Structural Design Post Mortem

STRUCTURAL
DESIGN POST
MORTEM
GROUP MEMBERS
1. Christal Wong Ching Ling 0326715
2. Ahmad Nabil b. Jimi 0327780
3. Yeoh Han Joo 0330959
4. Mohammad Harris Bin Haji Abdul Aziz 0323219
5. Koh Jing Fan 0330792
6. Ranjeev Singh 0327812
Lecturer: Mr. Mohd Adib
BSC (HONS) IN ARCHITECTURE
BUILDING STRUCTURE (BLD61003)

Forewords
This report is on the Structural Design of the Visitor Interpretive Center chosen from our
previous Studio III’s design project. This post mortem report assesses the structural design
of the VIC, and proposes amendments to improve the structure as a whole through
structural knowledge obtained from the course.
The approach of this report is firstly to present a structural analysis (Section 4.0) on the
existing structure of the VIC in terms of its safety, feasibility, economy, optimization,
integration, stability, strength and rigidity. Under each analysis problem areas of the
structure are highlighted.
Under Section 5.0 of the report, the previously highlighted problem areas of the structure
will be discussed and amended in detail. Relevant drawings and examples are inserted for
reference and graphic understanding. After the amendments the structural analysis are
related back to the aforementioned problems encountered.
We would like to express our gratitude towards our lecturer, Mr. Adib for his guidance and
assistance in helping us completing the report. Our groupmates Christal Wong Ching Ling,
Ahmad Nabil b. Jimi, Ranjeev Singh, Koh Jing Fan and Yeoh Han Joo and Mohammad
Harris Bin Haji Abdul Aziz have contributed evenly to produce this report to the best of our
abilities.

Table of Contents
1.0 Introduction of Building
2.0 Original Building Drawings
2.1 Plans
2.2 Elevations
2.3 Sections
3.0 Existing Structural System
3.1 Structural System of the VIC: Composite Construction
3.2 Materials
3.2.1 Reinforced Concrete
4.0 Structural Analysis
4.1 Safety
4.2 Feasibility
4.3 Economy
4.4Optimization
4.5 Stability
4.6 Strength
4.7 Rigidity
4.8 Summary
5.0 Proposed Modifications
5.1 Foundation
5.2 Columns
5.3 Beams
5.4 Walls
5.5 First Floor Slab
5.6 Cantilever
5.7 Roof Slab
5.8 Egg-crate
6.0 Modified Drawings
6.1Plans
6.2 Elevations
6.3 Sections
7.0 Load Distribution
8.0 Conclusion
List of Figures
Referencing
1-3
6
7
7-9
10-11
12
13-14
15-22
23-25
26
27-28
28-32
33-35
36
37
38
39-41
42-47
48-51
52-57
58-59
60-61
62-64
65-66
67
68
69

1

Sungai Buloh Leprosy Settlement is the second largest Leprosy settlement in the world.
It was the most modern leprosarium in the British commonwealth. Hence, the project is
to build a visitor interpretation centre (VIC) for the historic Leprosy Settlement. The
concept that is chosen for this project is the Journey of acceptance of those who are
affected by the leprosy. Being the so called outcast of the society,these people crave
for acceptance. Along the way these people were isolated and have to adapt to a new
environment.
The Journey
the entrance is divided into 3 parts. This will separate the journey of people that
represent isolation. After isolation, the users experience bigger spaces which represents
adapting. Huge glasses of windows facing the centre of the building will get enough
daylight to achieve desirable ambience in the spaces. The Journey continues with a
guide of the openings. The openings are arranged like gills which creates an illusion to
keep the users to keep moving forward .
Figure 1.1.1 entrance view of the VIC
Figure 1.1.2 rear view of the VIC
2

The facade of the entrance is shaded by blocks,
eggcrate-like shading structures. It’s rigid and grid
shield represents the barrier of those who are
affected from the outside world.
These fins wall on the building are used for cross
ventilation and also brighten the spaces. It is
located at the main part of the building. The fins s
also promotes the movement of going forwards
as the lights are guiding users to the exit.
Figure 1.2 : the facade of the building
Figure 1.3 : 1st floor plan of the building to showcasing the fins .
3

The first floor of the building is slowly
sloping upwards. This represent the
journey to a higher place which is to be
accepted . The height of the ceiling is
also increasing when reaching the end
of the journey to increase the
comfortness of the users
Figure 1.4: ground plan of the VIC
Figure 1.5: first floor of the VIC
Figure 1.3 : the roof and floor slabs of the building
4

Figure 1.6 : Front elevation
Figure 1.7: North elevation
Figure 1.8: West elevation
Figure 1.9 : East elevation
5

2.0 Original Building Drawings
6

3.0 Existing Structural System
The existing structural system of the VIC is a composite between load-bearing wall structure
and frame structure. This means external walls are treated as load-bearing walls while
intermediate supports lie in the form of reinforced concrete columns. This type of structure
works for building with large spans, in this case the VIC which spans an elongated form.
3.1 Composite Structure
Load-bearing
walls
Columns
The load-bearing walls in the existing structure serve to withstand the load from the above
exhibition area, the balcony and as walls for the washroom. Columns were added loosely
to offer extra support.
Materiality
The structural components of the VIC are all made of reinforced concrete. Apart from
being a suitable candidate for load-bearing purposes, it aligns with the aesthetic and
concept with the VIC as a visitor interpretive center for its poetics. More will be elaborated
on reinforced concrete in the next section.
Figure 3.1.1: Load-bearing walls and columns on the ground floor
Figure 3.1.2: Load-bearing walls on the first floor
Figure 3.1.4: Example of a framed
structure building (Civil Digital, n.d.)
Figure 3.1.3: Example of the load-bearing
structured building (The Constructor, n.d.)
7

Structural Components
Load-bearing walls
Unlike conventional load-bearing wall structures, the load-bearing walls in the VIC do not
serve to act as walls to segregate spaces into compartments. The load-bearing walls on
the ground floor were only added to provide support for the above spaces. The
load-bearing walls will always carry the live and dead load from members above, and
cannot be altered after completion of construction.The disadvantage of utilising
load-bearing walls in this way is that if the load-bearing walls collapse, it will lead to the
collapse of the structure above. The use of load-bearing walls is also costly as the large
area of load-bearing walls require more material to build, raising the costs of material and
also labour as well.
The use load-bearing walls on the first floor is regarded as unfavourable as load-bearing
walls add high amounts of dead load to the first floor slab and subsequent structural
members beneath. It is also uneconomical due to similar reasons as discussed above.
Figure 3.1.5: Load-bearing walls in north elevation view
Columns
The existing columns in the VIC only go up to the first floor slab and do not extend
upwards until the roof (Figure 3.1.4). The columns were added to support the seemingly
heavy and large spanning first-floor sloping slab. Reinforced concrete columns are
excellent in withstanding external loads like compressive, tensile, torsion, shear and also
moment, making them superior than load-bearing walls in the event of seismic activity.
They also provide more flexibility in spatial planning, with walls added be able to serve as
only partition walls and can be altered. Cost is reduced along the reduction of material
usage. The use of columns in the VIC allow for structural support for the first-floor slab,
but also do not limit visibility and permeability on the ground floor of the VIC, which will
not be achieved by placing load-bearing walls as support structures.
Figure 3.1.6: Columns extending up to the first floor slab
(South Elevation: Steel louvres and Curtain wall removed)
8

Conclusion
The structural system of the VIC is mostly following conceptual design and aesthetics, and
thus unlike conventional mass-produced buildings with a structural system like rigid frame
or a normal load-bearing/mass wall construction.
To conclude the existing structure of the VIC, it does not have an organized structural
system, and seems as if its an afterthought and not pre-planned from the start of the design.
This can be seen in the random and unorganized placement of the columns. The overall
structure is also insufficient in supporting the loads of the roof as well, in addition to the
absence of support for the cantilever on the side. Detailed errors and improvements will be
talked about in section 5.0 of the report.
However, the columns do not have an organised arrangement, with a very loose grid
arrangement. Columns were only added to support certain points thought to need some
form of load-transfer down to the ground. In this manner, load is unable to be distributed
evenly and transferred. More on the errors in the columns have been given a dedicated
section on section 5.2 of this report.
9

