I would like to dedicate this thread for people who want to contribute to any things in the field of science, engineering, technology, or medical, and give FREE knowledge with their expertise in the particular field.

SSCI itself is a good educational source for a lot of projects and knowledgeable experts (not the unknown ones as are usually mentioned in Indian dailys) contribute without us going around in Google and searching for it. However maybe we can keep this thread for people who have questions in some field and hopefully can find answers here.

PLEASE DO NOT ASK FOR COMPUTER CODES AND SOLVE A CHEMISTRY EQUATION HERE!!

To start with I would like to ask Civil Engineers this question:

I have often seen in the US when the buildings are built, they are built using steal beams. They make a skeleton using the steel beams and then build the wall and structure around it. Whereas in India, we have the steel rods that are erected and then a pillar is built around it by pouring cement between the rods. Millions of such rods are used for construction of these buildings.

What is the reason for doing so and why the difference in adaption of different methods in both the countries.

^^
may be because we have cheaper concrete than them but yeah thats true not only in India but nearly most other countries use RCC than steel frames
may be this (http://www.iaarc.org/publications/fulltext/Time_and_Cost_Evaluation_of_Construction_of_Steel_Framed_Composite_Floor_with_Precast_Concrete_Floor_Structure.pdf) can help you
but didn't help me much still wondering why

Few more topics that need to be taught by professionals.

* How are concrete roads laid
* Various types of roads and ways of layering / making etc.
* Types of concretes
* Slab building know-how
* Tower Cranes - how do they go UP (increasing height every storey upon completion)
* Guidelines / Rules / Regulations for Indian Construction Industry workers (laborers etc)

The list will go on but laypersons certainly need inputs from professionals like KB / Engineer Akash / Rohit.Engineer & Euromast (who is also from engineering profession)

Hope to see this thread become more EDUCATIONAL than OT discussions

PRASAD, I have the same question as you regarding the tower cranes. I have wondered as well how do they go up with every additional level/floor.

What is the approximate depth calculation for the depth of the foundation for a supertall project? is it similar to regular buildings or is the foundation/trusses/core different for projects like World One vs Antilla for example?

To start with I would like to ask Civil Engineers this question:

I have often seen in the US when the buildings are built, they are built using steal beams. They make a skeleton using the steel beams and then build the wall and structure around it. Whereas in India, we have the steel rods that are erected and then a pillar is built around it by pouring cement between the rods. Millions of such rods are used for construction of these buildings.

What is the reason for doing so and why the difference in adaption of different methods in both the countries.

Don't know the correct answer for it but this thread in skyscraperpage may help you to find some reasonable answer.

http://forum.skyscraperpage.com/showthread.php?t=122219

* Tower Cranes - how do they go UP (increasing height every storey upon completion)



PRASAD, I have the same question as you regarding the tower cranes. I have wondered as well how do they go up with every additional level/floor.

Tower crane assembly.
RB91Sm-kGJ8

Its called as kangaroo crane

What is the approximate depth calculation for the depth of the foundation for a supertall project? is it similar to regular buildings or is the foundation/trusses/core different for projects like World One vs Antilla for example?

No approx calculations available,all depends on the site conditions.

Supertalls go for pile foundations,demands transfer of loads to hard strata below.

*Piles are designed to carry axial loads with some lateral stiffness.

---Becomes critical during liquefaction where in soil flows like water,

A simple analogy: take a broomstick pull out one strand(A pile here).Hold that strand in ur left hand(wrapped you palm) while compressing the top and bottom of it,your palm which is wrapped around it gives good lateral stiffness,the moment you remove ur palm it becomes slender due to the lack of surrounding stiffness(soil during eq flows like water,thereby rendering no lateral stiffness to the pile,which buckles and fails),it eventually breaks.


*Sufficient lateral strength is achieved by optimum spacing of piles during their grouping.Many more advanced methods are there leave it to the engineers. :cheers:

*For greater depths,shoring etc becomes and issue.The earth tends to cave in,sufficient shoring methods are adopted.Well is created around the site,which can retain earth+ water.

^^Base isolation etc for mid rises is a vast area....

