Wednesday, March 15, 2006

Milad Tower

Four tallest structures in the world are:

1. KVLY-TV mast, Blanchard, North Dakota, USA, 629 m (2063 ft) high;
2. Petronius Platform, Gulf of Mexico, 610 m (2001 ft) high;
3. CN Tower, Toronto, Canada, 559 m (1865 ft) high; and
4. Milad Tower, Tehran, Iran, 435 m (1427 ft) high.

Three of these tallest man made buildings are seen to be in North America, but the fourth and third are enough reasons for me - as a structural engineer - to feel proud, being in my first and second countries, respectively.

The Rls750 billion ($95 million) Milad tower, is part of The Tehran International Trade & Convention Centre. The project, first scheduled to be completed in 2005, and now estimated to be finished in March 2007, includes the Milad telecommunication tower offering rotating restaurants at the top with spectacular views of Tehran, a five star hotel, a convention centre, a world trade centre, and an IT park. The tower will cover over 95% of Tehran for communications services.

The complex also features a parking area of 27000 square metres, an exhibition hall, and an administrative unit.

Although known as the fourth tallest free standing (cantilever) structure in the world, it is the first considering the vast functional 12 storey structure on the top, also the only tower with octagonal base, symbolizing traditional Persian architecture.

The overall height of the tower is 435 metres from base to the tip of the antenna, while the reinforced concrete shaft is 315 metre high. The shaft weighs 80000 metric tonnes, and is constructed using sliding formwork. The raft foundation is 66 metres in diameter and 9 metres deep.

Milad means "birth" in Persian.

Monday, March 6, 2006

Brief History of Computers in Structural Engineering

1976- This is the first time I’m working with computers. This is my second year at Tehran Polytechnic (Amirkabir University of Technology), and as students of "Numerical Analysis" we have access to an IBM 370 mainframe. The input data is given in the complex formats of Fortran IV using the punched cards, and the output device is a large size printer. The system as a whole occupies some 4000 square feet.

1979- We use the same computer, now in analysis of our steel and reinforced concrete final projects, using the only reliable software of this time, STRESS II. This program is written in FORTRAN IV using the stiffness matrix method, for plane frames only. It takes some one hour to complete the analysis of a 5 storey 5 bay plane frame, for 2 load cases and 3 load combinations, enough for elastic (allowable stress) design.

1983- The first job of my career is started in an office, fortunately equipped with the first personal computer I have ever seen and used: Radio Shack 16, with 16 KB memory, and a BASIC86 interpreter. People are strongly advised not to say kilo bytes (to computer experts, it's a crime!) as kilo means 1000, but this new K means 1024 instead. My supervisor, the chief structural engineer, has prepared a few useful programs for analysis of plane frames using Takabeya Method (a moment distribution method just like Cross and Kani, but much easier and faster), and design of steel and reinforced concrete members using AISC and ACI respectively. There is not any local code in Iran yet, so most engineers use the American codes (UBC, ACI, and AISC), while others use British (BS), French, or German (DIN) codes of practice. A few months later... an extra memory of 48 KB is purchased and added to the system, which makes it 64 KB in total. Wow... 64 K-bytes! Who could even think of it?! Now it is time to start writing a brand new program for frame analysis using stiffness matrix method. It works great for 2 to 5 storey buildings. But in solving the equations, we'd rather use Cholesky Method which is faster than Gauss Elimination Method. The results of the analysis are exported to a cassette, and then imported to design programs. I’m so happy that with these programs, we are not using the computer as a typewriter!

1984- Same firm: a big step forward, with an NCR DM5 personal computer, using an MS Dos operating system for the first time, with 640 KB memory now called RAM, with a couple of 5-1/4" floppy disk drives, and 2 hard disks each 5 MB. It’s unbelievable... 10 MB of storage! It’s enough for a large size m storey n bay frame... and even more unbelievable is the speed of access to the hard drive, you say what file you need, and there it is; you don’t have to find the beginning of the file as you did on cassettes before, and you don’t have to verify the file loaded either. It’s now possible to store a few of the photos which would be taken some 20 years later by digital cameras, in the hard drives! The processor is now called 8088, and you should still wait a few more years to hear about the 80X86 series of computers, known as IBM compatible.

1991- The new company I join, has recently purchased the first 80286 generation computer, still 640 KB RAM, but with a hard drive of 40 MB. MS Dos 5 is released, and the very first version of AutoCAD is under curious investigations by some companies. There is not any structural analysis reliable software in the market yet.

1993- The processor is upgraded to 80386, and the hard drive is increased to a storage capacity of up to 80 MB. The R10 AutoCAD is now widely used in engineering offices. PC Tools and Norton Commander are now replaced by a new software released by Microsoft, Windows 3.1. It does whatever needed in managing the files, that is, copies, deletes, and renames files very easily at a glance. Fortran, Cobol, and even Pascal are almost forgotten, and everybody talks about new versions of BASIC which are called Quick Basic and GW Basic. First versions of Berkley SAP80 structural analysis software is capturing the market. But the format of data input as well as output process is a real pain. It’s neither as interactive as STRESS II before, and nor as easy as the graphic versions to come after 2000, but is a powerful program in analysis of plane and 3-D frames instead.