3.2 Materiality
Reinforced Concrete
As shown in diagram 3.1.1, the structural components of the VIC are the load-bearing walls
and columns, with the absence of beams. All structural components highlighted have the
same material, which is reinforced concrete. In this section, the general properties of
concrete as a structural material will be discussed. Specific analysis on the material were
applicable will be discussed in separate topics under section 4.0 structural analysis.
Introduction
Reinforced concrete was invented in the 19th century, and has since revolutionized the
construction industry - becoming one of the world’s most common building materials.
Reinforced concrete refers to concrete embedded with steel in a manner that two
materials join to act together to resist forces. The reinforcing steel bars in the concrete
(rebars) absorbs the tensile, shear and occasionally compressive stress in a concrete
structure. The addition of steel bars is due to the weak nature of plain concrete which does
minimal contribution in withstanding tensile and shear stresses caused by wind,
earthquakes, seismic vibrations and other forces. After concrete is reinforced, the tensile
strength of steel works together with the compressive strength of concrete to allow the
structural member to sustain these stresses over considerable spans (Chauhan, Tikkanen &
Kuiper, 2012)
Advantages of Reinforced Concrete as a Structural Material
1. Reinforced concrete possess high compressive strength compared to other building
materials.
2. Reinforced concrete is able to withstand good amounts of tensile stress due to the
addition of reinforcement bars.
3. Reinforced concrete have adequate fire and weather resistance.
4. The durability of a reinforced concrete building system is better than any other building
system.
5. Since reinforced concrete component are constructed in molds, it can be economically
molded into a limitless range of different shapes, and is widely used in precast structural
components.
6. The maintenance cost of concrete is low. Thus, using reinforced concrete is the most
economical option as a construction material.
7. The use of reinforced concrete provides rigidity to the structure, minimizing deflection.
8. Reinforced concrete structures require less skilled labor compared to steel structures.
(Civil Engineering, n.d.)
10

Figure 3.2.1: Concrete pouring process in the construction of reinforced concrete (R Bray
Groundworks. n.d.)
Disadvantages of Reinforced Concrete as a Structural Material
1. The tensile strength to compressive strength ratio of reinforced concrete is
one-tenth.
2. The mixing casting and curing of aggregates making up the concrete are crucial in
affecting the final strength of the reinforced concrete.
3. The use of reinforcement bars increases the probability of cracking due to the
shrinkage and creep in freshly laid concrete and hardened concrete (Engineering
Intro, n.d.).
11

4.1 Safety
The design and safety of a building is the primary goal of clients. A building’s safety should be
heavily considered from the preliminary stage of design, during construction of building and
even when it is occupied by users.
Current dangers and potential threats :
1. Irregular and Disturbed Load Distribution
Each 300mm x 300mm columns are aligned irregularly and not parallel to its pair.
Furthermore, weight of roof is not distributed to foundation due to the height of column
only reaches to the 1st floor slab.
Potential Threat From Irregular Load Distribution
The distribution of load from roof slab is to foundation is disturbed due to the arrangement
of columns.. Building may collapse if there are unforeseen accidental load acting on weak
points of the building or if building experiences ground settlement.
Figure 4.1 :
Ground floor plan (before amendments shows the absence of grid system & missing columns
Figure 4.2 :
Section shows the cantilevered floor slab does not have structures to support its weight.
Overall lack of detailing of reinforcement in RC structural members and joints.
13

2. Materiality of Building (diagram showing materials)
Glass and steel curtain walls frame up the ground floor as non-load bearing walls.
While the 1st floor and roof consists of precast concrete slabs.
Potential Threat(s) From Choice of Materials (Too heavy , Fire safety)
Dead load of building such as the unibody concrete roof slab and floor slab acting
onto ground floor’s glass walls with steel mullions may cause severe structural
failures as glass and steel frame are not load bearing materials.
Moreover, steel loses 50% of its strength at 650°C. .
3. Fire Safety of Building
In reference of UBBL 1984, By-law 158 (3), 224, load bearing structures of the building
- columns, floor slab and roof with the thickness minimum of 180mm of unplastered
concrete has a minimum Fire Rating Period of 4 hours;
Hence it is a safe choice of using concrete for main structural components.
Figure 4.3.0 Ground Floor Plan (Before Amendments)
Figure 4.3.1 Section of Building (Before Amendments)
Non-load bearing
glass walls are
unable to support
the load from above.
Location of curtain
walls with steel
mullions
Summary
Safety of building is determined by the ability to withstand and transfer loads such
as dead load from its own structures , live load from occupants, accidental load and
seismic load. The safety of building is much affected by the choice of materials and
methods of distribution of loads. Occupants in building may be harmed by the
cracks or breaking of building structures by careless choice of building materials or
uneven load distribution.
14

For any architectural design, prior to construction, a feasibility study or analysis is required
to ensure that the design can be physically constructed through the most convenient and
practical way possible.
Current feasibility issues to address:
Structural Components:
● Walls
○ The VIC consist of both bearing and non-load bearing walls that are not ideally
placed throughout the building. In addition to that, the type of materials
proposed for the walls pre-modification also impacts the overall structural
integrity of the building as a whole, which may result to structural failures and
even collapse.
○ The method of construction has also changed according to the type of wall
being erected,
● Columns
○ Aside from load bearing walls, columns can be seen throughout the VIC to
suggest support and equal or even load distribution. At its pre-modification state,
the number and placement of columns are not sufficient to bear the full weight
of the VIC.
● Floors
○ The proposed floor type pre-modification is reinforced concrete floors and is
kept the same due to it being the most applicable type of floor construction for
the VIC.
● Ramp
○ A narrow linear unibody reinforced concrete slab is used as a ramp to connect
the first floor to the second floor which is proven to be problematic to construct
due to the lack of structural support to keep the ramp from collapsing due to its
own weight.
● Roof Slab
○ Roof slab is maintained as a reinforced concrete slab but is made thinner hence
lighter without having to compromise its structural integrity.
4.2 Feasibility
15

Non-load bearing
Load bearing As seen on figure 4.2.0,
the ratio of load
bearing to non-load
bearing walls are not
proportionate. With the
consideration of acting
loads from floor slabs
and roof slab, it is
within reason to
assume that due to the
disproportionate ratio,
acting loads are not
distributed evenly.
In figure 4.2.1 shows
that there are load
bearing walls that act
as fins to allow light to
enter through the gaps
between the walls. The
apparent issue is that
there are no structural
support to distribute
the loads from the first
floor fins down to the
foundation.
Figure 4.2.0 Ground Floor Plan
Figure 4.2.1 First Floor Plan
Figure 4.2.2 Elevation Drawing
1. Walls: Load bearing to Non-load bearing
ratio.
16

Walls: Material & Construction.
The supposed wall type used in the pre-modified VIC is not suitable to provide structural strength
to support the the building’s weight. To counteract this flaw, we analysed the contributing factors
to potential structural failures:
Factors:
● Material
● Method of construction
● Placement
The initial proposed wall material in the building’s pre-modified state were bricks due to the the
ease of constructing single layer brick walls.
As seen in figure 4.2.3 the red boxes show the portion of the building that primarily consists
of the aforementioned non-load bearing masonry walls. From here it shows that this part of
the building is lacking the necessary structural support and so concluded that the
placement and material of wall is no longer feasible in the design of this building. Hence by
changing the type of materials and method of construction used for non-load bearing walls
into structural walls to carry the weight of the building from the roof and upper floor, all the
way down to the foundation.
The highlighted walls in Fig. 4.2.3 are proposed to be modified into load bearing walls to
further support the upper levels including the roof slab and the proposed change in
material is from non-load bearing masonry or single layered brick walls into reinforced
concrete walls.
Thickness: 110 mm
Single Layer Brick Wall
(Pre-modification):
Brick
Figure 4.2.4
Figure 4.2.3
Ground Floor First Floor
17

