CT - BASEMENT

FACULTY OF ARCHITECTURE, PLANNING, AND SURVEYING
UNIVERSITI TEKNOLOGI MARA (UiTM)
SHAH ALAM, SELANGOR

BQS552
CONSTRUCTION TECHNOLOGY IV

CASE STUDY: BASEMENT

PREPARED BY: STUDENT ID

STUDENT’S NAME 2020455448
2020847342
NUR RABIHA BINTI AMRAN 2020844468
MARYAM BINTI AGUS SALIM 2020476962
SYAZA SYAZLIN BINTI JAMHURI 2020477062
NURAISYAH BINTI JOHARI
NUR FADHLIN HANA BINTI MOHD HAZRUL

GROUP: AP2244A

PREPARED FOR:
DR ANIS ROSNIZA NIZAM BAKAR

DATE OF SUBMISSION:
22 JUNE 2022

TABLE OF CONTENTS

INTRODUCTION 2

TASK 1 3
1.0 LITERATURE REVIEW 4
1.1 TYPES OF BASEMENT CONSTRUCTION METHOD 4
1.2 TYPICAL CONSTRUCTION PROCESS OF BASEMENT 10
1.3 PLANT AND MACHINERY USED 14
1.4 MATERIAL USED 19
1.5 STANDARD SAFETY PROCEDURE 22

TASK 2 25
2.0 CASE STUDY I: MERDEKA PNB 118 26
2.1 PROJECT BACKGROUND 26
2.2 PARTIES INVOLVED 30
2.3 TYPES/METHOD OF CONSTRUCTION 31
2.4 CONSTRUCTION PROCESS 32
2.5 SAFETY PROCEDURES 34
2.6 PROBLEMS OCCURRED 35
2.7 STEPS AND SOLUTION TO SOLVE 36
3.0 CASE STUDY II: ILHAM BARU TOWER (IB TOWER), KLCC IN KUALA LUMPUR 37
3.1 PROJECT BACKGROUND 37
3.2 PARTIES INVOLVED 40
3.3 TYPES/METHOD OF CONSTRUCTION 41
3.4 CONSTRUCTION PROCESS 42
3.5 SAFETY PROCEDURE 43
3.6 PROBLEMS OCCURED 45
3.7 STEPS AND SOLUTIONS TO SOLVE 46
4.0 COMPARATIVE STUDIES 47
4.1 SIMILARITIES 47
4.2 DIFFERENCES 48

CONCLUSION 51

REFERENCES 52

1

INTRODUCTION

In this report, we chose the Basement as our topic. So, what is the basement?
Basement can be defined as a building with one or more storeys that are totally or partially
below the ground floor. Basement is also known as cellar which also gives the same meaning.
It’s usually utilised as a building’s utility space, with equipment like the furnace, water heater,
breaker panel or fuse box, vehicle park, and air-conditioning system, as well as amenities like
the electrical system and cable television distribution point.

However, not all buildings have a basement. Basements can be found in a wide range of
homes, and they can be a bit of a mystery if you don’t know much about the home’s past. Every
sort of basement, from a crawl space basement to a cellar, has a long and illustrious history.
But, basements are classified as daylight basements, look-out basements, cellars, and crawl
space in the building industry.

A variety of factors that must be examined before construction begins will affect the
method used to construct the basement. The important factors that need to be looked at are the
dead and live load of the superstructure, the wind loads which applied for higher structure, and
the last one is water pressure during and after construction of the basement. Meanwhile, the
size of the site, the volume of work, the shape and typographical characteristics of the site,the
site’s neighbourhood, and the geotechnical conditions all influence the method of the basement
construction chosen.

The Occupational Safety and Health Administration (OSHA) must establish specific
guidelines to minimise the possibility of mishaps or unpleasant events occurring on job sites due
to the high risk of construction, particularly during this pandemic season. Therefore, in this
report, we will explain further in details on standard safety procedures later. Before that, we will
explain the types of basements and the typical construction process of the basement. Not to
forget, the material, and plant and machinery that was used in the basement construction.

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TASK 1
BASEMENT LITERATURE REVIEW

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1.0 LITERATURE REVIEW

1.1 TYPES OF BASEMENT CONSTRUCTION METHOD

Every structure rests on a foundation, which is built into the earth and supports the
structure that sits on top of it. The support system for an entire structure is formed by foundation
walls, which are typically made of concrete, brick, or cinder blocks. When a building has a
basement, it is located at the foundation's lowest point. In detail, a basement in a simple word is
an area of the house that has been built underground. Nowadays, basements have been
transformed into entertainment areas for storage purposes. People will store water, carpark,
working purpose and even food down there as the basement is built in the ground so it is damp
and humid there. Typically, there are several types of basement construction methods followed
by the suitability of the ground needed.

1.1.1 Top-Down Construction

This construction method is commonly used in urban areas to build high-rise buildings. A
simple word determining the top-down construction is that the basement floors or substructure
of the building are built in such a way that after the completion of the ground floor (Iqbal, 2018).
These types of construction methods are currently used for two types of urban structures which
are tall buildings with deep basements and underground structures such as parking garages,
underpasses, and subway stations. The basement floor is constructed floor by floor from the top
to the bottom of the basement along with deep excavations that are usually called a reverse
method. The method has been used in deep excavation operations where tieback or anchor
installations were not possible and soil movements were limited, such as for the tunnel
construction.

It begins with the construction of load-bearing foundation walls that support the whole
structure and the installation of a concrete ground floor on top of those walls followed by a
retaining wall installation. Next, the use of the permanent internal structure acts as a temporary
propping to the retaining wall in a top-down sequence, which is defined as top-down (Rijeka,
2022). The higher-level slabs are cast first, followed by the lower-level slabs, to serve as
horizontal frames for wall support as the excavation progresses. After that, the basement
columns, which are steel beams, are built before any excavation and rest on load-bearing
elements. Concrete piles or diaphragm wall panels are recently used as load-bearing elements.

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In the meantime, this method is more expensive than open-cut excavation, but it is faster
because it allows the upper floors of a building to be built while the basement is being
excavated. The early restoration of the superstructure is possible even before the building is
completed, and the structures above ground can be completed concurrently with the structures
below ground. This significantly reduces construction time. In benefits, this type of method helps
in lowering a danger in ground movement, providing a safer construction environment as it
requires a less width for the site area and a reduction in the impact of adverse weather. As a
result, due to the location beneath is dark and dusty, this strategy necessitates a large budget,
restricts material handling access to the site, and necessitates a lot of lighting and ventilation.
This technology is suitable for large, complicated basements as well as soil nailing.

