Mechanical and Electrical Assessment of Materials for Building a Football Stadium for Qatar 2022 World Cup

This presentation discusses the mechanical and electrical assessment of materials for building a football stadium for Qatar 2022 World Cup. It covers the concept design of the stadium, construction material, electric power and components installation, RLC circuit calculation, and more. Suitable concrete material is chosen based on partial destructive or non-destructive tests. Renewable energy system is installed to produce enough power. The RLC circuit calculation is done based on the given data by applying circuit theory principles.

ENGINEERING SCIENCE PART 2
Name of the Student
Name of the University
Author Note

Introduction:
The objective of this assignment is to build a football stadium for the Qatar 2022 world cup the
mechanical and electrical assessment of materials that are needed to be used are described in details
and the calculations of the strength and quantity of materials and electrical components are done that
will ensure stability for long time and safety of people inside the stadium. The constructional
components of the stadium such as the various load bearing materials, the types of concrete that can
be used are hypothesized and the breaking points of those are represented to select the most suitable
and safe items for the construction.

Concept Design of Stadium:
• Pre-concept design: Collecting data from different sources to do the analysis of the chosen site and the
confirmation of the requirements.
• Concept design: Developing the details of the design for determining the required construction materials and the
extra structures that are needed.
• Schematic design: The design of the whole stadium including major structures, gates and electrical components
using a software like AutoCAD or else.
• Calculation and development: Calculating the mechanical and electrical specifications of the different structures
and components and then choosing the best fitted equipment for the design.
• Date issue: Issuing a date for starting the real construction of the stadium. Selection of well experienced tender
before date of issue is recommended to ensure no delay in the date of issue.

Task 1a:
Now, to construct a stadium it may take from approximately 18 months to 3 years depending on the
size of stadium, climate condition and unexpected events while ongoing construction process. The
generalized way of starting the construction is to construct a seating bowl through site excavation that
can be of 50 feet deep or more. Then the masonry work is performed with manufacturing the
components and installing them in planned places. After the initial phase the lights are installed,
concession areas, restrooms, locker room, portable toilets are installed. As the football stadium is
prepared for the world cup, hence there should be enough green grass in the field for players’ comfort
and improved playing condition. Now, as natural grass requires suitable soil conditions to grow which
may not available in chosen site, installing artificial grass can solve the problem at a lower cost and
minimized injury of players.

Schematic diagram of the stadium:

Construction Material:
Now, the most important phase of construction is to choose the concrete material for building the
structures. The general composition of any concrete is cement, coarse aggregate (like screening and
gravel), fine aggregate, chemical and water. The percentage of the different composition of concrete
are 7 to 17% of cement, 15 to 20% of water, 63 to 78% of aggregate and 22 to 37% paste (mixture of
cement and water).
Table: Proportions of 20 mm mix cement for different strengths
Strength Cement proportion Sand proportion Water and cement Ratio
15 MPa 1 2.5 0.6
20 MPa 1 2 0.55
25 MPa 1 2 0.5

Cement types:
The cement which is an essential component of the concrete can be of three types which are Portland
cement, blended cements, and colour cements. Now, Portland cements are used more generally to
form most of the structures (www-pub.iaea.org 2018). They can be of three types: High early
strength cement, Low heat cements and sulphate resisting cement. Now, as the stadium needs to be
completed early hence it is recommended to use the high early strength cements in most of the
position and in the guest seats and club house seats, low heat cements can be used to protect the seats
from heat during summer. Blended cements gain strength slowly and hence not recommended to use
in the stadium structures.

States of Concrete:
Now, addition of different chemicals with the cements make two stages of concretes which are
Plastic-state concrete and the hardened concrete. The two features of plastic-state concrete are
workability and cohesiveness. Workability of the plastic state concrete is high as this can be easily
handled while working and the cohesiveness of the concrete is the property which holds the
concrete after making the structure with it (www-pub.iaea.org 2018). The hardened concrete has
the two features durability and strength. It is highly durable as it can last long with no wear and tear
in extreme climate conditions and concrete at the hardened state has great strength. Increasing the
content cement and reducing the water content builds durability and strength and hence it is
recommended to use concretes with high amount of cement proportion.