Walls: Fins
Seen in figure 4.2.4, the highlighted walls in purple are fin walls designed to allow light
entry into the first floor. The issue with these walls is that they are made of heavy masonry
which is not practical considering that in the pre-modified design, there are not sufficient
enough support from the ground floor to transfer the wall loads alone down to the
foundation.
In addition, these walls are heavily concentrated along the one side of the building
(highlighted in red box), that alone shows the uneven load distribution without the
consideration of structural support for the lower level of the building.
Even with the additional structural walls and columns in the post-modified design,
changing the wall type into something more lighter and convenient to construct is
preferred as the modification will not affect the functions of the fin walls. Instead would
lower spending costs on material and construction, whilst at simultaneously making the
design more feasible.
Figure 4.2.5 First floor
18

Figure 4.2.6 shows the ground floor plan with the existing pre-modified columns highlighted in
red, and an arrow pointing to a glass curtain wall. From here, it is apparent that the columns are
placed in areas which do not have structural walls in an attempt to support the upper level but
still not sufficient to provide the much needed support.
It is also important to note that there are only one column on each side of the glass curtain wall
acting as support, which is still a major weak point of the VIC in its current pre-modified state.
Figure 4.2.6
In the pre-modified VIC, the number of columns are not sufficient to provide support to
the upper level of the building, in addition, the location or placement of said columns
are not ideal nor convenient in making sure that the building’s design feasible.
Factors:
● Number of columns
● Column placement
2. Columns.
19

3. Floor slabs.
Reinforced concrete floors were used in the pre-modified state of the building and we
decided to maintain it due to the suitability and applicability of the material and method
of construction that falls in line with the feasibility of the design.
The method of construction is in-situ as opposed to pre-fabricated reinforced concrete,
this is because it is more economical in this application especially because the VIC is
one of its kind and not mass produced. Most pre-fabrication methods are affiliated with
mass production in order to save time and cost in relation to supplying for the demand,
whereby for the VIC, it is not necessary.
Diagrams below (figure 4.2.7 & 4.2.8) show the general outline of the reinforced concrete
slabs, as can seen that the shape of the slabs are not confined to one shape though it is
angular. So using in-situ method of reinforced concrete, after placing down the
formwork and reinforcement rebars, concrete can be poured into the formwork either
by segments/portions or altogether simultaneously and cured.
Figure 4.2.7 Ground Floor
Concrete Slab
Figure 4.2.8 First Floor
COncrete Slab
20

4. Ramp.
As shown in figure 4.2.9, the ramp is a unibody reinforced concrete slab that is worth
240,000 mm long, inclined at an angle of 6 degrees, connecting the 1st floor to the 2nd.
From the sheer distance covered by the ramp alone is already not feasibly done
without any structural support from underneath i.e. columns and beams.
Especially when the ramp is made out of reinforced concrete, structurally on its own
will not be able to withstand the stress due to its own weight and potentially fail when
forces act on it due to compression.
1st
Floor
2nd
Floor
From figure 4.3.0, shows that there are no structural support such as columns,
underneath the ramp. Which will be addressed in the following post-modified version
of the building design.
Figure 4.2.9 First Floor Plan
Figure 4.3.0 Section
240,000 mm
21

Similar to the floor slabs, the roof is also made out of a unibody reinforced concrete slab.
Though due to it being used as a roofing material, the main concern in the VIC’s
pre-modified state is that the slab itself may be too heavy to be used especially with the
lack of structural support to transfer loads directly down to the foundation.
Aside from the need for structural support, it is feasible for the material to be used as
the final proposed roofing material in post-modification for as long as the structural
issue is addressed.
5. Roof Slab.
Figure 4.3.1 Section
Shown in figure 4.3.1, the lack of any structural support to transfer loads from the roof
directly to the foundation, though there are structural walls supporting the roof itself.
Overall, the feasibility of the VIC in its pre-modified state is questionable due to the
aforementioned structural and material issues but the design on its own is very much
feasible.
In its pre-modified state, the lack of structural support systems such as columns, load
bearing walls, beams .etc has proven to be detrimental to the overall structural integrity
of the building but no major changes are needed to be made to the building’s design
that would compromise the aesthetics and the intended building’s design, hence the
original idea and narrative that inspired the design is still very well maintained if not
improved.
Summary
22

4.3 Economy
Construction economy is the careful management of available sources and methods
during a construction process as a significant process during the planning procedure to
maintain a good balance between the client’s expectation and budget (smart sheet. n.d.)..
Main costing components :
Formwork
Formwork costs on average are approximately 50 percent of the cost of the completed projected.
For that reason, it’s important to follow a cost efficient guideline in this aspect (concrete reinforcing
steel institute, n.d.).
Structural system
The complexity of the structural system determines rate of cost. A simpler system results in
cheaper ratings. Therefore, a well thought choice of structural system that satisfies both the
economics and sufficient load support should be considered.
Materials
The materials specified have an important bearing on the cost of the project. This deeply depends
on the client’s approach to the outcome. Materials are well advised to be obtained from local
grounds instead of foreign materials as it’s more cost efficient and considered a step towards
environment sustainability (concrete reinforcing steel institute, n.d.).
Labour
Determining the labour cost can be varied into the period of construction and also complexity of
workmanship. A higher paid craftsman is required for a more complex yet quality controlled result.
Nevertheless, the longer period of construction increases the salary of the labour workers.
23

Structural system
Economically inefficient traits Economically efficient traits
No specific framing system
An incomplete preliminary design results in
inability to establish the quantity and cost of
a project
Impractical weight ratio between ground
and first floor
This trait results in a more advanced
support system that requires higher cost of
materials and skilled labour work
Economy aspect of the existing VIC :
Formwork
Irregular column arrangement (Figure 4.3. )
Irregular arrangements is categorised as a
confusing layout and causes inconvenience
and unnecessary mistakes in construction.
Standard rectilinear form (Figure 4.3. )
Rectilinear form is the easiest, fastest and
cheapest labour formwork
Difference in height of the vertical louvered
walls (Figure 4.3. )
Unstandardised wall dimensions increases
the amount of drawings, measurements,
materials and labour cost
Figure 4.3.1 Irregular Column Arrangement
Figure 4.3.2 Difference in height of vertical louvered walls
Figure 4.3.3 Standard Rectilinear Form
2218
3450
24

Utilizing concrete as main building material
Concrete itself is one of the cheapest
building material
Very consistent use of materials
The consistency decreases spending in
sourcing for various materials and also less
complex for labour work
Reinforcement utilising rebar
Rebar is the cheapest form of rolled-steel
Materials
List of aspects that requires improvements
1. Column systems
(refer to pg… ‘Column’)
2. Fin walls’ dimensions
(refer to pg… ‘First floor walls’)
3. Framing system
(refer to pg… ‘Slab’, pg… ‘beams’, pg… ‘column’)
4. Weight ratio on both floors
(refer to pg… ‘First floor walls’ , pg… ‘Roof’)
Labour
Confusing structural system and building
framework
Either a longer construction period is
needed or more skilled labour work would
be hired, both increasing the cost
Common concrete work
Concrete work is one of the basics in
construction. Not much skilled labour
workers are needed
25
Summary
Economy of building is highly affected by the decisions made during the
pre-construction planning process and also acts as a huge aspect that always
becomes the factor of debates in construction choices. Therefore, careful and wise
planning of the form, structural system, materials, construction schedule, etc, should
be implemented to achieve a better balance between the budget and clients’
expectants. The overall economy aspect of the VIC stresses on the inefficient parts.
There are many other ways that can potentially improve the economic traits of the
VIC.

