therefore testing the concrete sample under existing climate conditions will indicate many important criteria or guide lines in modifying the mix design to suit the conditions available. Air content, or the amount of air voids in the concrete design batch should confine to a certain range according to ASTM C-231, therefore an air meter with a vessel calibrator equipment is used to measure the amount of air in the concrete sample, another test that could measure air content by elimination is the unit weight test (ASTM C138). Concrete mix designs should be tested for their compressive strengths. According to BS, the test is conducted by pouring three cubes of concrete and recording their average strength over different intervals, 7 and 28 days. (Concrete Network). Setting time of concrete is directly related to the sample’s specifications, in terms of w/c ratio and slump, therefore a vicat needle is set to penetrate through a minimal sample of the concrete batch and initial and final setting times are recorded in the lab indicating the overall behavior of the concrete.

In the local case study conducted, Cairo Festival City’s Quality Engineer explained how the concrete batches were tested for performance before casting; this testing process normally takes place close to the site in the Concrete pumping station at the borders of the land which saves them a lot of transportation problems.

Necessary equipment used for concrete works testing included;  Balance with 0.1 GM, accuracy  Balance 30 KG capacity, 1 GM, accuracy.  Oven  Wheelbarrow  Square Shovel  Vicat needle apparatus  Thermometer  Flask, Volumetric 2000 cm3 37 | P a g e

Concrete Wall System 2012  Sheet Metal Cubes 15x15x15 cm with damping rod  Sieves, standard sets  Cubes testing machine 2000 KN  Slump cone set with damping rod and plate  Small tools (trowel, mixing pans, mallet, wood float, scoop, etc…)

The job site laboratory is headed by a laboratory engineer and assisted by two laboratory foremen. Laboratory trained laborers are also available for collecting samples at site and performing slump tests on fresh concrete.

Forms for the laboratory: 

Pouring Report



Concrete Sample Register



Concrete Compression Test Report



Daily Report for pouring Concrete

*Refer to samples of each form in Appendix A

B. Formwork Pouring of concrete in this system is more or less an act of filling the formwork structure erected, thus the quality control of the formwork and its properties are of utmost importance to ensure the quality of the whole structure.

Formworks are first inspected by the quality engineer to ensure the consistency of dimensions (MIVAN). During formwork installation, the quality engineer ensures the accurate placement and Figure 50: Typical Formwork setup for a concrete wall

fixation to the ground, with different connection according to the formwork system.

After fixing the formwork rigidly to maintain the concrete wall shape required. Approval

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Concrete Wall System 2012 to the contractor is sent and the pouring of concrete starts. Following the casting, the formworks are erected carefully by unskilled labor.

In Cairo Festival City , the quality control procedures to the formwork are divided into three phases; those done pre-concrete activities, during concreting and post concrete activities.

1. Pre-concrete Activities: Aluminum MIVAN forworks were imported according to amount of pallets needed. Formwork shapes included those of the irregular openings, such as arch heads as well Figure 51: Engineer inspecting the joint connection in the erected formwork

as the regular windows. The unloading process is supervised by the quality engineer, to make sure there

aren’t any missing items in the stacks received. A confirmation of materials received document is submitted to the contractor each time a new stack is received (Refer to Appendix A for a copy of the document).

A concrete level survey should be taken on all sites and remedial work carried out prior to erecting of the formwork. A record of all survey should be kept on file by the allocated supervisor. Kickers are manufactured with a 26 mm slotted hole on the face to allow for adjustment after concreting.

The setting out process are done through the approved shell drawings by Mivan Formowork Design. Setting out lines should continue through openings, external corners, etc‌ by a minimum of 150 mm, in order to make it easier to fix the formwork in position prior to concrete pouring. A study of the deviation and kicker level survey should be done to know if corrective action is required.

For the initial set up only, 50 mm x 25 mm timber stays can be nailed to the concrete slab, close to the internal an external corners, to ensure the formwork is erected to the setting out lines. Ensure all edges of the formwork and contact face are properly

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Concrete Wall System 2012 cleaned and oiled prior to fixing in place. Wall ties should be coated with the releasing agent provided before being fixed to the formwork.

A pre-pour check list is conducted well before the pouring approval, refer to appendix A. 1. During Concreting: Two operatives should be on stand by during concrete pouring, to cover both sides of the wall being casted. Best position is slightly in front of the pour, checking pins, wedges, and wall ties during the pour.