Destructive and Non-destructive Methods:
Now, to judge the strength of the concrete and its breaking stress several Non-destructive and partial
destructive methods can be applied to get the quality of the concrete. The non-destructive quality tests are
slump test, compression tests (Gholizadeh 2016). The slump test tests the workability of the concrete while
the compression test judges the strength of the concrete in standardized condition (www-pub.iaea.org 2018).
The partial destructive tests that can be employed are Pull-out test, Pull-off test, Core test. The pull-out test
can be of two types 1) Danish Lok Test: A head is emerged into the concrete when it is in use. The test gives
a good indication of the compressive strength of the concrete. 2) BRE pull-out test: In this test a hole is
drilled inside the concrete structure and then a fixed object is pushed into it and then pulled out. This test
does not require the head to be casted in the structure of concrete, but it measures the tensile strength by
some calibration standard it is then converted into the compressive strength by some calibration standards.

Pull-Out test schematic:

Flexure test:
In case of flexure test the theoretical maximum stress that can occur in the bottom fibre of the beam
which is known as modulus of rupture is calculated. In the calculation it is assumed that the stress is
directly proportional to the distance between the acing point and the neutral axis. Thus, the
estimation of the modulus of rupture will always be greater than the tensile strength and it depends
on the dimension of the beam.

The modulus of Rupture of different sized beams:

Linear relationship between the Modulus of Rupture and Tensile
Strength:

Chemical test:
Beside these tests the chemical test which determines the chemical composition of the concrete
structure is useful to have an idea about the condition of the concrete, durability and how suitable it
is for continuous use. The ratio of splitting strength to compressive strength with respect to
compressive strength is shown for different composition chemicals and for different countries
Denmark, Brazil, Japan and US(Gravel).

Relationship between Ratio and Compressive strength for different
chemicals:

Choosing the right material:
Now, for choosing the right concrete for building the stadium the above one or more partial
destructive or non-destructive tests can be performed. The concrete chosen should be enough
sustainable, durable and cohesive to hold the structures of the stadium uncracked for at least 15 to 20
years. Hence, by the above results and graphs obtained previously in the published articles it is
assumed that the concrete with high early strength cement will be suitable one for building the
stadium.

Electric power and components installation:
The electric power requirement in the stadium is huge as enough power should be
uniformly distributed in the 8 light-stands and power to guesthouse, clubhouse, Big Screen
Tv in the field, lights in the pantry. Apart from that a renewable energy system must be
installed that will produce enough power to fully light-up at least 4 light-stands and the
guest and clubhouse. As obtained from the previous articles it is expected that
approximately 1180 solar panels producing 400 kW of power would be enough to meet
the above conditions (López and Frontini 2014). The energy efficient LED lights need to
be installed in all the light-stands and in other areas to reduce the costing of the electricity.

Task 1b:
a) The values of the network components of the circuit given by the stadium committee are
B1 = 14 Volts, B2 = 18 Volts, R1 = 7 Ω, R2 = 5 Ω and R3 = 2Ω.
Now, using the superposition theorem considering only the B1 = 14 V active and B2= 0 V(short-
circuited) (Naderian, Arani and Gharehpetian 2017).
IR1 = B1/(R1 + R2*R3/(R2+R3)) = 14/(7 + (5*2)/(5+2)) = 14/(7+10/7) = -1.66 Amps.
IR2 = (IR1*IR3)/(IR2+IR3) = (1.66*2)/(5+2) = -0.47 Amps.
So, IR3 = -1.66 + 0.47 = -1.19 Amps.
Now, short-circuiting B1 and considering B2=18 Volts active
IR3 = 18/(2 + (7*5/(7+5))) = 18/(2 + 35/12) = 18/4.92 = 3.66 Amps.
Now, IR1 = (3.66*5)/(5+7) = 1.53 Amps.
IR2 = 3.66-1.53 = 2.13 Amps.
So, the net currents are
IR1 = 1.53 – 1.66 = -0.13 Amps.
IR2 = 2.13 – 0.47 = 1.66 Amps.
IR3 = 3.66 – 1.19 = 2.47 Amps.