The building’s structural design is not optimized to serve for the intended purpose of being
a visitor’s information centre but it is primarily designed for users to ‘experience’ the spaces
as opposed to ‘efficiently utilising’ the spaces. The aspect of optimization in building design
is often undermined or if not at all overlooked, because a designer’s wants many not
necessarily be the essential needs.
Factors such as Safety, Practicality, Quality, Feasibility and Economy are important aspects
in a building’s design but not always the first aspects to consider in the first few stages of
design, usually it is the Aesthetics, Grandeur and the overall look of the building. Naturally,
because it is every designer’s want to design an interesting looking building that would
serve for a very particular purpose and in turn would attract potential users due to the
design’s uniqueness and individuality, as opposed to design a regular and generic
conventional building that can be used for almost any purpose despite the context, such
as a multipurpose hall.
The same can be said for this VIC, the aesthetics of the building is made priority which
compromised other aspects of the building, hence this issue is addressed in the
post-modification version of the building.
4.4 Optimization
26

4.5 Stability
The importance of stability and the resistance to horizontal forces imposed on a building
often do not receive the same attention as does the analysis for vertical forces. For all
structures, it is essential that there be a path passing through clearly defined structural
members by which the stabilising forces and horizontal forces may be transmitted to the
foundations.
Instability could result to catastrophic breakdown which must be seriously considered in the
early stages of the design process.
4.5.1 Forces affecting the stability of the VIC
1.Live Load
Live loads include any temporary or transient forces that act on a building or
structural element. Typically, they include people, furniture, vehicles, and almost
everything else that can be moved throughout a building.
2. Dead Load
Dead load refers to loads that relatively don’t change over time, such as the weight of All
permanent components of a building including walls, Beam, columns, flooring material
etc)Fixed permanent equipment and fitting that are an integral part of the structure.(like
plumbing, HVAC, etc.)
4. Wind Load
Uplift load - Wind flow pressures that create a strong lifting effect, much like the
effect on airplane wings. Wind flow under a roof pushes upward; wind flow over a roof
pulls upward.
Shear load – Horizontal wind pressure that could cause racking of walls, making a
house tilt.
Lateral load – Horizontal pushing and pulling pressure on walls that could make a
house slide off the foundation or overturn.
3 Lateral Forces
Lateral loads are horizontal forces applied to a structure at its rigid joints and cause
deflection. Example of lateral forces are: wind, earthquake, and explosions. Their
applications takes different forms. It can be instantaneous, viberatory, or monotonous,
etc.
1
4
2
3
Figure 4.5.1: Types of Load Imposed (South Elevation with Louvres removed)
27

The capability of a structural system to transmit various loadings safely to the ground is
the key in ensuring the stability of a structure and. The direction of load transmision
follows the gravitational pull from the ground A series of building components are
required to depend on each other to form a structure that is able to transfer load.
Load transmission
Building structural components required for the stability of a building
● walls
● Columns
● Beams
● Foundation system
Centre of gravity
The centre of gravity is a certain point
in the structure that the mass of the
structure is evenly distributed
around.
The centre of gravity has to be
located and identified in order to find
out if the building to be stable. The
lower the centre of gravity, the higher
the stability of structure
Figure 4.5.2
28

4.6 Strength
What is strength of a building?
Strength is the capacity of the individual elements, which together make up a structural
system, to withstand the load that are applied to them.
What happen if the strength of a building is weak?
The building will collapse resulting from incapable of withstanding massive load or
natural disaster.
Factors affecting the strength of a building.
The strength of a building is linked with the stability and rigidity. As a means to achieve a
sufficient strength, the Building structure is a vital aspect to be consider closely. The type
of building structure will depends on the design of the building whether it fits grid
structure, frame structure or shell structure. A building requires a support system that
has sufficient strength to enable to transfer loads and forces on the structure to maintain
its stability.
Current Issues on the building
External loading
Load-bearing structural members support or transfer loads on the structure is not
equilibrium with each other due to:
1. No specific framing system
2. Irregular placement of columns and absence of beams
Figure 4.6.1: [ section from east ] the current
load distribution without beam
Figure 4.6.2 : flat slab without beams
Figure 4.6.3: [ section from south ] the current load distribution without beam
with irregular placement of columns.
29

Figure 4.6.4: ramp that leads to first floor of the building.
The strength of the ramp towards the first floor of the VIC is very weak as there is no specific
structure that is supporting it. The landing floor slabs is supported by concrete load-bearing
below it with the absence of beams. There is also no columns that supporting the concrete
floor slabs, This insufficient structure strength will likely to cause the structure to collapse.
Concrete roof slab
Masonry wall
Concrete Load-bearing wall
Concrete slab floor
Figure 4.6.5 : [ east section ] structure of the ramp leads to first
floor.
30

Internal Forces
The failure can vary according to material type and design methodology. Internal stresses
can change the shape of a structure which also known as deformation due to:
1. Tensile strength of concrete
2. Compressive strength of concrete
3. Shear strength of the concrete
The most common structural element that is subject to bending moments is the beam,
which may bend when loaded at any point along its length. However, in this VIC case,
structural element that is likely to bend is the floor slab because of the absence of
beams in the building structure. The tensile performance ; strength and deformation of
plain concrete can be greatly enhanced using steel fibers. The increment depends on the
dosage and the type of the steel fiber.
Compression force
Tension force
Figure 4.6.7 : [ south section ] bending of the floor slab with combination of tension
and compression forces in the VIC building.
Figure 4.6.6 : diagrams of internal force acting on a
concrete structure (Design and Control of
Concrete Mixtures, n.d.)
31

Strength of Concrete
Concrete strength is affected by many factors, such as quality of raw materials,
water/cement ratio, coarse/fine aggregate ratio, age of concrete, compaction of
concrete, temperature, relative humidity and curing of concrete.
Quality of Raw Materials
Cement: Provided the cement conforms with the appropriate standard and it has been
stored correctly (i.e. in dry conditions), it should be suitable for use in concrete.
Aggregates: Quality of aggregates, its size, shape, texture, strength etc determines the
strength of concrete. The presence of salts (chlorides and sulphates), silt and clay also
reduces the strength of concrete.
Water: frequently the quality of the water is covered by a clause stating “..the water
should be fit for drinking..”. This criterion though is not absolute and reference should be
made to respective codes for testing of water construction purpose.
Water / Cement Ratio
The relation between water cement ratio and strength of concrete is shown in the plot as
shown below :
The higher the water/cement ratio, the greater the initial spacing between the cement
grains and the greater the volume of residual voids not filled by hydration products. There
is one thing missing on the graph. For a given cement content, the workability of the
concrete is reduced if the water/cement ratio is reduced. A lower water cement ratio
means less water, or more cement and lower workability.However if the workability
becomes too low the concrete becomes difficult to compact and the strength reduces.
For a given set of materials and environment conditions, the strength at any age depends
only on the water-cement ratio, providing full compaction can be achieved.
Figure 4.6.8 : diagrams on relation between cement ratio
and strength of concrete
32
Summary
Strength of the building is affected by the structure, materiality and types of construction.
These factors are the main elements for the building to withstand the forces and loads that
applied on it .Therefore, strength of a building is important factors in general as it has
relation with safety, stability & rigidity.

4.7 Rigidity
Introducing Rigidity
In definition, rigidity is the property of a material to resist deformation under the action of an
applied force ensuring that it does not bend or flex (Designing Buildings Wiki, 2018). The
rigidity of a structure ties closely with the flexibility of the structure. The more rigid a
structure is, the less flexible it is. Rigidity is a function of the material (E) and geometric(I)
properties of the structure (Maran, 2017). Structural calculations allow precise control on
structural rigidity in buildings, which is preceded by load assessment to be carried by the
structure (Shahul, 2016).
The rigidity of a structure is determined by material properties and geometry. Thus, the
design of the shape of the structure is crucial in determining the rigidity and to avoid
structural collapse.
Theory of Triangulation:
The theory of triangulation involves using triangular shapes to enhance the rigidity of the
structure. The triangulation method is often added to squares or cubes by adding a diagonal
support across two corners, producing two triangles linked together. This method - bracing
is used in framed structures relating particularly to hinged or pinned structures (Build Right,
n.d.).
A rigid structure features elements connected to each other at their ends with joints that do
not allow any relative rotation to happen between the ends of the members. There is
minimal flexibility in rigid structures. The dynamic response (natural frequency) of the
structure depends on the rigidity of the structure. The flexibility in buildings is important for
their role in seismic behaviour. In an event of an earthquake, for flexible buildings, different
parts of the building will move back-and-forth in different amounts (Murty, n.d.). However,
in rigid buildings, every point in the building will move the same amount as the ground. Tall
buildings are more flexible than short buildings due to its height and mass, and will take a
longer time period to stop moving in the event of seismic activity.
Figure 4.7.1: Forces acting to deform a polygonal
shape structure (“Rigidity”,n.d.)
Figure 4.7.2: Added bracing to increase rigidity
which resists deformation (“Rigidity”, n.d.)
Figure 4.7.3: Different buildings respond differently to the same ground vibration
(Murty, n.d.)
33

