Best thing about civil engineering

Recently i read a post somewhere in computer coding forum by some computer engineer. It read as follows:


".....


a = 5


b = 10


a = b

print a

You look at the code above and aren't sure what number gets printed out at the end

Alternative careers

Electrician


Plumber


Architect


Civil engineer


..........."

This is purely under estimated comment.Stupid people like him is creating some stupid softwares without puting his brain on use or knowing what the equation means in real life. And still they think they are really smart.

Lets see where he will not find a civil engineer or an architect..

the house he lives is designed by the architect and enforced by civil engineer .


the water he drinks will come from a soruce far away using system of channels, pipes, crossings..civil engnieer is supposed to get him that water even in draught!


the electriciy which he utilizes comes from the dam built by civil engineer and transmission line errected by civil engineers..


the road and bridges which he uses to go his home and office is built by civil engineers


the airport which he uses to fly his plane is built by civil engineers


the waste he generates in his lifetime is dispossed in secure way by civil engineers


the food he eats gets nutured from the water diverted by a civil engineer.

By copying and pasting the code you can easily be a computer engineer. F*** off. We know how to do our works.


Do you know how computers are used by civil engineer to put stupid people like you in comfort?

They use it to design the nuclear plant.


They use it to make dams and bridges.


They use it to design your gas pipes.


They use it to get answer of those things which you will never understand..


They use it to design the factories where your clothes are woven ..( wont you be shameful!)

I am and will be a civil engineer.

And if still you think you are clearver,

Do you know how high is your street light?


Do you know how many seconds red light glows in zebra crossing?


Do you know why your house do not break even by earthquake?

......


spread love not hate..

Indian Standard Steel Table

The collection of all the steel sections used in structural design of steel structure is given here. Download the excel data file. It contains Excel file containing all the steel sections used in Indian standard (IS). It will be very useful to all the steel designers.

Angle section	Tube section
Channel section	I section
Pipe section

Civil structures Ghunsa microhydro project (GMP).

The microhydro plant consists essentially of the all the components that a bigger hydropower plant will consist of. This article will try to give real impression of what micro hydro plant will look like in the field after construction.Ghunsa microhydro project has been used in this article. This project is located at an elevation of 3500m above sea level at Taplejung district of Nepal. The plant generates 35Kw.

Intake, gravel trap and settling basin.

Intake consists of a chamber to collect water. A gravel trap is generally provided to exclude coarse sediment to enter the water way. If water has sediments that need to be addressed, then a settling basin is also provided. The inake of GMP is at the right bank of Yamatari river. The water gets frozen in winter season. Settling basin has not been provided in this project as the water qualtiy is good.

Intake stucture	River protection for intake
Intake gate	Gravel trap flushing
Trashrack at intake	Gravel trap after the intake

Waterways

The waterways consists of canal joining intake and forebay. Depending upon the topography, the canal is in filling or cutting as shown in the figures.

Canal in cutting	Canal in filling. (Notice seepage!)
Canal in cutting

Forebay

Forebay is a water tank to hold water for specific time. The water from forebay is then tranmitted to powerhouse using penstock pipes. The forebay consists of a spillway to divert excess water. This maintains constant head (elevation of water) for the trubines in the powerhouse.

The forebay with spillway in the left. It also consist of pipe spillway at the center.

Penstock pipes

Penstock pipes transmitts the flow from forebay to powerhouse. Saddle support and anchor blocks are provided to hold the penstock in the fixed alignment.

Penstock alignment

Anchor block in penstock alignment

Powerhouse and tailrace

The flow from penstock strikes the turbine and generator produces electricity. The flow is then discharged back to original river. The powehouse of GMP is near the southern end of Ghunsa village.

Powerhouse	Penstock inlet at powerhouse
The penstock inside the powerhouse	Turbine
Powerhouse with tailrace outlet

Most efficient trapezoidal section of canal

The most efficient trapezoidal section of canal can be calculated as follows

Let,


Base width of the canal=B


Side slope=m (1V:mH)


Flow depth = h


Wetted perimeter= P

The cross sectional area, A=By+my^2


ie B= (A-m*h^2)/h


ie B=A/h-m*h


Wetted perimeter P= B+2*h *sqrt(m^2+1)


For most efficient channel, dP/dh=0


ie -A-m*y^2+2 y^2 sqrt(m^2+1)=0


ie B= y(2*sqrt(m2+1)-1-m)


Therfoer B/y=2*sqrt(m2+1)-1-m is the required relationship

Elementary analysis for width/height ratio of retaining masonary structure

As we know that masonry structure cannot resist tension, hence all the lateral force should be resisted by its weight component only. In this article we will derive expression for width/height ratio for a simple rectangular masonry structure.