Tower crane assembly.
RB91Sm-kGJ8

Perfect, thanks!

No approx calculations available,all depends on the site conditions.

Supertalls go for pile foundations,demands transfer of loads to hard strata below.

*Piles are designed to carry axial loads with some lateral stiffness.

---Becomes critical during liquefaction where in soil flows like water,

A simple analogy: take a broomstick pull out one strand(A pile here).Hold that strand in ur left hand(wrapped you palm) while compressing the top and bottom of it,your palm which is wrapped around it gives good lateral stiffness,the moment you remove ur palm it becomes slender due to the lack of surrounding stiffness(soil during eq flows like water,thereby rendering no lateral stiffness to the pile,which buckles and fails),it eventually breaks.


*Sufficient lateral strength is achieved by optimum spacing of piles during their grouping.Many more advanced methods are there leave it to the engineers. :cheers:

*For greater depths,shoring etc becomes and issue.The earth tends to cave in,sufficient shoring methods are adopted.Well is created around the site,which can retain earth+ water.

Interesting - can you explain a wee-bit more on the dissemination of axial load to the foundation? How does piles achieve this and is thus used for Supertalls as opposed to any other tech?

Tower crane assembly.
RB91Sm-kGJ8

That makes me wonder how they dismantle it... Although, no need to answer that (not like you were going to anyway) as it'll only confuse me more.

To start with I would like to ask Civil Engineers this question:

I have often seen in the US when the buildings are built, they are built using steal beams. They make a skeleton using the steel beams and then build the wall and structure around it. Whereas in India, we have the steel rods that are erected and then a pillar is built around it by pouring cement between the rods. Millions of such rods are used for construction of these buildings.

What is the reason for doing so and why the difference in adaption of different methods in both the countries.

The weight of the building is very important while designing and for the cost / financial feasibility.

In India, we really do not have the skyscrapers as you have in US or other developed countries. There, they also use plaster boards partitions to reduce weight.

As you go taller, weight reduction is achieved by steel frames, whereas the concrete frames are cheaper / sturdier for low rises.

The technology available in India is also limited. Superior quality welding is required and the quality of steel also matters.

People here prefer sturdy concrete buildings. (We initiated a steel frame building in Coimbatore and it was stopped before completion since the developers could not convince their clients).

If the clients are not able to fix nails on the walls in India, then you lose them. Even electrical wire chasing keeps happening. Plaster walls are not preferred due to this.

But as we go for tall buildings, we have to adopt these technologies. No other go.

The technology available in India is also limited. Superior quality welding is required and the quality of steel also matters.



We have worst workmanship in India when it comes to steel construction.

I am a part of this project a PEB building in Navi mumbai (G+3, Heavy loading)which demands high grade steel of 355 mpa yield strength.

In India TATA structura is the sole steel section producer with max 310 mpa grade.TATA celcius is 540 mpa UTS,which is not produced in India.

Sourcing such high grade steel from abroad is very costly.Somethings are not in Structural engineers hand,when structures demands it we ought to satisfy it :lol:

High rise buildings can be done with Concrete as well,like CFT etc...Example Taipei 101,no rule that high rise buildings need to go for Steel,though steel has tremendous advantages in high rise construction.

But as we go for tall buildings, we have to adopt these technologies. No other go.


Not necessarily,High rise buildings can be done with Concrete as well composite construction,like CFT etc...My Btech thesis was on CFT :cheers:

Example Taipei 101,no rule that high rise buildings need to go for Steel,though steel has tremendous advantages in high rise construction.

Structural engineering is nothing but hard core engineering :cheers:

As you go taller, weight reduction is achieved by steel frames, whereas the concrete frames are cheaper / sturdier for low rises.

.

True,creep is the biggest enemy of Concrete under heavy loading,like how water+ oxygen is for steel. :cheers:

Steel is preferred in high rise building for better seismic performance will explain later

^^

Thanks guys.

Kannan, I guess when you say plaster walls, you are referring to dry walls, right?

India is the 4th highest iron producing country in the world. I guess since we are so used to the conventional methods, we are not approaching new technologies? As Akash said, unless there is a demand for it.

