TABLE OF CONTENT

Cover Page 1

Table of Content 2

1.0 Introduction 32.0 Objective 43.0 Content / Technical Observations 54.0 Foundation 6-7

4.1 Bored Piling 8-95.0 Reinforced Concrete 10-126.0 Conclusion / Learning Outcome 137.0 Photos 14-25

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1.0 Introduction

In this assignment, we were required to produce a report on the construction site visit for combination of 3 subjects which are Building Materials, Construction Technology 1 and Measurement 1. It was organized by our Measurement 1 lecturer, Sr. Ang Fuey Lin.

On 26 June 2015, about 57 students attended the site visit. We were to be divided into two groups. Group one contains 28 students where everyone needs to be there outside the site at 9am sharp whereas group two contains 29 students where everyone needs to be there outside the site at 10am sharp. We were required to wear safety helmet, long pants and sport shoe/safety shoe while visit the construction site.

When we started our site visit, we were given a brief talk about the safety and rules at the site. Then we kicked off our site visit. Our site visited was leaded by a site contractor. He explained information of the building briefly and clearly.

Below shows part of the progress report taken from Transpace Builders Sdn Bhd

- Contract Particulars:

Suggestion to build 2 blocks of condominium (353 units) and 22 units of villa (3 floors each) at lot 515, off Jalan Puchong for the client Pola Aman Sdn

- Scope of Works:

Site Clearance, earthworks, construction of bored piles and pile caps works Construction of basement slab, beams, retaining wall and ground floor slab

including column lift wall, ramp and staircases starter bars from basement to ground.

- Client : Pola Aman Sdn Bhd

Architect : T & T Architect Sdn Bhd

Civil & Structural : Perunding LNL Sdn Bhd

Quantity Surveyor : CPK Associated

M&E Engineer : Perunding ISD Sdn Bhd

Piling Contractor : Transpace Builders Sdn bhd

The main objective of this site surveying is to expose students to the construction process especially the pile foundation.

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2.0 Objective

The objectives of the site visit are:

To let us experience the actual working environment and learn more about the life of being an Quantity Surveyor on site.

To allow us to have a better understanding of the types of the building materials involved in the construction site.

To aware the important of taking care of personal safety and the safety precautions that may lead to accident.

To enable us to understand the building structure and the sequence of constructing a building.

To gain more construction technology knowledge that are new to us. To make it easier for us to get clearer image of how the structures look like in real

life. To make us understand the important of teamwork and communication skills while

working together with the construction team such as engineers, project managers, contractors and workers.

To observe the usage of the construction equipment on site such as crane and bar bending machine.

To understand the basic of the construction process Understand the basics of the construction process.

To understand the practical aspect of construction techniques in comparison to the theory aspect in books and its application on site.

Exposure to actual working environment on site including uncertainty circumstances e.g. weather.

Ability to communicate with the construction team members on site and to see the importance of teamwork in the building team.

Witness the usage of construction equipment on site including mechanical plants. To explore and identify various types of building materials and technology on site. Awareness of the importance of safety on site and understanding of safety problems

and site conditions. To recognize the items measurable for sub-structure and reinforced concrete frame

works.

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3.0 Content / Technical Observations

When we reached the construction site, I saw a project information board that was placed outside the fence. The function of the project information board is to state the role of each constructor involved. Moreover, there are a few temporary works installed at the site which are accommodation for workers, material storage, security and scaffolding. The whole area of the construction site is fenced by vertical hoarding. It is a close-boarded fence to prevent unauthorized persons access to site. It can also be used to resist wind loads and fixed by stays to external wall. Furthermore, a temporary material storage can also be found at the basement to store materials.

Around the surrounding area of the structural buildings, there exists a few independent scaffolding with safety net cast around it to protect people from falling down by limiting the distance they fail. It is used to support people and hold materials that are to be used for construction or repair of buildings and other structures. It aided the safety of the workmen and allowed easy access to areas that are difficult to reach. They are constructed by using metal tubes with metal platforms. Besides that around the inner part of the scaffolding, they have cleverly installed a series of stairs for the purpose of easy movement of workers up and down the building structure.