Figure 1: Top-Down Construction

1.1.2 Cut and Cover Construction
The cut and cover method is a traditional tunnelling technique in highway engineering

that entails opening up the ground surface and excavating to the required depth. A
cut-and-cover construction has also been used for many years to build underground
transportation systems in congested areas where open excavation techniques would cause
significant disruption to traffic. The method's main concept is full-length or sequential excavation
along the road segment, followed by tunnel bore construction (Mouratidis, 2008). Backfilling
requires a well-monitored construction process that is adequately defined in terms of equipment
and quality control after drainage and waterproofing measures (Mouratidis, 2008).

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Under normal building engineering conditions, it entails excavating an open cut using
essentially the same technical methods as traditional excavation and erecting a single or twin
tunnel lining (Mouratidis, 2008). Construction of temporary walls to support the excavation's
sides, a bracing system, ground water control, and, if necessary, underpinning of surrounding
structures are all part of this method. Most of the time, this is done in a congested area such as
an urban area. Conversely, this method is also applicable in a rural area where it is mostly the
landslide risk that leads to the solution of the “cover and cut” technique. The method's main
requirements for application are the dominance of soft or weak ground conditions and/or low
overburden.

The method's fundamental concept consists of a first stage of constructing the "cover,"
an earth-retaining concrete shell, followed by a second stage, the "cutting" operation, which
represents the main excavating activities beneath the previously constructed "cover." Concrete
vaults provide safe cover for excavating activities beneath, establishing these retaining effects in
road tunnel engineering. The state of the groundwater determines whether a permanent or
temporary retaining wall is used. The tunnel will be concretized once the foundation level is
reached, followed by waterproofing and backfilling. As a result, this cut and cover procedure
may have an impact on the surrounding congested space, and the cost may rapidly increase as
the depth is increased. The cut and cover method has the advantage of being very cost effective
in shallow depth tunnel construction. This method works well when dealing with sloppy or weak
materials.

Figure 2: Cut and Cover Construction in Underground

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1.1.3 Open Cut Construction

The Open Cut Method is a very old method of basement construction. This open cut
method has recently been used in open space areas with no obstructions and no nearby
building or structure. When working with dense, sturdy soil, the open cut method can be the
most cost effective of all basement construction methods rather than other methods. However, it
is uneconomical to dig deeper than 6m due to the large excavation work and the need for a
retaining wall. In benefits, this method works with almost any soil including clay. The open cut
method begins with basement excavation and progresses upward from there. When a trench is
extremely deep and expensive backfill materials are necessary, a vertical cut at the toe of the
slope supported by shoring may be an effective solution to the problem.

In addition, there are two types of open cut method which is a slope open cut excavation
and open cut cantilevered excavation. A sloped open cut excavation is the most cost-effective
and time-efficient excavation method. From sloped open cuts that do not require retaining walls
to cantilevered open cuts that do, open cut excavation provides architects, builders, and
homeowners with a variety of options. The open cut slope method is ideal for one- and two-story
buildings with shallow basements as it uses basic physics to protect your home's foundation
from collapsing soil. From earth excavation to performing a basement, the slope's natural
properties eliminate the need for retaining walls that make the open cut slope less expensive.

Besides, before construction begins on an open cut cantilevered excavation, soil must
be excavated. However, unlike the slope method, the cantilevered method necessitates the use
of retaining walls. These walls enable deeper basements. They also keep groundwater from
flooding construction sites. The disadvantage is that retaining walls increase the overall
construction time and cost. Due to the use of retaining walls, the open cut cantilevered method
works well for taller buildings with deeper foundations and multi-level basements.

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The slope angle and ground area will be distinguished based on the results of its design,
analysis, and evaluation. As a result of the open space location, this technology can be used in
virtually any soil condition and allows for continuous excavation, laying, and backfilling activities.
This technology has the benefits of reducing construction time for shallow basements, being
cost-effective, allowing for quick access, and requiring no additional support operations or
equipment. In-depth, it comes with several benefits that make most construction fields use this
type of method which is reasonably priced as basement excavation is never cheap, but the
open cut slope method necessitates the most basic structural engineering and eliminates the
need for sometimes costly retaining walls. Next, potentially adaptable due to the open cut
slopes, only work on shallow basements in low-rise buildings. Cantilevered open cuts, on the
other hand, are extremely versatile. This method can be combined with bracing or anchors to
create large, ambitious buildings with multi-level basements.

Figure 3: Open Cut Construction

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1.1.4 Composite Construction
The main difference is that pre-founded columns are only built around the perimeter

rather than over and across the suggested floor plan area. The band of supported slabs above
these pre-founded columns in the proposed floor plan will provide natural daylight and increased
ventilation through the centre or core areas. This method was developed to address the
drawbacks of working in a dusty and dark environment. This will make it easier to excavate,
haul, load, and cart away excavated items, as well as bring in new materials. As a result, fresh
resources will be brought in more conveniently because of the convenient access. This is
essentially a hybrid of top-down and bottom-up approaches.

Figure 4: Composite Basement Construction

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1.2 TYPICAL CONSTRUCTION PROCESS OF BASEMENT

1.2.1 Open Cut Method

The open cut technique is the most common basement building method. The excavation
is completed to the necessary foundation level. The sides of the excavation are sloping to
ensure the stability of the cut slope. The maximum slope which is the highest angle that the soil
would not slide or collapse without support that changes with soil type. For example, 45° for wet
sand, 34° for dry sand or gravel, and 25° for clay. This will need extra room around the
excavation, which is not always accessible on development projects. When the foundation's
starting level is reached, the basement will be built upward as shown in Figure 5. The remaining
excavated sections between the side slopes and the basement will be backfilled after the
basement is completed. Before backfilling, the basement wall is normally waterproofed. It
should be noted that on wet days, the sloping sides must be covered from water infiltration. The
figure shows that the sloping sides need a large amount of building space, which is impossible
in a highly populated urban area. Ground movement around the excavation may potentially be
an issue for this kind of construction.

Figure 5: Open Cut Method

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1.2.2 Cut and Cover Method

This basement building technique is appropriate for limited areas where ground
movement around the site must be controlled. A construction site that is frequently relatively
close to other nearby buildings and roadways. Significant soil excavation and groundwater
drawdown may have serious effects for ground movement and, of course, settling of
surrounding buildings. The cut and cover method needs the excavation to be supported by
braced retaining walls.