Rigidity in the VIC
Overall: In assessment, the VIC itself employs a mass wall construction, as discussed in
section 3.0 (p.x). Mass wall construction features load-bearing walls that offer maximum
rigidity with the absence of flexible joint connections. The rigid members are able to
withstand bending moment, shear and axial loads.
Figure 4.7.4: Current rigid connections in the VIC:
Concrete wall to slab detail (Ching, 2014)
Figure 4.7.5: Example of a flexible joint: Pin
connection
(Boake & Hui, 2018)
Materiality of the Structural Members
The rigidity of a structural element of a given material is the product of the material's
Young's modulus and the element's second moment of area. In this section, the rigidity
of the material of the structural member would be discussed.
As mentioned in section 3.2.1 of this report, the material of the structural members in the
VIC is reinforced concrete. As a composite, the young’s modulus of reinforced concrete
used in the VIC would have to depend on the type of steel used as well. The Young’s
modulus for concrete is in the range of 30-50 GPa (Engineering ToolBox, 2003), which .
With a low Young’s modulus value, the rigidity of the concrete is high. The more rigid an
element the more load it will attract. (Structural Engineering Theory, 2018). The modulus
of elasticity of concrete is relatively constant at low stress levels but starts decreasing at
higher stress levels as matrix cracking develops (Structural Engineering Theory, 2018).
The low elasticity ensures that concrete will be rigid enough for the VIC to minimize
deflection, but also remain an acceptable small deflection or dynamic response under
loading to prevent cracking which may lead to structural failure.
34

Geometry of the VIC
Rigidity of the structure is dependent on the geometry. As seen in the shape of the VIC
from the south elevation, the top of the VIC is wider than the base. The space on the right is
cantilevered without adding base supports to increase the size of the base. This makes the
shape non-rigid. A horizontal force from the left might collapse the structure.
Figure 4.7.6: Geometry of the VIC (South Elevation)
Summary
The VIC has rigid joints and materials, but non-rigid geometry. Suggested
improvements would be to provide support for the cantilever (Section 5.6)
In overall, the VIC is rigid enough to withstand deflection.
35

4.8 Conclusion for Analysis - A Proposal For
Amendments
Structural Analysis Components for Amendment
4.1 Safety - Ramp
- Cantilever slab and roof
4.2 Feasibility - Walls (For ramp and Fin walls)
- Columns
- First floor slab
- Ramp
- Roof
4.3 Economy - Beams
- Columns
- Slab
- First floor walls
- Roof
4.4 Optimization -
4.5 Stability - walls
- Columns
- Beams
- Foundation system
4.6 Strength - Columns
- Ramp walls
4.7 Rigidity - Cantilever
36

5.1 Foundation
Existing problem
The existing structure does not have a foundation to sit on.. This causes the building to
be unstable as it sits on a soft bed of soil.
Proposed solution
Design and construct a foundation system that is able to bare the load of the structure
and keeping the structure stable and rigid.
Factors determining the type of foundation
Location of building - The geographic location of the structure is a deciding factor of the
type of foundation that will be used. The topography,climate and wind speeds at site are
some of the characteristics that has a huge impact towards the design of a building.
Loads from building - the amount of load that is transmitted from the building is important
in designing the foundation
Type of soil on site -Building foundations need to be on stable and strong soils. Soils range
in strength. Some soils are able to support a skyscraper, while other soils are not able to
support the weight of a human. If the soil under a building is not stable, the foundation of
the building could crack, sink, or worse–the building could fall!
Type of neighbouring structures -Deep foundations of buildings and their impact on
neighbouring buildings is one of the most important issues when planning a new facility.
Whereas, the analyses of the threats often come down only to a simplified evaluation of
the building subsidence and to comparing them with the limit value.
The purpose of a foundation is to hold up and hold together the structure above it.
Contrary to our everyday experience the ground is not quite still and in many cases not
totally solid. A house which is just plonked down on bare earth is more likely to be
cracked or damaged over time by natural forces. A properly-built foundation increases
the amount of abuse a house structure can take and remain safe for the people inside it.
39

PAD FOUNDATION
Pad foundations are designed to spread a concentrated force that is to be applied to a
bearing stratum. They therefore need to be sufficiently stiff to spread the force into the
soil such that the founding pressure does not exceed its permissible bearing stress. This
can be done by either making the pad sufficiently deep so that the force spreads out by
a predefined angle or with reinforcement. The angle is determined based on the
strength of the concrete and the bearing capacity of the soil. For unreinforced concrete.
Figure 5.1.0 pad
footing
Figure 5.1.1 Foundation plan
Figure 5.1.2 Existing ground floor plan
4000mm
400mm
900mm
The reinforced concrete foundation was
designed with steel rebars casted into them
.The level at which the pad foundation is to
be placed is also important, as to have it too
deep can result in difficult and even
dangerous conditions during construction.
40

Strip foundation
Strip foundations (or strip footings) are a type of shallow foundation that are used to
provide a continuous, level (or sometimes stepped) strip of support to a linear structure
such as a wall or closely-spaced rows of columns built centrally above them. It helps
spread the load evenly and reduces the pressure towards the ground..
Figure 5.1.3 Existing ground floor
plan
plan
plan
Feasibility: the construction of the foundation system would e the first stage of the
construction process. Excavation works have to be done followed by the placement of
the foundation components.
Stability and strength: The absence of the foundation system under the structure
would instantly result in a catastrophic disaster. The weight from the building would
unevenly compress the the soil that it sits on. The stability is of the building on uneven
soil would be unsafe its weight is unevenly distributed towards the soil.
41

5.2 Columns
Existing errors:
1. Column design does not allow seating for the beams to further support the first
floor structures.
2. The column system is not positioned evenly in a grid system, causing uneven load
distribution of slab above.
3. Curtain wall not sufficient to carry load of slab above.
Section 62 of the Uniform Building By-Laws Act 1984 stated that :
The reduction in assumed total imposed floor loads given in the Table 1 below may be
taken in designing column, piers, walls, their supports and foundations.
Table 1:
REDUCTION IN TOTAL DISTRIBUTED IMPOSED FLOOR LOADS
No. of floors, including the roof, carried
by member under consideration
Reduction in total distributed imposed
load on all floors carried by the member
under consideration (%)
1 0
2 10
3 20
4 30
5-10 40
Over 10 50
The columns of the VIC is responsible in holding the first floor and roof. Hence, 2 floors
in total. However the existing columns do not comply to the requirements (refer to
figure…). Therefore, proposed solution would focus on this aspect.
Consequences:
1. The lower ground will not be able to support the weight above and will collapse
2. The confusing layout would prolong the time of construction and hence, increases
total cost of construction
Columns are basically vertical members which span from substructure to
superstructure and play a crucial role in transfer of load from top of structure to
bottom footing (Gharpedia, n.d.).
42

- Grid lines were drawn to align with the first floor’s vertical louvered walls’ position so
that the columns above can be hidden in between the walls to keep the original
poetics and outlook of the building.
- Columns were added respectively on the intersections of the gridlines of the bottom 2
rows, including in between curtain walls)
- Refer to column plans and column schedules at the end of the columns section
Figure 5.2.2 Existing ground floor plan Figure 5.2.3 Amended ground floor plan with newly
introduced gridlines and column arrangement
2. Introduce a draft grid system
3. Introduce columns along the curtain walls
Proposed solution :
1. Introduce a new column design on ground floor
Height depends on
the position of column
below the ramp
300mm
300mm 300mm
300mm
6o
- Recesses were introduced into the columns to create a seating for the beams. Hence,
reducing the excessive amount of loads acting on the beams as more of it can be
transferred down to the columns through the recess.
- Refer to column schedule on pg… for column schedule.
Recess
Ramp
slab
Beam
Load distribution
Figure 5.2.1 New column designs for ground floor and first floor and how the loads are distributed
43