2. Post Concrete Activities: Before striking wall formwork ensure those are removed:

Timber stays nailed to the concrete slabs



Walers



Vertical soldiers



All pins and wedges

3. Post Concreting Activities: Struck wall formworks should be cleaned with scrapers

and

wire

brushes.

Regarding

the

formworks transportation, the full height wall panels could be carried through the nearest stairway or passed up through void areas. *Refer to appendix B for sequence of erecting formworks in schematics

Figure 52: Formwork at Cairo Festival City

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Concrete Wall System 2012

8) Safety Requirements The following safety precautions are, in theory, some of the most important hazards and regulations to be followed by everyone in the construction process of the project.

I- Work permit system The project work permit system is implemented in all construction areas of the project in order to ensure that all the hazards are identified and that the risks are properly assessed and controlled. The implementation of this system is a must when it comes to maintaining a safe work environment, and is a requirement for all client jobs in existing facilities.

There are four types of work permits: 1- Hot work permit This applies to jobs or works located inside areas that contain flammable or combustible materials that may generate one of the following: -

Naked flame

-

Electric arc welding

-

Pre-heating and electrical stress relieving

-

Opening live electrical junction boxes panels

-

Use of steel wire power brushes

-

Abrasive blasting and painting

2- Cold work permit This permit applies to work involving one or more of the following: -

Handling of dangerous substances (e.g. Toxic chemicals, flammable materials, etc.‌)

-

High pressure water jetting

-

Chemical cleaning

-

Wet shot/ grit blasting

-

Work at high level above ground

-

Digging of deep foundations/ trenches, etc.‌

-

Any work directly affecting the operation of emergency systems

-

Persons working over the side or under scaffolding

-

Pressure testing of plant or equipment

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Concrete Wall System 2012 -

Maintenance activities for electrical and mechanical isolated equipment

3- Confined space entry permit -

Work inside a non ventilated area, tank, or vessel, where dangerous concentrations of toxic, flammable or hazardous gases, fumes or vapors could arise, or where the oxygen content of the air could be reduced to 20% by volume.

-

Issued by area authority after completion of pre-permit work

-

Is it mandatory to apply a gas test

-

An attendant should monitor the entry of personnel in the confined space at all times, using the confined space entry log

4- Excavation work permit -

Required to ensure that all necessary precautions are taken to avoid damage to underground services like electrical cables, piping, instrumentation and telecommunication

-

Usually accompanied by a hot or cold work permit

II- Personnel protective equipment 1- Head protection Safety hats or helmets are made of materials that are designed to protect the head from impact, flying particles, electric shock... Each helmet consists of a shell, a suspension cradle, and a chin strap.

Helmets are color coded in the following manner: - White color: Engineer - Grey/ Blue: Supervisor - Red: Safety security staff - Green: Visitors - Yellow: All other workers on site 2- Eye and face protection - Face shields to protect the face and neck from flying particles, sprays of hazardous liquids, and hot solutions.

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Concrete Wall System 2012 - Safety spectacles should be worn under the face shield if urgent, and it is highly recommended to avoid the wearing of contact lenses in areas where eye protection is required.

3- Hand protection The wearing of the right type of gloves is an important matter during the construction and operation phase, so one should select the right kind of gloves depending on the materials or the equipment being handled. Gloves can be resistant to the following: - Heat - Acid - Caustic - Slipping - Wear - Fire - Oil - Sharp edges - General tear and wear Gloves should not be worn near moving machinery since they can be caught and trap the hand before the hand before it can be withdrawn from the glove.

4- Foot protection Foot protection is necessary to prevent injuries when accidents occur. Comfort is also an important matter so the safety footwear should fit the wearer properly.

Generally, the approved type of footwear consists of leather uppers and/or leather composition with steel toe caps.

5- Hearing protection

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Concrete Wall System 2012 - Hearing protection devices are provided and used in case of exposure to more than 90 db. Ear plugs can be made of rubber, plastic, wax, foam or Swedish wool and disposable types are preferred as they give good protection and are very sanitary.

- Ear muffs cover the external ear to form an acoustic barrier.

6- Fall protection devices - Harnesses are used for above ground work where fall restraining and arresting protection is required.