The building sequence may be summarised as follows, before excavation, retaining
walls (sheet pile walls or diaphragm walls) are built. The bracing frame's posts have been fitted.
Second, excavation continues near the ground surface. At the proper level, the first set of struts
and bracing will be erected. Third, as the excavation continues lower, more struts and bracing
will be placed to hold the retaining wall. Then, construction of the basement starts after the
foundation's forming level is achieved. After that, depending on the style of retaining wall, it may
serve as a permanent basement wall (for diaphragm wall construction). If the retaining wall is a
sheet pile wall system, building of the basement wall will begin after the foundation. The sheet
pile wall is then employed as the formwork surface for the basement wall construction. As
basement work progresses, the strut and bracing will be removed. If a diaphragm wall is used
as the basement wall, the basement beam and slab will be joined to the wall at sites where
starting bars have been put. The beam and slab will then offer the necessary lateral support to
the wall against the lateral pressure from the surrounding earth.

Figure 6: Cut and Cover Method

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1.2.3 Top Down Construction

Bottom-up construction may not be cost-effective if the building project must be finished
as quickly as feasible (early return on capital, rental revenue, and lower market risk). To address
this issue, for buildings with basements, the top-down construction approach can shorten
project construction time. The core concept is that the excavation, basement, and
superstructure may all be built at the same time. The top-down method's building sequence may
be summarised as follows:

1) Construct the diaphragm wall that will serve as the permanent basement wall for the
substructure. For the connections to the beams and slabs, starter bars are connected
(boxed out) to the diaphragm wall.

2) Bored holes are dug on-site, and pile foundations are built to support interior columns
(usually steel stanchions) later on. These columns will serve as the foundation's primary
structural elements. It should be noted that the columns are often "punched" through the
concrete (before it is set) to the correct level. Beam and slab connections will be joined
to the columns in the form of steel couplers.

3) Soil is then backfilled into the drilled holes to provide lateral support to steel columns.
4) An upper section of the stanchions is seen from the ground. This section of the

stanchion will allow the superstructure and ground level slab to be built.
5) After the ground floor slab is cast, excavation for the first level of the basement will begin

alongside the building of the superstructure.
6) When the first basement level is achieved, beams and slabs will be built which are

connected to the starter bars and the steel couplers in the exposed diaphragm wall and
the steel stanchions, respectively.
7) The basement floor beam and slab system will provide lateral support to the diaphragm
wall.
8) Temporary gaps in the slabs at ground and basement levels are frequently constructed
to allow for additional excavation below. These temporary openings give digging
machines access and the removal of excavated soils.
9) Ramps may also be erected to allow dump trucks to enter the basement in order to
move excavated soils away from the building site faster.

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10) The excavation and construction of the beams and slabs will continue for each
basement level until the basement slab formation level is achieved. The foundation slab
or ground beams will thereafter be built.

Figure 7: Top Down Construction

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1.3 PLANT AND MACHINERY USED

1.3.1 Excavator

Figure 8: Excavator

Excavators are significant pieces of construction equipment that are commonly
employed. Its primary function is excavation, although it is also used for a variety of other tasks
such as pulling weights, destroying, digging rivers, and chopping down trees. Long sleeves and
cabinets are found on excavators. A bucket with a capacity of roughly 50 cubic metres of dirt
filling and long-arm digs is provided at the end of the bucket, and a cabinet is given for the
machine operator. This cabin's overall design can be turned up to 360 degrees, making it easier
to operate. The goal of underground excavation is to dig a deep excavation with a crane with a
maximum excavation depth range. It also has the ability to quickly descend and ascend.

1.3.2 Crane

Figure 7: Crane

During deep excavation, a crane can be utilised to carry a large cargo to a deeper section of the
basement. Because mobile cranes are less expensive to lease and acquire than tower cranes,
they are commonly used for excavation.

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1.3.3 Backhoe

Figure 8: Backhoe
With a front loader and a smaller scoop in the back, the backhoe resembles a tractor.
These machines are tiny and agile, making them perfect for confined spaces such as basement
construction. They're also great for digging clean service trenches for utilities like power, water,
and drainage. They're also useful for digging clean utility trenches for things like electricity,
water, and drainage. Backhoes with loaders may move large goods such as cement bags,
reinforcement, and other comparable products.

1.3.4 Lorry

Figure 9: Lorry
A lorry is required for every building construction, notably basement development. This is
because the basement will generate a significant volume of material. As a result, the excavation
material will be hauled by lorry away from the construction site. Lorries are available in a range
of sizes, such as 5MT, 10MT, and others.

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1.3.5 Pump

Figure 10: Pump
A dewatering device was employed to pump water out of the excavation due to the high
water level at the site. The dewatering system is one of the most important construction
machinery since every excavation method for a basement requires pumping machinery to pump
water. Sump pumps, well point systems, horizontal groundwater control, and deep and shallow
drilled wells are all examples of dewatering systems.

1.3.6 Loaders

Figure 11: Loaders
At construction sites, loaders are used to load materials into landfills, trucks, and other
vehicles. Excavated soil, demolition waste, raw materials, and other items may be used. In front
of the loader, there is a huge bucket with a shorter moving arm. Tracked or wheeled loaders are
available. On-site, wheeled loaders are common, but track or crawl loaders are employed in
areas that are inaccessible by wheeled vehicles. Loaders can aid in the construction process by
speeding it up.

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1.3.7 Hydraulic Vibro Hammer

Figure 12: Hydraulic Vibro Hammer
In rare circumstances, piles may be required to support underground construction due to
poor soil conditions. With a hammer attachment, it is frequently used to break through barriers
such as huge rocks. As a result, piles such as secant piles and other types of piles will be
installed using the Hydraulic Vibro Hammer.
1.3.8 Cement Mixer Truck

Figure 13: Cement Mixer Truck
Ready-mixed concrete is often utilised for concrete procedures because basement
buildings need significant amounts of concrete in a short period of time. As a result,
ready-mixed concrete is the most suitable material for basements. Cement Mixer Trucks have
the ability to mix massive quantities of concrete. It's also capable of transporting concrete both
off and on-site.

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1.3.9 Concrete Vibrator

Figure 14: Concrete Vibrator
Concrete vibrators are machines that help compact concrete that has been laid out on a
construction site. Concrete compaction will make it easier to level the concrete in the basement
and will speed up the process. Concrete vibrators include surface vibrators, needle vibrators,
concrete vibrating tables, and external vibrators or shutters. The most common vibrators used in
construction are needle vibrators, however different types are required in particular scenarios.