5. Rotate the columns on the first floor to fit into the fin walls
4. Erect columns all the way up to the roof slab
Figure 5.2.4 Existing perspective with
irregular column pattern
Figure 5.2.5 Amended perspective showing
erected columns and newly introduced
columns
- Columns C1A,D1A,C1B,D1B,C2,C2A,C2B,C2C,C3 and C4 (refer to column plan in
figure…) were erected to the roof slab meanwhile the rest are newly introduced
columns.
- This improves the distribution of load from the roof slab fairly downwards to the
ramp slab, ground floor then foundations through the evenly arranged columns.
Hence, reduces compression stress on the respective columns and therefore
able to support more dead and live load.
- Columns C2,D2,C2A,D2A,C2B,D2B,C2C and D2C (refer to column plan in figure..)
are rotated to hide themselves in between the fin walls. Hence, a clean finish
can be produced.
Figure 5.2.6 Orientation of amended first floor columns showing on plan
and a blown up perspective
44

Figure 5.3.7 Ground floor column plan
Figure 5.3.8 First floor column plan
45

ColumnSchedule
Table5.1ColumnSchedule
46

Structural analysis
Feasibility
The grid layout allows even placement of columns throughout the foyer where there are
lacking structural walls. With this improvement, It creates great convenience for the labours in
drawings to hands-on construction work.
Economy
The tidy and clear column layout according to grids would not cause unnecessary complication
and mistakes during construction that would potentially add on to the total project cost.
Stability
The increase in amount of columns and also recesses introduced into ground floor columns
significantly helped in transmitting a larger amount of load back down into the foundations.
With more loads being able to distribute itself, the more stable the building is.
Strength
The columns itself is already reinforced concrete which generally benefits in strength, with the
modified design of the columns, more reinforcements are added into the structure. Hence, the
building have increased in its overall strength.
47

Primary beams
Secondary beam
The main beams which transfers the load
from secondary beams or slabs to columns
are called primary beams.
The beams which are constructed to
transfer the load of slab on main /
primary beams are called secondary
beams
A beam is a structural element that primarily resists loads applied laterally to the beam's
axis. Its mode of deflection is primarily by bending. The loads applied to the beam result in
reaction forces at the beam's support points. The total effect of all the forces acting on the
beam is to produce shear forces and bending moments within the beam, that in turn
induce internal stresses, strains and deflections of the beam. Beams are characterized by
their manner of support, profile (shape of cross-section), length, and their material.
Figure 5.3.1 Amended beams
Figure 5.3.2 Amended beams
A.i
A.ii
B
C
Existing problem
The existing building does not have a proper beam system them followed the grid
structure. The columns alone will not be able to bare the load of the slabs.
Proposed solution
To design and construct a beam system that would fit the grid structure of the columns
BEAM DIMENSIONS(L,W,H)mm CONNECTION TYPE
A.I 1200x300x400 Suspended Beam to slab
A.II 4000,300,400 Suspended Beam to slab
B 4000,250,250 Beam to slab
C 5700,250,250 Beam to column
D 5700,250,250 Beam to roof
5.3 Beam
48

Among beams to column connection, loaded beam columns are very vital for creating
superior structural design. The stability analysis of the elastic-plastic framed structure
depends on the solution of loaded beam columns toward any structure.
Reinforced concrete beam to column construction
details
1st floor
column
column
Slab and beam
Figure 5.3.3 beam to column
construction detail
construction detailFigure 5.3.5 beam to column
construction detail
The primary beams are casted under the floor
slab and roof slab. The slab is then placed onto
the column.
The secondary beams are casted together
with the columns on both sides.
Figure 5.3..4 location of beams
Direction of load
transfer
49

Reinforced concrete beam to floor slab construction details
Edge beam
Steel rebar
Figure 5.3.7 beam to floor slab
construction details.
wall
indooroutdoor
Figure 5.3.8 location of
beams
The beams under the floor slab are
responsible for transferring the load
from the edges of the slab to the
middle of it where it is then transferred
to the foundation by the existing load
bearing walls Figure 5.3.9 direction of
load transfer of beams
Figure 5.3.11 beam to floor slab
Reinforced concrete beam to 1st floor columns construction
details
50

Structural Analysis
Feasibility : the overall structure of the vic follows a grid system. The beams are
Strength & stability: The beam system is a great way to transfer horizontal loads to
vertical loads. This would increase the rigidity of the structure, making it less flacid and
less likely to move .It also gives a stable base for the ramps to sit on. The beams would
also improve the overall strength and stability of the slab and entire structure.
Safety: The ammendment made is a nesecery desicion made to mantain the the overall
safety of the structure. The skeletal structure act as the bones of the building, protecting
and mantaining its form.
51

5.4 Walls
5.4.1 Ground Floor Walls
Existing errors
1. The single layer non-load bearing masonry walls are not sufficient to carry the
loads to support the upper level.
2. Hand laid brick process contributes to the increase in labour cost and the
production of bricks itself further increases the processing cost.
3. Brick walls are also prone to be damaged from moisture, considering the VIC is in a
tropical climate zone, it’ll worsen the moisture effect.
Consequences
1. The insufficient strength of these non-load bearing walls will deflect and cause the
structure to crumble.
2. The moisture damage in long term causes the masonry walls to lose its strength
even further. Hence, its both structurally impractical and economically inefficient.
Figure 5.4.1 Diagram showing structural overload causing
deflection of single layer masonry wall
52

Reinforcement
bars
Post-modification:
Concrete
Proposed solution
1. Change the masonry walls into reinforced concrete wall
Single layer masonry wall
Figure 5.4.2 Existing ground floor plan
with highlighted location of masonry walls
100mm thick
Figure 5.4.3Proposed Reinforced
concrete diagram
- Reinforced concrete provides
the much needed structural
support as well as the
materiality poetics the VIC is
heading for.
- Reinforced concrete walls are
also much faster to be
constructed ( in the case of this
proposed modification, cast
in-situ), together with the
formwork. Additionally, cement,
water, aggregates and rebars
are cheaper.
- Concrete walls are relatively
easier to maintain in long terms
compared to masonry walls
because of it flexible pre-form.
53

Structural analysis
Feasibility
The cast in-situ method of construction is easy to understand and also to build. The materials
used to construct reinforced concrete walls are also easy to find. Hence, creates an overall
convenience for during the transportation and construction process
Strength
Reinforced concrete itself is well-known for its ability to withstand huge amount of forces and
loads. Therefore, the strength of the walls would be relatively higher compared to before.
54

5.4.2 Fin Walls (First Floor)
Figure 5.4.2.1: First Floor walls
indication on first floor plan
Figure 5.4.2.2: First Floor walls indication on
Axonometric View
2. Calculations
1. Existing errors
The main issue with the fin walls is that the materiality of the load bearing walls are all
reinforced concrete, which imposes high amounts of dead load onto the supporting members
below.
As the North and South rows of walls are similar, the self-weight for N1-N11 will be
multiplied by 2 to obtain the total self-weight of the customized walls.
Density of Reinforced Concrete: 24 kN/m3
Self-weight: Dimension x Density of reinforced concrete
Initial Total self-weight of fin walls: 791.232 kN/m3
55

3. Proposed solution:
The materiality of the load bearing walls are changed into single layer brick masonry walls
to reduce the load imposed on supporting members below. The modification of adding
columns to support the roof enables the fin walls to become non-load bearing walls as the
load will be transferred down the columns instead.
4. Calculations:
Density of brickwork: 19kN/m3
Figure 5.4.2.3 :: Reinforced
Concrete wall
Figure 5.4.2.4 Brick masonry wall construction
Initial Total self-weight of light masonry fin walls:626.386 kN/m3
The self-weight of the fin walls have been reduced by 164.846kN/m3, thus reducing the
dead load imposed on structural members beneath.
56

Structural Analysis
Feasibility and Economy: The change made from load-bearing walls to light masonry has
reduced the cost of construction and material, by reducing the amount of materials
required plus the the costs of having formwork for reinforced concrete construction. Thus,
the modification is more economical and feasible,
Strength: The change from load-bearing reinforced concrete walls to non-load bearing
light masonry walls does not mean the strength of the structural members of the VIC is
reduced as the strength is transferred onto the modified columns. Columns offer a greater
option of withstanding external loads like compressive, tensile, torsion, shear and also
moment, making them superior than load-bearing walls.
Stability: The reduction of dead load by the reinforced concrete fin walls will improve the
stability of the structure.
Safety: By reducing the possibility of imposing too much dead load on the structural
members below, the possibility of catastrophic structural collapse is reduced, thus
improving the safety of occupants in the building.
57