Let,

γ=density of water

S_m=specific gravity of masonry material

S_L=specific gravity of material giving lateral force (e.g. water, soil etc)

h=height of the structure

x=width of the structure

W=weight of structure=h*x*s* γ

μ= coefficient of friction

Case1: For overturning

Moment dut to lateral force=moment due to weight of the material

½* γ*s_L*h²*h/3 =W*x/2

Or, ½* γ*h²*h/3*s_L = γ *s_m*h*x*x/2

Or, (x/h)²=(s_L/(3*s_m))

Or, x/h=sqrt(s_L/s_m/3)

For water s_L=1;for stone masonry s_m=22/9.81=2.14

Therefore, x/h=0.394≈0.4

Case2: For Sliding

Horizontal force=friction factor*weight of the structure

½* γ*s_L*h²= μ (γ*s_m*h*x)

Or, x/h=s_L/(2*s_m* μ)

For water and stone masonry and using μ=0.65

x/h=0.359≈0.4

Thus from above derivation we see that the minimum base width/height ratio of the rectangular block to resist the lateral (triangular here) force with safety factor 1 is 0.4.

With safety factor of 1.5 the minimum width/height ratio becomes 1.5*0.4=0.6.

Derivation of Combined Angle

Abstract: Derivation of combined angle may become useful when you want to know the magnitude and direction of force due to bend in both XY and XZ plane. For eg in design of bend in pipeline.

Let us consider a straight line which deflects at O along OA as shown in the figure. The deflection angles are also shown in the figure.

Let R be the position vector of A. OB is projection of OA on XY plane and AB is projection of OA on a plane parallel to YZ plane. Similarly, OC is projection of line OB in X axis and BC is projection of OB on axis parallel to Y axis.

From figure it can inferred that

OB=R cosα

AB=R sinα

OC=OB cosβ = R cosα cosβ

BC= OB sinβ =R cosα sinβ

Therefore, the position vector of A is OA which is given by

R=|R| (cosα cosβ i + cosα sinβ j + sinα k )

And the unit vector along R is given by

r= (cosα cosβ i + cosα sinβ j + sinα k )

Now the combined deflection angle is given by

r . i =|r| |i| cosδ

Or, r . i =1*1 cosδ

Or, cosδ = cosα cosβ+0+0

Or, δ =cos^-1(cosα cosβ)

The angle δ lies in the plane OAC. This plane is shown in the figure in hatch line.

Forces

If F be the magnitude of force due to the deflection δ (e.g. deflection in pipeline) then the vertical and horizontal component of this force is given by,

F_x1 =F r . i =F cosα cosβ

F_x2 =F r . j =F cosα sinβ

F_x =F

=F cosα

F_y =F r . j

=F sinα

MEASUREMENT OF LAND IN NEPAL

In Nepal we use different units for measurement of land. In hilly regions we use Ropani-Ana-Paisa-Dam system while in Southern parts i.e. at Terai region we use Bhigha-Kattha-Dhur system.

The conversion between these units and also to the SI unit is essential as we come across this situation often.

The conversion factor for these units is as follows

Ropani-Ana-Paisa-Dam system

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  1 Ropani =16Ana
  
  
  
  
  


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  1 Ana =4 Paisa
  
  
  
  
  


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  1Paisa =4 Dam
  
  
  
  
  


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Bhigha-Kattha-Dhur system

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  1 Bhigha= 20 Kattha
  
  
  
  
  


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  1 Kattha= 20 Dhur
  
  
  
  
  


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For inter conversion between Ropani and Bhigha

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  1Bhigha=13 Ropani
  
  
  
  
  


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Similarly in standard units we may use

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  1 Ropani =74feet X 74 feet
  
  
  
  
  


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  1 m=3.218 feet
  
  
  
  
  


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An Excel sheet has been developed for the general use which can be downloaded in this page.