- Safety belts are not considered as part of the fall arrest system at heights larger than 10m above the ground.

- Full body harnesses may be required in areas with no guard rails at heights above 1.80m.

- All users should be aware of the importance of a firm anchorage.

- Fall protection devices should be stored in clean and dry conditions and away from sunlight and must be regularly inspected both on issue and at the start of each shift.

- Any worker working at a height of 1.80m above ground without the protection of a guardrail system should wear a full body harness III- Hand and power tools Hand tools are tools for which the main force is provided by hand. Examples of hand tools are picks, shovels, axes, crowbars, wrenches, saws, chisels, hammers, and screwdrivers‌ Power tools are tools operated by power supply, such as grinding machines, drilling equipment, etc. The precautions that should be taken when using hand and power tools are the following: -

SIAC and construction subcontractors’ workmen shall be instructed to select and use the proper tool for a given job.

-

The use of power tools comes after the proper training of workmen, proper maintenance, and by adequate site supervision

-

All hand tools should be inspected regularly before and after use, and before storage. If wear or damage is observed, the tool should be kept from usage for repair or disposal

-

In areas where work takes place on or near electrical operations, only properly insulated and non-conductive tools should be used

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Concrete Wall System 2012 -

All portable power tools should be stored in clean and dry conditions

-

SIAC and construction subcontractors should provide a schedule of inspection and maintenance for all power tools

-

Power tools are not to be left lying around the site, since they could be damaged.

-

Tools must be disconnected before changing bits, blades, or wheels

-

All personnel should be equipped with the proper protective equipment during the use of these tools

-

A protective guard should come with all grinders to allow only the working part of the grinder to be exposed, and should not be removed

-

Operators should wear the proper eye and hearing protection when working with wood cutting

IV- Ladders The use of ladders is one of the most hazardous activities done on site, and the following instructions are to be followed when using ladders: -

The ladder must be of proper length for the job

-

Metal ladders, ladders with metal side rails and wet ladders should not be used near electrical equipment with exposed live conductors. Aluminum ladders should not be used where there is a risk of contact with materials harmful to aluminum, like caustic liquids, damp lime, wet cement, etc.

-

Damaged ladders such as ladders with split or broken side rails, or missing, broken, loose, decayed, or damaged rungs or cleats should be kept away from use

-

The area at the base of a ladder should be kept clear

-

Ladders should not be used in a horizontal position as platforms, runways or scaffolds

-

Ladders should be set at an angle forming 75째 with the horizontal (i.e. one meter out to four meters up)

-

Ladder landings should be located at least every 9 m of height and should be fitted with a guardrail system and toe-boards

-

Workers should not run up or down or slide down a ladder at any time

-

Workers ascending or descending ladders should not carry tools or materials in their hands and tools may be carried in pockets

-

If the job being done requires the use of both hands, one must put a safety belt, securely fixed to a drop line (life line). Only one person should use the ladder at a time

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Concrete Wall System 2012 V- Scaffolding -

Work done at a height higher than 1.8 m should be done using scaffold

-

Scaffold should be provided with the following requirements: base plates, platforms, ladder, tagging system, handrail, mid-rail, toe-boards, bracing system

-

The tagging system is an indicator of the safety of the scaffold; a green scaff tag means that the scaffold is safe to be used; a yellow scaff tag means that the scaffold is to be used but using harness safety belt; a red scaff tag means that the scaffold is unsafe to use and it is under construction

-

Scaffold inspection checklist should be used on site

-

For scaffolds higher than 3.0 m, workers should be protected by guardrails and a personal fall protection system (PFPS)

VI- Electrical installation and equipment -

Cables on site are subject to rough treatment. Special attention should be taken to ensure that the grounding conductor stays intact. If the conducting wire breaks the system will no longer be safe

-

All installation work must be done by qualified and experienced electricians

-

All non-current carrying metal parts of electrical equipment have to be properly grounded, in order to reduce the electrical shock hazard

-

Employees must never work on live equipment alone, a supervisor and an electrician must be standing by

-

Exposed buried cables in open trenches must be supported and the area barricaded

-

The power generator should be: 

Rated to meet the maximum anticipated load



Located in an enclosed and ventilated area



Provided with proper silencers to control noise emission

VII- Mechanical equipment 1- Compressors -

Employees should never use compressed air to dust off clothing or machinery

-

Employees must wear goggles and full face shield when using compressed air for cleaning and purging tasks