1.3.10 Dump Truck

Figure 15: Dump Truck
Dumper trucks are generally used to transport building materials to and from
construction sites. It's the safest way to get loose materials off the site quickly, and it's especially
vital in the early stages of projects when soil is being prepared for work to start, as well as
fertilising soil for basement excavation operations.

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1.4 MATERIAL USED
1.4.1 Poured Concrete

Figure 16: Poured Concrete
The most frequent and favoured type of building for most individuals is poured concrete
basements. Pouring a footing for the basement foundation is the first step in the building of this
sort of basement. The form is then used to hold the poured concrete wall in place while it dries.
Basement walls made of poured concrete are often stronger than those made of other
materials. The form is used to keep the wall in place as it dries. As a result, the basement walls
are robust and rarely cause difficulties. When water leaks do occur in poured concrete walls,
they usually start at the joints where the walls meet the floor. Cracks in the walls are also
possible, which might allow small amounts of water to flow into the basement over time.
1.4.2 Concrete Block

Figure 17: Concrete Block
Concrete or stone blocks are the most cost-effective alternative for basement building.
The cinder block walls can be constructed in a fraction of the time it takes to construct a poured

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concrete wall. Steel rebars are frequently employed to reinforce the structural integrity of these
walls. Water leakage is more likely to occur in concrete block walls. Water can infiltrate through
the mortar that connects individual blocks, in addition to potential leaks along floor and wall
connections. The cinder block's hollow design allows it to retain water for a long time after it
enters, even after the soil surrounding it has dried.

1.4.3 Precast Panel

Figure 18: Precast Panel
Many contemporary residential projects will use precast foundation walls to save money
and time on the construction site. These walls are built elsewhere and then brought to the
construction site when they're ready to go. Although precast panel walls are remarkably sturdy,
they are less frequent than poured concrete construction. Precast panels are made from a
high-strength, low-water concrete mix, making them more water resistant in the long run. Water
damage, on the other hand, tends to emerge along the connection between the walls and the
floor.

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1.4.4 Stone or Clay Tile Walls

Figure 19: Stone or Clay Tile Walls
When buying an older or historic home, the basement foundation may be made of stone
or clay tile. In previous decades, such walls were rather prevalent, and they were typically used
when other materials were not easily accessible. They can be extremely powerful, but they also
tend to be more primitive in character. The most serious problem associated with stone and clay
tile basement foundations is that groundwater can easily seep through and into the basement.
This is especially true with stone walls with numerous gaps and fissures. To solve this problem,
an inside perimeter drain system is normally required.

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1.5 STANDARD SAFETY PROCEDURE

Basement building has a significant construction risk. This work is done in relatively
limited areas, close to the general public going about their daily lives. All basement construction
projects should have suitable health and safety management in place, including provisions for
access to competent health and safety advice on general and construction problems, in order
for this work to be completed safely.

1.5.1 Safety Hazards
i. Access to work areas
Workers, plants, and excavated material must always have safe entrances and
exits. Whenever possible, personnel access should be through temporary staircases
rather than ladders. Also, multiple points of entry and exit should be constructed
wherever possible. At all times, there must be safe access to all active working areas.
Safe access must be adequate to allow a casualty to move around.
ii. Scaffolding safety
Scaffolding towers must be appropriate for the work, and they must be erected
and dismantled by persons who have been qualified and are capable of doing so.
Furthermore, users must be aware of potential hazards and the necessary safety
procedures. Also, a reputable scaffolding business with competent operators should
install the tube and fitting scaffold. The scaffold should be inspected and maintained on a
regular basis once it has been installed.
iii. Lighting
Poor site lighting raises the risk of harm in a variety of other ways. At all times, all
work areas, access, and exit paths, and passageways must be properly and safely
illuminated. To cover for a malfunction in the main works, lighting, torches or automatic
backup lighting should be provided. Wherever temporary lighting is required, battery
backup emergency lighting should be included, especially on the emergency exit paths.

1.5.2 Health Hazards
i. Carbon monoxide and other noxious gases
Leaking underground gas mains are a danger. A mains gas leak can quickly
create a hazardous environment. The key mitigations that can be implemented are
adequate ventilation and properly maintained plants and equipment. Additionally, gas
bottles should be stored outside and valves should be closed at the end of each shift,

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gas detectors and alarms should be installed, and generators should only be used
outside and totally in the open air.
ii. Damage to eyes
On-site activities such as breaking concrete, grinding, and cutting wood all provide a
considerable risk of eye injury. While the risk of injury from a single labour activity is
minimal, damage to an eye caused by even a little hit can result in lifelong blindness. For
any industrial activity that involves the chance of material being transported at a high
rate into the eye, proper eye protection should be worn at all times.
iii. Noise

Long-term exposure to excessive noise levels reduces hearing levels and finally
leads to permanent deafness. As a general rule, a noise level that needs raising one's
voice to be heard is loud enough to induce hearing impairment. Wherever possible, the
volume and duration of noisy operations should be reduced and the noise sources
should be positioned away from inhabited work areas, and in particular, away from
welfare services. Everyone in an environment where there is noise at a level that could
cause hearing damage should wear ear protection.

1.5.3 Health and Safety of Others
i. Site security and access restrictions
Unauthorised persons must not be allowed access to the project site, and
reasonable measures must be taken to prevent this. Access should only be granted to
those who have been given specific permission. Members of the public, particularly
children, must not be allowed to enter the site at any time. Workers transporting
materials onto the site leave the main site door open and unsupervised, which is a
regular mistake in basement construction works. This cannot be accepted.
ii. Warning signs
Warning signs should be prominently displayed and placed where they are most
likely to be noticed by visitors.
iii. Work access
All places of work must have safe entry and exit built and maintained. When
working in a restricted area, more caution should be exercised, and all reasonable
attempts should be made to ensure numerous exit routes. All emergency service vehicle
access points must be open at all times. Separate pedestrian and vehicular entrances
should be specified for bigger sites, where practical. Vehicle access to the site should

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avoid potentially dangerous situations, such as being too close to overhead power lines
or obstructing other road users. Dirt, muck, and dust shall not be moved off of the
construction site onto public routes.
1.5.4 Emergency Planning and Procedures
i. Serious or imminent danger

In the event of major and urgent danger, procedures must be in place. During site
induction, these processes must be conveyed to all employees. The arrangements
should also cover the general public, particularly if occupied structures are at risk of
structural failure or fire spread.
ii. First aid

A first aid risk assessment must be carried out to ensure that adequate and
appropriate first aid equipment, facilities, and qualified staff are available so that persons
working on-site may receive immediate assistance if they are hurt or become sick while
on the job. Each project work site must include a supplied first-aid box with eye wash
and wound dressings, as well as a first-aid trained operative. They should also have
information about first-aid arrangements and contact information for individuals working
on-site, as well as a map giving routes to the closest emergency care department.