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4.0 Foundation

The foundation used in this construction is the pilling foundation. The construction site had chosen the piling foundation due to the height of the building constructed which consists of 30 floors. Piles are deep foundations that are being driven into the ground in situ which involves the process of excavation and drilling. These pile foundations can be made out of pre-stressed concrete, reinforced concrete, steel and timber. For this construction site, the reinforced concrete is also being used.

Pile foundations are deep foundations. They are formed by long, slender, columnar elements typically made from steel or reinforced concrete and sometimes timber. Piles are normally used when the subsoil condition is weak, because it provides great load bearing capacity. Pile foundations are principally used to transfer the loads from a superstructure, through weak, compressible strata or water onto stronger, more compact, less compressible and stiffer soil or rock at depth, increasing the effective size of a foundation and resisting horizontal loads. They are used for large structures, and in situations where the soil under is not suitable to prevent excessive settlement.

There are two categories into end-bearing piles (where most of the friction is developed at the toe of the pile, bearing on a hard layer) or friction piles (where most of the pile-bearing capacity is developed by shear stresses along the sides of the pile, suitable when harder layers are too deep).

- End Bearing Piles

The toe of the pile lies on a layer that has strong soil or rock. The superstructure’s load transfer through the pile onto the later beneath the toe pile. These loads passed through a layer of weak soil and safely transferred to a stronger layer. If a bedrock or rocklike material is present at a site within a reasonable depth, piles can be extended to the rock surface. In this case, the ultimate bearing capacity of the pile depends entirely on the underlying material; thus the piles are called end or point bearing piles. In most of these cases the necessary length of the pile can be fairly well established. Instead of bedrock, if a fairly compact and hard stratum of soil is encountered at a reasonable depth, piles can be extended a few meters into the hard stratum.

- Friction Piles

The superstructure’s load is being transferred across the full height of pile through friction. It works on a simple principle of pushing a metal rod into a frozen ice cream. Once pushed in, it is strong enough to withstand certain load similar to the friction pile. These piles are being connected by a pile cap which is made of concrete and being embedded to the piles acting like the head of the pile. This can help distribute the loads which are being transferred by the super structure. In these types of piles, the load on pile is resisted mainly by friction resistance along the side of the pile (pile shaft). Pure friction piles tend to be quite long, since the load-carrying. In cohesion less soils, such as sands of medium to low density, friction piles are often used to increase the density and thus the shear strength. When no layer of rock

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or rocklike material is present at a reasonable depth at a site, point/end bearing piles become very long and uneconomical. For this type of subsoil condition, piles ate driven through the softer material to specified depth.

Pile foundation is able to provide sufficient bearing capacity and strength especially for tall buildings.

To select the suitable foundation, several applications are needed to be considered:

Accessibility Condition of ground Nature of the load requiring support Proximity to other structures Sensitivity to noise and vibration Water table

Before the installation of pile foundation, there are factors that need to be observed:

Available space and head room on the site Availability of cranes Noise restrictions Size and weight of pile

Advantages of Pile Foundation

Able to place deep into the soil Can be precast to the required specifications High load bearing capacity Progress of the work will be rapid, neat and clean Suitable for weak soil

Disadvantages of Pile Foundation

Advance planning is required for handling and driving High initial cost Precast or prestressed concrete piles must be properly reinforced to withstand

handling stresses during transportation and driving Requires heavy equipment for handling and driving

There are several methods of pile driving:

Dropping weight Explosion Jacking Jetting Vibration

4.1 Bored Piling7

Bored pilling is used for the construction. Bored piling is a method that involves boring a circular hole into the ground, installing steel reinforcement and filling the bore hole with concrete to form a pile. Boring is carried out to the required depth by means of either a crawler crane-mounted rotary boring unit or a purpose-built hydraulic drilling machine. Bored pile foundations are suitable for all types of soil conditions and compared with conventional driven piling methods, bored piling activities generate less noise and vibration. Bored piling is popular to be used in construction as a foundation, especially for bridge work and tall buildings as well. Bored piling work has to be done by specialist bored piling contractor, normal piling contractor cannot execute this type of work without experience and knowledge about bored piles.