1995- 90's versions of SAP are replacing SAP80. AutoCAD R12 is used widely. Not many rulers, pens, and erasers may be found in engineering offices any more! New Windows 95 is not only a powerful file managing tool now, but also an incredible operating system based on MS Dos 6.2.

1998- Processors are upgraded to 80486, and in a few months will be replaced by 80586 or Pentiums. AutoCAD12 is used worldwide, and Windows 98 is taking the place of the previous 95 version.

2001- High frequency processors and large size RAM's, along with GB hard disks are available now. Various versions of Windows, 2000, Millennium, and others are being tested everywhere. Most programs are now Windows oriented, and Dos programs are being forgotten little by little. After a short period, the first Windows based AutoCAD14 is replaced by AutoCAD2000. SAP2000, ETABS2000, SAFE, and many more analysis and design softwares are now used by structural engineers all around the world. Good bye FORTRAN formatting of input and output data! Try drawing your structure in a whole graphic environment instead now. Many structural member types such as plates and shells are now added to the analysis programs.

2006- Windows XP in two Home Edition and Professional categories are beeing used for years. Giga bytes sounds like jokes or kid toys now: 2 GB RAM, and 250 GB hard drive. Multimedia, DVD, flat monitors, it’s like a dream.

I often think how long it took to travel by jumbo jets instead of carts and horses, and how many years and months and days are passed since I was that much happy with my NCR DM5 with 640 KB RAM and 10 MB hard, which I used so efficiently with my own programs. It must be a dream. It is a dream... or is it?

Wednesday, March 1, 2006

Forough

The controversial and revered poet Forough Farokhzad (1935-1967) is Iran's greatest contemporary poet, one of the most influential writers of the Middle East, and one of the world's best loved women poets of the twentieth century.

During her short lifetime Forough became a legend. Having sold over a million copies of her work, Forough holds a significant place in world history because she was the first woman in twenty-five hundred years to have a major body of work published in Iran and to emerge above all of Persia's contemporary poets as the greatest poet--a woman who in the land of heroes became a heroine.

Forough was not only a polemical figure during her lifetime, but since her death her poetry has come to be a powerful anthem for freedom. During the Iranian Revolution, for example, students would publicly recite her poem "My Heart Aches for the Garden" in protest to the tyrannical Khomeini regime. In fact, her work was considered such a threat to the dictatorial policies that when her publisher refused to stop printing her poems, he was put into jail and his factory was burned down to the ground.

With rare emotional depth, Forough's work is sincere, sensual, earthy, evocative, and an intriguing combination of love story, stormy passions, loss, betrayal, freedom, and most importantly, renewal. A poet of the 1960s, her poetry reverberates with issues of love and freedom and speaks to us as much today as when she first wrote them.

Here is a translation of one of her poems, "All That Is Left Behind . . .":

Why should I stand still?
Why?
The birds have gone looking for water
The horizon has been turned upside down
And motion spills out like a fountain

As far as the eye can see
Radiant planets are spinning
Earth reaches its apogee and repeats its orbit
And the blackholes in the atmosphere
Turn into tunnels that are connected to each other
While daytime occupies such space
That in the small mind of a newspaper
Not even an earthworm can fit

Why should I stand still?
The road passes from in between the tiny capillaries of life and continues
The climate: the atmosphere surrounding the uterine ship of the moon
Destroys any rotten cells
And in the chemically charged air after sunrise
All that is left behind is sound
A sound which will become one with the particles of time
Why should I stand still?

What can a swamp be?
What can it be other than a place where degenerate insects lay their eggs
The thoughts of a morgue counting swollen corpses
A coward hides his lack of manhood in the darkness
And a cockroach . . . ah
When a cockroach speaks
Why should I stand still?

The marriage of newspaper and ink is useless
The marriage of newspaper and ink will not save a small mind
I am an offspring of the trees
Breathing stale air is oppressive
(A bird that died told me to learn its flight)

The ultimate end of all forces is unification
To unite with the source of the sun
And to disperse into rays of light
It is only natural
For windmills to dry out and crumble
Why should I stand still?

I will take the unripe sheaves of wheat to my breast
And give them milk
Sound, sound, sound
The pleading sound of clear running water
The sound of light pouring down from the stars
Over the feminine body of the earth
The sound of the union of egg and sperm
The unbound thoughts of consummated love
Sound, sound, sound, all that is left behind is sound

In the land of dwarves
The standard of measurement always orbits around zero
Why should I stand still?
I abide by the laws of the four elements
And the task of writing out the constitution of my heart
Is not the work of the blind local government

What do the long savage howls
Of the reproductive organs of animals have to do with me?
What do the infinitesimal movements of a maggot
In decaying flesh have to do with me?
My life is bound up with the bloodline of flowers
Do you understand the bloodline of flowers?

The article is written and the poem is translated by Meetra A. Sofia, American Poetry Review
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