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TASK 2
CASE STUDY
CASE STUDY I:
MERDEKA PNB 118
CASE STUDY II:
ILHAM BARU TOWER (IB TOWER), KLCC IN KUALA LUMPUR

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2.0 CASE STUDY I: MERDEKA PNB 118

2.1 PROJECT BACKGROUND

Merdeka PNB 118, or just Merdeka 118, is the tower's official name. Merdeka signifies
"Independence Day" in Malaysia, and the tower's name honours Malaysia's independence. It
will also be constructed on the site of the former Merdeka Park. The tower was previously
known as KL 118 since it will be located in Kuala Lumpur and have 118 stories. Other names for
the skyscraper include Menara Warisan Merdeka, which means Heritage of Independence in
English, and Permodalan Nasional Berhad, PNB Headquarters because it will be the new
headquarters for the PNB Group.

Merdeka118 was designed by RSP Architects Sdn Bhd in collaboration with Fender
Katsalidis, a Melbourne-based architectural practice whose most well-known work is the Eureka
Tower, Melbourne's tallest building. The Merdeka PNB 118 will be crowned by a 150-metre-long
spire. The raised right hand of Tunku Abdul Rahman who is recognized as Malaysia's founding
father seen at the Merdeka Proclamation, symbolising the country's independence, inspired the
tower's off-centre spire. The Merdeka PNB 118 will have a total floor space of 292,000 square
metres (3143,062 square feet). The cost of constructing this tower is expected to be RM5 billion,
or about US $1.5 billion.

Merdeka PNB 118's architectural height is 678.9 metres (2227 feet), measured from the
ground to the spire's peak. This height was only revealed on November 30, 2021, when the
tower reached its full height. The top of the crown is projected to be around 570 metres above
mean sea level, and the altitude of the tower's location is 55 metres, meaning the tower is 515
metres tall without the spire. The roof is 500 metres above ground level, or 555 metres above
mean sea level. At 485 metres above sea level, the highest occupied floor is located. If the
tower is completed on schedule in 2022, it will overtake the iconic Petronas Towers and The
Exchange 106 to become Malaysia's tallest structure and the world's second tallest building.

The podium floors of the KL 118 Tower would be occupied by retail stores or a shopping
mall, while the top 80 floors of the building would be used as office space, with 60 of these 80
floors set aside to serve as the headquarters of Permodalan Nasional Berhad (PNB), the
building's owner and developer, as well as the company after which the tower is named. There
will be 12 stories of hotel rooms and 5 stories of hotel suites on the upper floors. A restaurant
will be on the 113th floor, and a multi-story observation deck will be on the 114th to 117th floors,

26

making it one of the world's highest observation decks. A VIP lounge will be located on the top
floor (118th floor). Up to 5,000 cars will be able to park in the basement parking area.

Figure 20: The Raised Right Hand of Tunku Abdul Rahman inspired the Design of Merdeka 118

Figure 21: The Development of Merdeka 118
27

ITEM DESCRIPTION
PROJECT NAME
OWNER OF PROJECT MERDEKA PNB 118
NAME AND ADDRESS OF ARCHITECTURE
CONTRACTOR NAME PERMODALAN NASIONAL BERHAD (PNB)

DATE OF COMMENCEMENT RSP ARCHITECTS SDN BHD
DATE OF COMPLETION
PINTARAS GEOTECHNICS SDN BHD
UEM GROUP
SOUTH KOREA’S SAMSUNG C&T

2014

EXPECTED TO BE COMPLETED IN 2022

Figure 22: The Structural System of Merdeka 118

28

Figure 23: Location of Merdeka 118
29

2.2 PARTIES INVOLVED Permodalan Nasional Berhad (PNB)
Client

Design Architect Fender Katsalidis

Local Collaborating Architect RSP Architects Sdn Bhd

Main Contractor: Piling and Substructure Pintaras Geotechnics Sdn Bhd

Main Contractor (Joint Venture): UEM Group
Superstructure South Korea’s Samsung C&T

M&E Engineer KONE Corporation

30

2.3 TYPES/METHOD OF CONSTRUCTION

Due to the building's height restriction and other ground surface constraints, people are
beginning to consider using underground space and developing the basement for car parking or
public transit stations. Traditional top-down and bottom-up methodologies can be used. The
top-down approach is typically used for two types of urban constructions: tall buildings with deep
basements and underground structures like parking garages. The top-down approach was used
for this construction because it allows the superstructure to be erected along with the
substructure. Aside from that, it has a very significant vertical load capacity of the wall and
internal column to support the growing superstructure load during the building sequence,
although access to the substructure works through the superstructure works might be a critical
task on small, confined sites. Basement dewatering is also allowed in this situation. Dewatering
is the removal of water from solid materials. Dewatering is usually done using a pump, however,
alternatives such as dry beds and solar drying methods have been researched. Dewatering is
also extensively used in sludge treatment and large industrial activities. Water should never
enter the basement if the waterproofing system is functioning properly, but should be absorbed
as it passes through the drainage system from the groundwater.

Figure 24: Basement construction

31

2.4 CONSTRUCTION PROCESS
Top-down construction has been employed for several large-scale projects where time is

of the highest importance, saving significant amounts of overall construction time. The
installation of retaining walls is the first step in the building process, followed by the installation
of load-bearing components that will support the future superstructure. The building process
begins with the erection of retaining walls around the perimeter of the structure. Diaphragm
walls are most commonly used in this manner. During construction, the retaining wall doubles as
a basement wall. Columns are inserted after the retaining walls are installed to support the
structural load during the excavation and building phases. When the temporary columns are in
place, the slab for the first floor is erected above the site ground.

Following the construction of the first floor slab, the excavation of the first basement level
beneath the slab begins. Because the excavation is done beneath the slab, noise and dust are
kept to a minimum. The placement of the slab completes the first basement level's construction.
Because the first upper level development was finished continuously, the second basement
level is being built in the same manner. The process is continued until the required basement
level is reached. Once the excavation of the designated basement level is completed, the final
footing which is mat foundation is built. The building of the taller structure will continue until it
reaches the appropriate floor level.