b) Now applying Thevenin’s theorem
R2 = RL (load resistor) then
Pulling out R2 and then applying KVL
B1 = I(R1+R3) + B2 => 14 = I(7+2) + 18 => I = -4/9 Amps.
So, Vth = VR3 + B2 => Vth = -4/9*(2) – 18 = -18 – 8/9 = -18.89 volts.
Now, Shorting every voltages Rth = (R1*R3)/(R1+ R3) = (7*2)/(7+2) = 14/9 =1.55 Ω
Now, connecting the RL in series with Rth supplied from Vth the current (Tawi and Ahmad 2017)
IL = IR2 = -18.89/(1.55 + 5) = -2.88 Amps.

Inductance and its application:
In the iron core inductors and switching transformers the inductance is large and the resistance is low
and hence the current through the inductor lags the voltage across it. In ideal cases the current lags
the voltage by 90°. A typical waveform in an inductor for AC supplied sinusoidal voltage is shown
below.

Electromagnetic induction principle and application:
The main principle of electromagnetic induction is given by Faraday’s law which states that the
changes in magnetic field around a closed circuit induces an emf (electromotive force) in the circuit.
In addition, the Lenz’s law states that the direction of the current induced will be such that it opposes
the direction of magnetic flux range that producing it. These two principals are applied in electric
motors, transformers and many electric instruments involving inductive coil.

RLC Circuit calculation:
The provided RLC series circuit by the stadium committee is given
below.

RLC circuit calculation:
The values of components and frequency are
R = 14 Ω, L = 0.5 H, C = 100 μF, Vs = 10sin(wt), f = 50 Hz.
Hence, XL = jwL = j2*π*50*0.5 = j157.08 Ω.
XC = 1/j*w*C = -j/(2*π*50*100*10^(-6)) = -j10^(6)/(2*π*50*100) = -j31.82 Ω.
Hence, Z = R+ jwL+ 1/j*w*C = 14 + j157.08 -j31.82 = 14+ j125.26
Now, the max current Im = Vm/Z = 10/(sqrt(14^2 + 125.26^2)) = 0.079 Amps.

Conclusion:
Hence, in this assignment the mechanical and electrical components of the football stadium design is
properly addressed from different publishes journals and research papers and from there based on the
requirement of the stadium appropriate material and electrical components are chosen. Furthermore,
design circuit of the stadium and its components are accurately found based on the given data by
applying circuit theory principles.

Bibliography:
Www-pub.iaea.org. (2018). [online] Available at: https://www-pub.iaea.org/mtcd/publications/pdf/tcs-17_web.pdf
[Accessed 18 Sep. 2018].
Tawi, F.M.T. and Ahmad, N.H., 2017. Basic Calculation for DC Electrical Circuit.
Niu, H., Wu, Y. and Tan, D., 2016. Design and Analog Circuit Implementation of a Dynamic Feedback Control System
Based on RLC Series Circuit.
López, C.S.P. and Frontini, F., 2014. Energy efficiency and renewable solar energy integration in heritage historic buildings.
Energy Procedia, 48, pp.1493-1502.
Gholizadeh, S., 2016. A review of non-destructive testing methods of composite materials. Procedia Structural Integrity, 1,
pp.50-57.
Naderian, H., Arani, A.K. and Gharehpetian, G.B., 2017, December. A new control method based on droop and Thevenin
theorem to improve responses of VSIs in islanded MG. In Smart Grid Conference (SGC), 2017 (pp. 1-5). IEEE.

Thank You