5.5 First Floor Slab
Column Height from ground floor to floor beam (mm)
C1A & D1A 2300
C1B & D1B 2500
C2 & D2 2700
C2A & D2A 2900
C2B & D2B 3100
C2C & D2C 3300
C3 & D3 3500
The ramp is a unibody 24000 mm long in-situ slab inclined upwards with an angle of 6
degrees from 1st floor to 2nd floor. The riser of ramp is 1250mm.
Existing Errors:
It is not possible for a concrete flat slab to span up to 24000 mm, which connects 1st
floor to 2nd floor sits directly onto the columns without the support of beams or joists.
Consequences :
Load will not be distributed evenly. Beams which are structural elements that transfer
and resist loads applied laterally to the beam’s axis then vertically downwards to the
columns at the ends of beams.
Proposed solution :
The two-way in-situ reinforced concrete slab is supported on 4 sides of beams,
The bay is close to a square with the width and length of asa hence load from above
could be distributed in 2 ways to the closest beams and columns . Distribution bars are
provided at both the ends in two way slab to resist the formation of stresses.
Reinforced concrete slab thickness : 300mm
Reinforced concrete slab length from A to B : 24000 (ramp start to balcony)
Figure 5.5..1 - Before amendments - Missing beams below floor
slab
C1A & D1a
C2C & D2C
58

Figure 5.5..2:
Proposal - Instead of a flat slab resting directly on columns,
we propose to have a two-way slab with tie beams.
Figure 5.5.3 -
Amended two-way in situ-concrete slab with the incline of 6 degrees upwards.
Bay
Room for columns to be slided into
59

5.6 Cantilever
Existing errors:
Consequences:
1. The cantilever slab will not be able to support the loads acted upon it to sustain in
its position.
2. The cantilever slab is considered to be connected to a ‘loose joint’ and would
snap, causing threats to the users in the VIC
32 m2
4000
8000
1. The 4000mm cantilever span is far too heavy to withstand the moment forces
considering that the existing cantilever has an obvious fracture point and
insufficient backspan
Cantilevers are usually limited to a span of about 25 to 35% of the back span and
should be supported by a stiff support such as beam or column. The deflection of a
cantilever is sensitive to the rotation at the support. In particular, a long cantilever with
a short back span may deflect down significantly or a short cantilever with a long back
span may deflect up significantly (C&CAA, 2003)
Backspan
Fracture
point
Cantilever
floor slab
Figure 5.6.1 Existing dimensions of the
cantilever floor slab
Figure 5.6.2 Back span, fracture point and
cantilever floor slab indications
60

Proposed solution:
C3 / D3 ground floor
columns
C3 / D3 first floor columns
1. Apply load on the connected end of the cantilever slab
Load transferred through
columns C3 and D3
Direction of forces that
creates the uplift
Potential loads
- The meeting point / fracture point between the ramp slab and cantilever slab
is shifted to locate below the midpoint of columns C3 and D3.
- The loads from the upper levels that are transferring through the columns
will stapler on the fracture point, joining both the slabs together. This reduces
the moment forces (forces that causes deflection) acting at the outer edge of
the cantilever slab.
- Due to the cantilever slab being connected firmly to the ramp slab, the ramp
slab acts as the back span of the cantilever. The slight slope of the back span
gravitates the loads from the cantilever towards itself. Hence, an uplift force
is created at the outer end of of the cantilever slab.
- Considering the 4000mm span of the cantilever, the uplift force would not be
too extreme with the potential loads acting against it.
Figure 5.6.3 Amended first floor plan further showing the load distribution of the
newly introduced modification
61

2. Introduce beams and trusses to further support the cantilever slab
The recess introduced to the columns are
plus points to also act as a truss support for
the cantilever beams. This is because it
increases the span of the cantilever sitting
on a flat surface and also helps in
transferring more portions of the loads
from the cantilever slab down the columns.
Beams are essential support
for the cantilever slab
together with the columns. It
allows the slab to sit and
allows a direction for the
loads to be transferred, in
this case, the cantilever slab
acts as an one-way.
Structural analysis
Safety
The proposed modification for the cantilever floor slab creates support. The support is sufficient
to allow live loads to add on together wit the existing dead loads and therefore it is safe for the
occupants to move around the cantilever floor slab area.
Figure 5.6.4 Indication of beam and truss
from elevation
Figure 5.6.5 Indication of beams and
two-way slab on cut out of first floor plan
62

5.7 Roof slab
Existing Errors:
1. The long roof slabs which connected to 1st floor is supported by load bearing walls
which id the fin walls . The roof slabs sits directly onto the the walls without the
support of beams or joists hence the distribution of load will not be effectively
distributed.
2. The thickness of the roof slabs is too thick for the overall frame structure of the
building.
Consequences :
1. Load will not be distributed evenly. Beams which are structural elements that transfer
and resist loads applied laterally to the beam’s axis then vertically downwards to the
columns at the ends of beams.
2. Roof slab may collapse/break at weak points where its furthest from columns,
Proposed solution :
1. The one way in-situ reinforced concrete roof slab with beams
2. Existing columns are erected towards the roof slabs.
3. Reduce the thickness of the roof slab
Reinforced concrete roof slab thickness : 250 mm
Figure 5.7.1 : [ south section ] absence of beams supporting the roof slab with the thickness of
300mm
Figure 5.7.2 : [ south section ] amended roof slabs with beam with the thickness of 200mm.
Concrete roof slabs
beam
63

Structural Analysis
Economy
The construction of the roof slabs with beams is a simpler system which results in cheaper
ratings that satisfies both the economics and sufficient load support that should be
considered.
Feasibility
Roof slab is maintained as a reinforced concrete slab but is made thinner hence lighter
without having to compromise its structural integrity. Apart from that, due to the lack of
structural support, one way beams are integrated on the slabs. Hence, the design of the
roof slabs with beams can be physically constructed through convenient and practical
way possible.
Strength & Stability
The strength and stability of the roof slab is improved by integrating one way beams and
reducing the thickness of the slabs. The structure is simpler as the dead load that the
columns and beams carry is only the concrete roof slabs. Therefore, the amended roof
slabs with beams is stable and strong in structure wise.
64

5.8 Eggcrate
Extended beam
Existing errors:
1. The eggcrates structures with the height of 8 metres are standing on its own without any
supporting system.
2. The eggcrates have no specific connection that anchored them to the ground
Consequences:
1. The eggcrate will not be able to support the weight by itself and will collapse
Proposed solution :
1. Extend the beam from level 1 and roof towards the eggcrates
2. Reduce the distance of the eggcrates to the building
3. Strip foundation is placed to support the eggcrates structure
Distance of eggcrate to the building: 800/750 mm
Figure 5.8.2. Beams connected to the eggcrate structure
Figure 5.8.1. Existing position of eggcrate shading ,
2000 mm away from the building
figure 5.8.2.1 : base plate connected to
the beam and eggcrate
65

Figure 5.8.3. Amended plan of the eggcrate structure
Figure 5.8.4. Amended elevation with eggcrate
foundation pad
Figure 5.8.5. 1.(Construction of Steel
Frame Structure..& floors , n.d.)
Feasibility
The eggcrates materiality is maintained as a metal . Besides, due to the lack of structural
support, beams from the first floor is extended towards the eggcrates. This design of the
eggcrates structure anchored to the beams can be physically constructed through
convenient and practical way possible.
Strength & Stability
The strength and stability is improved by connecting the beam to the eggcrates. This will
avoid the eggcrates from toppling down.
66