32

Figure 25 shows a top-down building process schematic.
iii. Retaining wall construction
iv. Column construction
v. First basement level excavation
vi. Building the first basement level slab
vii. Synchronous construction
viii. Base footing construction

Figure 25: Top Down Construction Process

33

2.5 SAFETY PROCEDURES

Underground basement construction is a specialised and high-risk endeavour that may
disturb the structural integrity of existing structures. It is the contractor's responsibility to ensure
that construction work is planned and completed in a safe and efficient manner. This includes
identifying temporary works, such as trench supports, that are required to keep any excavation
or existing structures intact. The following safety procedures are recommended to keep
everyone on the construction site safe.

Firstly, the collapse of existing buildings shall be taken in safety guidelines as the case
study chosen is surrounded by the existing buildings. Basement construction near existing
structures always poses the risk of complete or partial building collapse. The hazard is
frequently associated with excavation collapse. The risk assessment must consider the
building's existing load paths, how they will be affected by the temporary works and condition,
and whether any parts of the existing building will be required to support the additional load.
Secondly, an inspection of the tools and electrical equipment. All tools and equipment will be
visually inspected on a regular basis, and those that are found to be faulty or damaged will be
removed from service. Subcontractors will not be permitted to bring broken or malfunctioning
tools onto the job site, and the site foreman will be in charge of ensuring that all tools and
equipment are fit for purpose.

In addition, all construction workers need to wear Personal Protective Equipment (PPE).
Before arriving at the site, all workers must put on their PPE. They must wear appropriate
protective equipment to protect themselves in the event of a workplace accident (PPE). For
example, high visibility clothing will help us be seen, while safety boots will provide traction and
protection for our feet. Personal Protective Equipment (PPE) such as a hard hat, safety boots,
and a high-visibility vest are considered to be the basic requirements before the job is carried
out. In depth, the retaining Wall Selection by The Civil and Structural Engineer needs to be
taken in order to avoid any circumstance. For this project, a permanent retaining wall was built
to protect the soil and prevent ground movements caused by excavation. The tower's
diaphragm wall thickness of 800mm was chosen to improve basement construction. However,
the excavation plan should be prepared in advance as there may be unforeseen occurrences
such as the overload at the retained side of the wall being larger than estimated.

34

2.6 PROBLEMS OCCURRED
During the construction of Merdeka 118, there were a few problems that happened. This

problem has caused the project to become delayed. The major problem in this project is the
project needs to be stopped due to the Movement Control Order (MCO). Other industries also
have been affected due to MCO, not only in Malaysia but all around the world also faced the
COVID-19 pandemic. Therefore, Merdeka 118 construction site was closed during the first three
phases of the cordon sanitaire. Since the project needs to be closed, the completion time of the
project has been set to a two to three months extension.

Merdeka 118 construction site is located in the middle of Kuala Lumpur city. Other than
the above problem, this project also faced limited space and congested area problems. It is hard
for the transportation that carries materials to get in and out from the construction site as Kuala
Lumpur is known as a bustling area. Therefore, the construction process, which required
transportation, was impeded by heavy inbound traffic during peak hours, especially on
weekdays.

Lastly, noise pollution is a widespread issue that affects practically all construction
projects. The citizens who live close and in the area will be bothered by the noise that some of
the machinery and equipment used such as the hydraulic hammer and excavator, would
produce. The construction site workers may also be at risk of health issues like hearing loss and
hearing impairment due to extended exposure to high noise.

35

2.7 STEPS AND SOLUTION TO SOLVE
It is common that every project will face some problems or issues. Sometimes, we never

expect we will face that problem or issue. But, by depending on the ways how the construction
or project management handles the problem or issues, for sure we will find the solution for every
problem that occurs. As a result, continual efforts have been undertaken by the appropriate
specialist to suggest new and effective solutions to problem-solving.

Government has announced that there is a new Standard Operating Procedures (SOP)
for each industry. Therefore, this can solve the first issues where the project has been delayed
due to the MCO. Those parties that are involved in the construction site should rigorously follow
the SOPs established by the Construction Industry Development Board and the International
Trade and Industry Ministry (CIDB). The rules or SOPs that have been set are that there are
only 50% workers in the construction site and the workers need to be vaccinated.

Next, since there is limited space and congested area at the construction site as the
Merdeka 118 building was built in the middle of Kuala Lumpur city, the transportation works
need to be scheduled. During weekdays, the traffic was really heavy and to avoid it, they
needed to have a schedule so that the transportation did not get stuck in traffic. Meanwhile,
inside the construction site, excavated materials need to be removed off site frequently so that
the area can be used to place the new material.

Wearing protective equipment is the last solution for the noise pollution problem. This is
because the construction site workers may also be at risk of health issues like hearing loss and
hearing impairment due to extended exposure to high noise. Therefore, in order to protect their
hearing, site workers will wear personal protection equipment like earplugs and earmuffs.
Besides that, for the residents that live near the construction site, in order to avoid disturbing the
residents outside of working hours, work involving machinery that makes a lot of noise will only
be scheduled during working hours.

36

3.0 CASE STUDY II: ILHAM BARU TOWER (IB TOWER), KLCC IN KUALA LUMPUR

3.1 PROJECT BACKGROUND

The Ilham Baru Tower known as IB Tower is one of the most beautiful skyscrapers in
Kuala Lumpur also in the world, with its distinctive diamonds geometry, which was inspired by
the necessity for a flexible and column-free region to accommodate a variety of tower functions
and made possible by the tower's innovative and self-reinforcing diagrid structure. It's located on
Jalan Binjai in Kuala Lumpur, Malaysia. In March 2017, the IB Tower construction project was
successfully finished. The building has a total of 58 floors. Foster + Partners designed the
structure, which is 274 metres (899 feet) tall. It is also one of Malaysia's seventh tallest
skyscrapers. A Grade A office suite, a 4-star hotel, an art gallery, a gift shop, and food and
beverage outlets are all part of the 60-story Ilham Tower. This incredible creation is a paradigm
of harmony, fitted to today's business and leisure needs. For a total of 1,000,000 square feet of
gross floor area, there are 33 levels of office suites and 22 levels of serviced apartments
(93,000 square metres). In the back of Tower block, there are four basements and a five-story
platform. Employees and guests to Ilham Tower can park for free. The diaphragm wall
construction of the retaining system has an overall thickness of 600mm. In top-down
construction, the subsurface ring slabs serve as horizontal struts.