Bored Pile Procedure:

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1. Set up the Location of Bored Pile

2. Insert Casing

3. Drilling

4. Removing Slime

5. KODEN-Test

6. Insert of Steel Cage

7. Insert Tremie Pipe

8. Pouring the Concrete

9. Removing Casing

Advantages of Bored Pile

Piles of variable lengths can be extended through soft compressible or swelling soils, into suitable bearing material

Piles can be extended to depths below frost penetration, and seasonal moisture variation

Large excavations and subsequent backfill are eliminated Adjacent soil is not disturbed or remolded Absence of vibration will not disturb adjacent piles or structures Extremely high capacity caissons can be obtained by expanding the base of the shaft

up to three times the shaft diameter, thus eliminating construction of caps over multiple pile groups

For many design situations bored piles offer higher capacities with potentially better economics than driven piles

Eliminates the constructions caps by expanding the base of the shaft, also to obtain the high capacity of caisson

Flexible size to suit different type of loading and subsoil condition Produced low noise and vibration

Disadvantages of Bored Piles

Concrete is not placed under ideal conditions and cannot be subsequently inspected Susceptible to “wasting” or “necking” in “squeezing” ground Water under artesian pressure may pipe up pile shaft washing out cement

5.0 Reinforced Concrete

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Different grades of concrete are used for different construction. The grades of concrete refer to the mix ratio of the concrete.

Foundation Grade 35Column Grade 45Slab Grade 35Wall Grade 35Beam Grade 35

Grade 35 and 45 used at the construction side thus comes under the category of pre-stressed concrete. This pre-stressed concrete possesses great strength which is suitable for buildings that has heavy load. Pre-stressed concrete’s internal stresses are distributed into suitable magnitude so that stresses from the external will counteract with the internal stress.

Higher grade of concrete that consists of higher bearing strength is required to the pretension concrete which will minimised the creep and shrinkage in the concrete. The most suitable grade would be M30-M45. The concrete that is being used at the construction site are added with admixture that gives the concrete water proof function due to its high water table.

Differences between Pre-stressed Concrete and Reinforced Concrete

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Reinforced concrete has reinforcing bars (called rebar) simply embedded in the pour. With pre-stressed concrete, reinforcing rods or cables are stretched (stressed) and then the concrete is poured around them. After the concrete hardens, the tension on the reinforcing members compresses the concrete, making it more resistant to failure where poor soil conditions or severe loads exist.

Pre-stressed construction is usually done in-plant because of the equipment involved, and the completed assembly shipped to the site for installation.

A similar method, called post-tension, is usually done on site, and involves the tensioning of reinforcing cables after the slab is poured, using a special hydraulic jack.

Advantages of Pre-stressed Concrete

All dead-loads are being counteracted Better corrosion resistance Better shear resistance Good for water tanks and nuclear plant Need less materials Reduce the amount of cracks in the concrete Smaller and lighter structure Take full advantages of high strength concrete and high strength steel Use the entire section to resist the load Very effectively for deflection control Provides lighter and slender members compared to the reinforced concrete. Free from tensile stresses under the working loads which makes it efficient, Provides better resistance against shear force as a result of compressive stresses

counteracting

Disadvantages of Pre-stressed Concrete

Harder to re-cycle Less resistance to fire More complex technically More expensive Need higher quality materials

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Dsignation

M5 1:05:01 5 Lean MixM7.5 1:04:08 7.5M10 1:03:06 10 Ordinary ConcreteM15 1:02:04 15M20 1 : 1 1/2 : 3 20M25 1:01:02 25 Standard ConcreteM30

Designed

30M35 35M40 40M45 45M50 50M55 55M60 60 High Strength Concrete

Mix Proportion

Characteristic Compressive Strength

in N/mm2

Group (as per IS : 567 - 2000)