7.0 Load Distribution
After proposed amendments based on the structural analysis of the structure of the VIC,
the load-distribution has vastly improved with a more organised load path to enable the
structural members to withstand the distributed load more evenly and efficiently.
Figure 7.2: Load distribution diagram in Axonometric View after amendments (With removed first floor
slab and roof slab to expose the skeletal structure)
Figure 7.1: Load distribution diagram in Section View before amendments
Load path (Before Amendments)
Roof → Columns
→ Ground
Roof → Non-load bearing walls
→ Load bearing walls
Roof → Beams →
Columns →
Foundation → Ground
Roof → Load bearing walls →
Load bearing walls
Load path (After
Amendments)
67

8.0 Conclusion
Structural analysis of Safety. Feasibility. Economy, Optimization. Integration, Stability,
Strength and rigidity highlighted the problem areas of the Visitor Interpretive Centre for
proposal of amendments. The problems highlighted and amended are:
1. The addition of a pad foundation
2. Supplying a grid and organising the columns, and extending the columns up
towards the roof for support
3. The addition for two-way beam system for the first floor and a one-way beam
system for the roof
4. Altering the walls on the ground floor around the ramp from non-load bearing
single layer masonry walls to load-bearing reinforced concrete walls
5. Changing the load-bearing fin walls on the first floor to light masonry walls
6. Addition of beams for the cantilevered first floor slab and roof slab for load
distribution
7. Reducing the thickness for the roof slab
8. Reducing the distance between the egg crate and supplying intermediate beams
for support
All of the above were discussed with reference to the structural analysis done in the
before sections. Adequate research and references from the Malaysia’s Uniform Building
By Law (UBBL 1984) have aided in completing the report based on factual knowledge.
68

List of figures
Figure Page
Figure 1.2 : the facade of the building 3
Figure 1.3 : 1st floor plan of the building to
showcasing the fins .
3
Figure 1.4: ground plan of the VIC 4
Figure 1.5: first floor of the VIC 4
Figure 1.6 : Front elevation 5
Figure 1.7: North elevation 5
Figure 1.8: West elevation 5
Figure 1.9 : East elevation 5
Figure 3.1.1: Load-bearing walls and columns on
the ground floor
7
Figure 3.1.2: Load-bearing walls on the first floor 7
Figure 3.1.3: Example of the load-bearing
structured building (The Constructor, n.d.)
7
Figure 3.1.4: Example of a framed structure
building (Civil Digital, n.d.)
7
Figure 3.1.5: Load-bearing walls in north
elevation view
8
Figure 3.1.6: Columns extending up to the first
floor slab (South Elevation: Steel louvres and
Curtain wall removed)
8
Figure 3.2.1: Concrete pouring process in the
construction of reinforced concrete (R Bray
Groundworks. n.d.)
11
Figure 4.1 13
Figure 4.2 13
Figure 4.3.0 14
Figure 4.3.1 14

List of figures
Figure Page
Figure 4.2.0 Ground Floor Plan 16
Figure 4.2.1 First Floor Plan 16
Figure 4.2.2 Elevation Drawing 16
Figure 4.2.3 17
Figure 4.2.4 17
Figure 4.2.5 First floor 18
Figure 4.2.6 19
Figure 4.2.7 Ground Floor Concrete Slab 20
Figure 4.2.8 First Floor COncrete Slab 20
Figure 4.2.9 First Floor Plan 21
Figure 4.3.0 Section 21
Figure 4.3.1 Section 22
Figure 4.3.1 Irregular Column Arrangement 24
Figure 4.3.2 Difference in height of vertical
louvered walls
24
Figure 4.3.3 Standard Rectilinear Form 24
Figure 4.5.1: Types of Load Imposed (South
Elevation with Louvres removed)
27
Figure 4.5.2 28
Figure 4.6.1: [ section from east ] the current load
distribution without beam
29
Figure 4.6.2 : flat slab without beams 29
Figure 4.6.3: [ section from south ] the current
load distribution without beam with irregular
placement of columns.
29

List of figures
Figure Page
Figure 4.6.4: ramp that leads to first floor of the
building.
30
Figure 4.6.5 : [ east section ] structure of the ramp
leads to first floor.
30
Figure 4.6.6 : diagrams of internal force acting on a
concrete structure (Design and Control of Concrete
Mixtures, n.d.)
31
Figure 4.6.7 : [ south section ] bending of the floor
slab with combination of tension and compression
forces in the VIC building.
31
Figure 4.6.8 : diagrams on relation between cement
ratio and strength of concrete
32
Figure 4.7.1: Forces acting to deform a polygonal
shape structure (“Rigidity”,n.d.)
33
Figure 4.7.2: Added bracing to increase rigidity which
resists deformation (“Rigidity”, n.d.)
33
Figure 4.7.3: Different buildings respond differently
to the same ground vibration
(Murty, n.d.)
33
Figure 4.7.4: Current rigid connections in the VIC:
Concrete wall to slab detail (Ching, 2014)
34
Figure 4.7.5: Example of a flexible joint: Pin
connection
(Boake & Hui, 2018)
34
Figure 4.7.6: Geometry of the VIC (South Elevation) 35
Figure 5.1.0 pad footing 40
Figure 5.1.1 Foundation plan 40
Figure 5.1.2 Existing ground floor plan 40

List of figures
Figure Page
Figure 5.2.1 New column designs for ground floor
and first floor and how the loads are distributed
43
Figure 5.2.3 Amended ground floor plan with newly
introduced gridlines and column arrangement
43
Figure 5.2.4 Existing perspective with irregular
column pattern
44
Figure 5.2.5 Amended perspective showing erected
columns and newly introduced columns
44
Figure 5.2.6 Orientation of amended first floor
columns showing on plan and a blown up
perspective
44
Figure 5.3.7 Ground floor column plan 45
Figure 5.3.8 First floor column plan 45
Figure 5.3.1 Amended beams 48
Figure 5.3.2 Amended beams 48
Figure 5.3.3 beam to column construction detail 49
Figure 5.3..4 location of beams 49
Figure 5.3.7 beam to floor slab construction details. 50
Figure 5.3.8 location of beams 50
Figure 5.3.9 direction of load transfer of beams 50
Figure 5.3.10 beam to column construction details. 50
Figure 5.3.11 beam to floor slab construction details. 50

List of figures
Figure Page
Figure 5.4.1 Diagram showing structural
overload causing deflection of single layer
masonry wall
52
Figure 5.4.2 Existing ground floor plan with
highlighted location of masonry walls
53
Figure 5.4.3 Proposed Reinforced concrete
diagram
53
Figure 5.4.2.1: First Floor walls indication on first
floor plan
55
Figure 5.4.2.2: First Floor walls indication on
Axonometric View
55
Figure 5.4.2.3 :: Reinforced Concrete wall 56
Figure 5.4.2.4 Brick masonry wall construction 56
Figure 5.5..1: Before amendments - Missing
beams below floor slab
58
Figure 5.5..2:
Proposal - Instead of a flat slab resting directly
on columns,
59
Figure 5.5.3: Amended two-way in situ-concrete
slab with the incline of 6 degrees upwards.
59
Figure 5.6.1 Existing dimensions of the cantilever
floor slab
60
Figure 5.6.2 Back span, fracture point and
cantilever floor slab indications
60
Figure 5.6.3 Amended first floor plan further
showing the load distribution of the newly
introduced modification
61
Figure 5.6.4 Indication of beam and truss from
elevation
62
Figure 5.6.5 Indication of beams and two-way
slab on cut out of first floor plan
62

List of figures
Figure Page
Figure 5.7.1 : [ south section ] absence of beams
supporting the roof slab with the thickness of
300mm
63
Figure 5.7.2 : [ south section ] amended roof
slabs with beam with the thickness of 200mm.
63
Figure 5.8.1. Existing position of eggcrate
shading , 2000 mm away from the building
65
Figure 5.8.2. Beams connected to the eggcrate
structure
65
figure 5.8.2.1 : base plate connected to the
beam and eggcrate
65
Figure 5.8.3. Amended plan of the eggcrate
structure
66
Figure 5.8.4. Amended elevation with eggcrate
foundation pad
66
Figure 5.8.5. 1.(Construction of Steel Frame
Structure..& floors , n.d.)
66
Figure 7.1: Load distribution diagram in Section
View before amendments
67
Figure 7.2: Load distribution diagram in
Axonometric View after amendments (With
removed first floor slab and roof slab to expose
the skeletal structure)
67

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