The IB Tower has been meticulously planned, coordinated, and designed from the
ground up, from basic research through thorough design and analysis to contract execution and
construction. Throughout the construction of this building, great consideration is given to the
client's needs as well as the architect's concept, Foster + Partners' originality and innovation,
without jeopardising the project's cost and constructability. The building was eventually awarded
the coveted Green Mark Goldplus grade as well as local Green Building Index (GBI)
accreditation, indicating that sustainability was an essential priority during project
implementation.

Lastly, Daewoo E&C, the main contractor, demonstrated their full capability in completing
the beautiful high-rise building, and DICT, to avoid any potential negative outcomes, Daewoo
Institute of Construction Technology has continued through help the project and the site team,
as well as essential consultants, from tender to completion.

37

Figure 26: Ilham Tower Building

ITEM DESCRIPTION
PROJECT NAME ILHAM BARU TOWER
OWNER OF PROJECT ILHAM BARU TOWER SDN. BHD.
NAME AND ADDRESS OF ARCHITECTURE FOSTER + PARTNERS
CONTRACTOR NAME DAEWOO E&C
CONTRACT PERIOD 58 MONTHS
DATE OF COMMENCEMENT 2010
DATE OF COMPLETION 2017

38

Figure 27: Ilham Tower layout plan

Figure 28: Location of Ilham Tower

39

3.2 PARTIES INVOLVED

Client Ilham Baru Sdn. Bhd. Project Manager Plenitude Builders
Sdn Bhd

Design Architect Foster + Partners Local Collaborating SA Architects Sdn
Architect Bhd

Main Contactor Geopancar Sdn. Bhd. Main Contactor Daewoo Engineer &
(Substructure) (Superstructure) Construction Co.
Ltd.

C&S Engineer TY LIN (International) M&E Engineer Jurutera Perunding
Sdn. Bhd. Valdun Sdn Bhd

Quantity Surveyor Arcadis (Malaysia) Landscape Architect Walrus Design Sdn.
Sdn. Bhd. Bhd.

Lighting Klaasen Lighting Energy & G Energy
consultant Design sustainable design (Malaysia) Sdn Bhd
consultant

Security Certis Cisco Pte Ltd Signage consultant Corlette Design
consultant

Acoustics Acviron Acoustics Interior design Hirsch Bedner
consultants Consultants Pte Ltd consultant Associates Pte Ltd

40

3.3 TYPES/METHOD OF CONSTRUCTION

The contractor employed Semi top-down excavation for the basement excavation of the
Ilham Tower in Kuala Lumpur. Ilham Tower is a skyscraper with 60 storeys and a height of 899
feet. This kind of basement excavation is used to strengthen car parks for office workers and
customers. Because this tower project is located in a densely populated urban area in Kuala
Lumpur city, semi-top-down excavation is suitable. Furthermore, it is appropriate because this
apartment is a very tall building with 60 stories and has a deep basement and underground
features such as car parks, underpasses, and subway stations.

The semi-top-down method combines standard bottom-up excavation with a top-down
building. Bottom-up excavation is used until a specific level of the substructure is reached, then
the floor slab is cast, soil excavation continues under the floor, and permanent structural
components may be created using the top-down construction approach. This strategy, as
compared to the entirely top-down building style, can significantly save excavation time.
Meanwhile, because the floor slab was built before the bottom section of the excavation, the
ground movement support system is stronger.

The building method employed for the Ilham Tower in Kuala Lumpur is a semi-top down
technique. The soils above the substructure's middle floor are excavated bottom-up during a
semi-top-down excavation, and then the middle floor is cast. Once the poured middle floor has
dried, soil removal will continue to the last level. The semi-top-down technique takes less time
than the top-down method because the upper pit is excavated from the bottom up; but, because
the hard middle floor is cast before the lower pit is excavated, the semi-top-down method's
supporting system is stiffer than the bottom-up method. During semi-top-down excavation, soils
above the middle level of the substructure are dug from the bottom up.

After that, the middle floor slab is cast. The soil is removed to the final level when the
poured slab has hardened, and the foundation slab and other subterranean construction
sections are cast. Semi-top-down excavation requires less time than top-down excavation since
the higher pit is excavated from the bottom up. Meanwhile, because the rigid middle floor slab is
cast before the lower pit is excavated, it has a stronger supporting system than the bottom-up
excavation. The semi-top-down excavation was thought to excel in both bottom-up and
top-down excavations.

41

3.4 CONSTRUCTION PROCESS
The building procedure for our chosen local case studies, which is Ilham Tower, uses top-down
excavation as the kind of basement. Because the building process has already been detailed,
the flowchart below will summarise the procedure for both of the local case studies:

Figure 29: Construction Process

42

3.5 SAFETY PROCEDURE

A safety procedure is a detailed plan for carrying out a work procedure. This is used
when a deviation from procedure could result in injury or an accident. The safety procedure is a
document created by groups within the organisation that serves as a template when performing
a specific job task. As for our case study, the chosen project is a high rise building in Kuala
Lumpur, Malaysia, and the method of basement construction used for the project is top down
excavation as it is surrounded by existing buildings.

Firstly, keep the site clean. A messy construction site is a good way to describe the
project site's conditions. Slips and trips may not appear to be a serious issue when compared to
other high-risk activities on the site. It cannot, however, be taken for granted. Slips and trips,
according to the Health and Safety Executive, were responsible for 30% of all documented
serious injuries on construction sites. Workers must keep their workspace clean throughout their
shift in order to reduce the number of slip and trip hazards, according to the rules. For instance,
access and escape routes should not be overlooked and should be given special consideration.

After that, artificial lighting is needed for top-down construction due to the opening on top
being covered by a slab. Machines can only enter through a small opening below ground level.
Poor site lighting increases the risk of injury in a variety of other ways. At all times, all work
areas, access and egress walkways, and passageways must be adequately and safely lit.
Torches or automatic backup lighting should be provided to cover for a failure in the main work's
lighting. Wherever temporary lighting is required, it should include battery backup emergency
lighting, particularly along emergency exit routes.

Last but not least, adequate ventilation is the most important safety that needs to be
encountered as the basement construction is underground. A confined space is any enclosed
area where there is a risk of death or serious injury from hazardous substances or dangerous
conditions. Due to the limited access for oxygen to lower ground, top-down excavation requires
a blower. As a result, this blower will transport oxygen from the upper level to the basement
level, preventing workers from fainting due to a lack of oxygen.