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Concrete Wall System 2012 -

Before start up, a daily check should be made on the compressor’s pressure relief valve, fuel, oil and water levels and the air reservoir should be drained of trapped water

-

The air should be periodically tested in order to make sure it is safe to breathe

2- Excavators -

An attendant must be available at all times during the excavation process to guide the operator and assist him when needed

-

Excavators with swinging motion should have a clearance distance of at least 0.6 m from any fixed object

3- Fork lift trucks -

A special course of instructions should be attended by all forklift drivers, and they should not be allowed to use the vehicles unless they have completed the course

-

Operators, loaders, and other workers should never place any part of their bodies between the mast uprights , cross members, or other moving parts of the fork lift truck

4- Power generators -

The side panels of the engine cover must be closed at all times while the engine is running

-

All fuel leaks must be repaired

-

Hose and pipe connections should be checked for wear and cracks

-

It is prohibited to place sheds made of combustible materials around generators and wooden base frames

-

Generator sets should be placed at least 50 feet from buildings and materials that might catch fire

-

Fire extinguishers should be accessible. A CO2 extinguisher should be available for the generator and a dry chemical extinguisher is recommended for the engine drive

5- Graders, dozers, scrapers, loaders and mini loaders -

Workers are prohibited from sitting or lying in the area around the machine

-

The engine should not be left running when the driver is not inside

-

Blades, scraper bowls, etc. must be lowered to the ground before the driver leave his unit

6- Wood working machinery -

Only authorized and trained personnel are permitted within the barricaded are around saws, planers and routers

The ground around these machineries should be kept clear from off-cuts and other tripping hazards 47 | P a g e

Concrete Wall System 2012 Reference "Concrete Wall Forms." Wall-ties and Forms. Wall-ties&Forms, Inc., Nov 2004. Web. 14 May 2012. <http://www.wallties.com/concrete_forms.htm>.

"Concrete Pouring." Eco Blocks. Eco co., Mar 2008. Web. 16 May 2012. <http://www.ecoblock.com/product/pdf/manual/10_Concrete_Placement.pdf>.

"Installation Manual." Polysteel. Building for a better world. American Polysteel, LLC, May 2005.

Web. 14 May 2012.

"GEM Ontology & Taxonomy." Precast Concrete †” GEM Nexus. Web. 21 May 2012. <http://www.nexus.globalquakemodel.org/gem-ontology-taxonomy/buildingtaxonomy/glossary/precast-concrete>.

"Engineering Projects." Mivan Formwork-Aluminium Formwork. Web. 21 May 2012. <http://www.architectjaved.com/mivan-formwork/aluminium_formwork.html>.

"Quality Control for Precast." Precast Concrete Quality Control. Web. 21 May 2012.

"Precast Concrete Construction." Precast Concrete Construction. 21 May 2012 <http://faculty.delhi.edu/hultendc/A220-Week5-Lecture.htm>.

"Lecture9." Mcgill. 21 May 2012 <http://www.arch.mcgill.ca/prof/friedman/arch240/winter1998/lecture9/lecture9. html>.

"News." Beodom. 21 May 2012 <http://www.beodom.com/en/news/entries/making-ofamadeo-ii-underground-parking-walls>.

"ASTM and the Concrete Contractor." How ASTM Standards Affect the Contractor. 21 May 2012 <http://www.concreteconstruction.net/specifications/astm-and-the-concretecontractor.aspx>.

Parulekar, N. “ Aluminum Fromwork Systems: An Emerging Trend”. Metalworld. November 2012: p 26 – 30. <http://www.metalworld.co.in/newsletter/nov10/perspective1110.pdf>.

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Concrete Wall System 2012 Appendix A i. ii.

Hazard Report Pouring Report

iii.

Concrete Sample Register

iv.

Concrete Compression Test Report

v.

Daily Report for pouring Concrete

vi.

Pre-pour checklist

vii.

Confirmation of materials Received

viii.

Bi-weekly reports

*Available in Hard Copy only (certified Form samples from site office)

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*Rest available in Hard Copy only (certified Form samples from site office) 52 | P a g e

Concrete Wall System 2012 Appendix B 1) Formwork Erection Sequence 2) Site Plan (to scale)

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