Group Standard Concrete High strength concrete

M M M M M M M M M M M M M M

10 15 20 25 30 35 40 45 50 55 60 65 70 75

10 25 20 25 30 35 40 45 50 55 60 65 70 75

Ordinary concrete

Grade designation

Specified characteristic strenth at 28

days, MPa

Type of Cement

The strength of concrete is affected by the type of cement used. The higher the strength of cement, the lesser the cement content in concrete. Thus using Grade 45 and 55 provides an advantage of saving cement consumption around 15% and 25% respectively compared to Grade 35 of cement.

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6.0 Conclusion / Learning Outcome

After the meaningful construction site visit done by us on 26 June, there are countless of valuable information of knowledge gained by me after the visit. Besides, I had the opportunity to learn something that I couldn’t learn from the lectures and textbook. I have better understanding about how a construction site works now after the visit.

I had seen and explored various materials and tools used during the construction period. This is an eye opener for me as I have never had the chance to see it with my own eyes. Besides, I was taught by the site contractor about the various professional construction technique used and its application.

Most importantly, I had the chance to witness how much they emphasize on safeties in the construction site. They demand every worker to have their proper safety equipment on when a construction is going on. Even we, the visitors have to wear safety helmet just like other worker to guarantee our safety during our visit since there might be bricks or rocks that might fall from high ground and might hit our head. Moreover, safety signboard were seen everywhere to always remind their worker to emphasize on their own safety.

Moreover, I can see that cooperation between workers is very important through this visit. Every worker at the construction site is cooperating with each other in order to accomplish the task given. This shows that cooperation is very vital in doing something important.

Besides, construction site manager also plays a very important role. As I can see during the visit, the construction site was well planned. There was a site to throw all the domestic waste, and all the materials or tools were kept safe and sound to ensure their stability and secureness when it is being used in the future. Through this site visit, I was able to know further more about the process of different building elements like the installation of a pile, column, formwork, reinforcement and so on.

This site visit really helps us to visualise better in whereabouts of the columns, pile caps, reinforcement bars that we normally seen on a drawing plan. The site visit was very interesting and insightful.

In conclusion, this visit has greatly enhanced my knowledge about construction site. I am very grateful to have a chance to visit there as I have gained a lot of knowledge. I wish that I could have more chances like this in the future as in really benefit me a lot.

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7.0 Photos

Figure 1 : Entrance of Site

Figure 2 : Reinforcement Bars and BRC

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Figure 3 : Formwork & Reinforcement Bars of Column

Figure 4 : High tensile steel bar with 30mm diameter 132 main bars and reduces when height of column increases

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Figure 5 : Grade 35 Pre-stressed concrete in beam

Figure 6 : Used in holding firm the formwork

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Figure 7 : Steels are being placed around the formwork to strengthen it

Figure 8 : Temporary Works – Scaffolding

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Figure 9 : For the installation of tower crane

Figure 10 : Bar Bending Machine that is capable to bend up to 40mm diameter steel bar

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Figure 11 : Bar Cutting Machine

Figure 12 : Making the concrete cover

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Figure 13 : Pilecap of a villa

Figure 14 : Pilecap of the condominium

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Figure 15 : 35mm diameter Reinforcement bar of a pilecap

Figure 16: Biggest pilecap on site with 540m3

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Figure 17 : 1200 diameter Bore Pile Grade 30 concrete with caisson around

Figure 18 : Casing for Bored Pile

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Figure 19 : Extra Bored Pile that was hacked off

Figure 20 : Machine that is used to hack off the extra bored pile

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Figure 21 : Equipment with special gas to cut off the extra reinforcement bar in bore pile after hacking off the extra concrete

Figure 22 : Temporary work – wooden cabin

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Figure 23 : Temporary Container Office

Figure 24 : Group photos for group 1

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assignment of site report

Education

construction site visit

site surveying

site contractor

site clearance

construction team

construction process

construction of basement

construction of bored