43

The risk is greatest in below-ground areas with poor natural ventilation, such as tunnels
and excavations, as well as in enclosed spaces. Air quality can be harmed by a slight decrease
in oxygen proportion or the presence of a harmful gas can affect the people especially workers
without the warning. In a nutshell, the safety guideline for all construction works was created as
a guide for proper planning and control of developments involving the construction of
basements and deep excavation.

44

3.6 PROBLEMS OCCURED

In the construction industry, problems or issues that occur during the construction works
are quite common. It depends on how the construction management manages the problems
and issues. While IB Tower is being constructed, there were a few problems that occurred
during the construction. The first problem that occurred was the high level of groundwater. This
problem was discovered during the excavation of columns. Since basement construction is
frequently submerged below the supported groundwater table, the excavation process is quite
difficult and risky. Therefore, when deciding on the method of excavation and the construction’s
design, the level of groundwater in the underground space becomes one of the most crucial
factors to take into account. So, investigating the soil condition at the construction site is really
important in determining the ground condition.

Other than that, congested area and limited space is also one of the problems that IB
Tower needs to be faced during the construction. As mentioned in the background of the case
study, the site location of IB Tower is at the centre of Kuala Lumpur which is known as a bustling
area. Therefore, due to heavy inbound traffic during peak hours especially weekdays, the
construction process which required transportation was hampered. Due to lack of space on the
project site to designate a disposal area for the removal of excavated material work, the major
restriction is to move excavated material from basement excavation to a location of a disposal
area that is located off-site.

Lastly, the problems that occurred during the excavation of the IB Tower basement is the
ground movement. During the temporary excavation stage and the operating stage, the
groundwater level dropped, which resulted in the movement of the soil. Due to the construction
site's location in an urban region that is bordered by other structures like hotels, retail stores,
and institutions, it has had an impact on the nearby properties as well as subsurface utilities.
Therefore, it is crucial to keep an eye on the groundwater level when excavating and installing
the necessary dewatering equipment to drain the water.

45

3.7 STEPS AND SOLUTIONS TO SOLVE

Every problem or issue has its own problem and solutions. It depends on how their
management handles the problem and issues. In the construction industry, they have long
struggled with numerous unanticipated issues. Therefore, ongoing attempts have been made by
the relevant professionals to propose fresh and efficient approaches to tackling problems. So,
there are a few ways that can be used to solve the problems or issues.

The first solution can be used by putting in top-down floor slabs and a Secant Pile Wall
for the basement. This solution can solve the problem of ground movement that occurred at the
construction site. This solution can be used not just as temporary shoring systems but also as
permanent shoring systems. Therefore, since Secant Pile Walls can support the entire structure
while the superstructure is being erected concurrently, using them for this project is highly
advised.

Other than that, rescheduling for transportation works is also one of the solutions that
can be used for the second problem. The project manager should have a solid strategy for entry
and egress for the transportation and advocate transporting materials to the construction site at
night when there would be less traffic because there is only one access route accessible in
order to avoid incoming traffic during those working hours. Other than that, due to the limited
space of the construction site itself, the project manager should budget for the additional loading
trucks to be on standby every hour for the removal of the excavated materials. But, it is advised
to schedule the removal of excavation material during off-peak hours and complete the
excavation operations at night.

Last but not least, for the problem of high levels of groundwater, they can use a drained
raft system as a solution. By using a drained raft system with a passive pumping system and
recharge wells to control the reduction of groundwater in place of tension piles and thick
basement slabs. Water from the basement slab and subsoil collection piles is drained into sump
pits by a drained raft system.

46

4.0 COMPARATIVE STUDIES
4.1 SIMILARITIES

SIMILARITIES MERDEKA 118 ILHAM BARU TOWER (IB)

Large Scale of Both case studies feature structures that span a huge amount
of land and reach a towering height of the building which is
Construction defined as a skyscraper in Kuala Lumpur.

High Initial Costs They have incurred substantial construction costs because of
their large-scale commercial development efforts.

Limited On-site Area Having the same problem which is to keep their supplies,
Available equipment, and machines simultaneously was harmed.

High Expenditure of the As a result of their high cost and limited storage capacity,

Project these materials need considerable transportation

expenditures when transported in stages.

Location of Project As both case studies are in Kuala Lumpur which is known as
city inhabitants, the placement of these structures posed a
transportation challenge, affecting both on - and off-site
material delivery.

47

4.2 DIFFERENCES

MERDEKA 118 DIFFERENCES ILHAM BARU TOWER (IB)

Merdeka 118 (previously known Project Background The structure has 58 floors in
as KL 118 and Warisan Merdeka total. The structure, which
Tower) is a 118-story, stands 274 metres (899 feet) ,
678.9-metre (2,227-foot) super was also the seventh tallest
tall skyscraper presently under skyscraper in Malaysia. The
construction in Kuala Lumpur, 60-story Ilham Tower houses a
Malaysia. Grade A office suite, a 4-star
hotel, an art gallery, a gift shop,
and food and beverage outlets
with 4 basements.

Traditional top-down and Method of Construction The semi-top-down
bottom-up construction method. construction method.

The first step in the building Construction Process 1. Excavation

process, followed by the 2. Checked an adequate

installation of load-bearing support is in place

components. 3. Started with

1. Construct retaining walls underpinning and piling

2. Next, construct a column 4. Construct retaining

3. The first level of walls

basement is excavated 5. Next, put a layer of

4. Construct a slab for a first waterproofing

basement level 6. Lastly, pouring concrete

5. Synchronous base will be utilised.

footing construction.

48

MERDEKA 118 DIFFERENCES ILHAM BARU TOWER (IB)
Safety Procedure
The Merdeka 118 Tower project Ilham Baru Tower (IB)
uses a diaphragm wall to Problems Occured necessitates the use of a
maintain soil pressure, with a blower due to the lack of
wall thickness of up to 800mm oxygen in the lower ground. As
and the need for additional a result, this blower will
reinforcement for lateral force transport oxygen from the
resistance in the permanent upper to lower levels,
slab. preventing workers from
fainting due to a lack of
1. The project needs to be oxygen.
stopped due to the
Movement Control Order 1. High level of
(MCO) that leads to an
extension of time. groundwater during the

2. Faced the same excavation of columns.
problems as IB which is
limited space and 2. A congested area and
congested areas. limited space for
construction.
3. Noise pollution is a
widespread issue that 3. The ground movement
affects practically all
construction projects. that resulted from

groundwater level

dropping.

49