^^
As Akash said, unless there is a demand for it.

Exactly,India might be 4th biggest iron ore producing nation,but we are not consuming it.Most of it is being exported.Those beautiful structures in Beijing built for Olympics are all done by Iron ore exported from Bellary,India.

We are slowly seeing construction steel manufacturers setting their foot in India.

JSW-Severfield JV set to open Bellary unit

JSW Severfield Structures, a 50:50 joint venture between JSW Steel subsidiary JSW Building Systems and UK-based construction steel supplier Severfield Rowen, will commission its steel fabrication plant in Bellary on November 17.

“The joint venture has so far invested over £25 million in the Bellary production lines. The factory will have an annual capacity of 35,000 tonnes of fabricated steel. It has started formal production to some extent. With the new production lines in Bellary, the JV will offer fuller solutions to clients,” sources said.

Besides conceiving, designing, fabricating and erecting structural steelwork for the domestic market, the new plant will serve requirements of Severfield-Rowen’s production lines in Northern Yorkshire, which is the largest steel fabrication facility in the UK.

The new unit will source steel plates and galvanised products from JSW’s plant at Vijaynagar in Bellary district, providing a value-addition channel to the domestic steel producer. The project is said to have been financed on a 2:1 debt-equity ratio, and is expected to generate annual revenues of around Rs 400 crore.

The facility has been designed primarily to cater to the need for beam, column and plate girder structures from offices, malls, hotels and bridges. The target market will initially be commercial structures and simple highway bridges, mainly in western and southern India.


TATA celcius is actually TATA Corus product manufactured abroad.High grade steel will soon be a common thing in India,as India grows our structures will demand high and higher stuff. :lol:

If the clients are not able to fix nails on the walls in India, then you lose them. Even electrical wire chasing keeps happening. Plaster walls are not preferred due to this.



Kannan ji perfect catch,I have experienced this too...:lol: Forget the clients,majority of architects in India are very unprofessional.

Doing a project where the slab span is pretty high - architect does not want any column to span between and more over wants a clean soffit + lesser slab depth.

i was like fcuking these architects need to be taught basics of structural engineering before they vomit crap on sheets.

He was bent upon getting flat slab done,but since it was a single panel and normally flat slabs need continuous panels atleast 3-4.I dropped the idea of flat slab system.

Next i suggested PT slab,he found it suitable until I sid you cannot cut the slab in future for any reasons.He was like nooooooo..I gave up..

Finally,My senior suggested filler slab and sent him away:nuts:

this is what happens when - we have serial design process---we need to follow parallel design process which involve both architects and structural engineers during conceptualizing.

Architects :|

@ Akash & Architects:

Not all architects are so dumb man. :)

They dream and you Structural guys have to make it real. Thats all.:lol:

I have both Architects & Structural guys in my firm and I am the peace maker.

I have been trying to bring in modern technology into the projects which we do but I face tremendous resistance from all quarters - educated to uneducated.

The main stumbling block is - Chalta Hai attitude. Perfection or Near Perfection is taboo.

Actually better planning (even taking more time) and by using better technology, we can really reduce the cost & time of construction as a whole. But very few realise this.

We introduced Post Tension Slab for the first time in India (in Chennai done by VSL, Singapore), a decade or more back. We had a height restriction problem since the location was under Airport Flight path funnel. By using PT slabs, we reduced the height of each floor and were able to build one extra floor within the total height permitted.

The developer spent upto 30% extra on basic structure due to PT slab as the steel pylons were imported and we had to use the trained labor from Singapore / Thailand. But he got one more floor and the extra rent from the same paid for the extra cost within a few years.

Similarly we use Precast / Prefab construction for Govt schools / Primary Health centres/ Military bases, mainly in rural areas and border areas. The construction is quicker, cheaper and eco friendly.

Affordable Housing / Low cost housing by using this technology can cater to / solve the huge demand for housing by lower middle class in India. But very few developers have accepted this.

@ Akash & Architects:

Not all architects are so dumb man. :)

They dream and you Structural guys have to make it real. Thats all.:lol:

I have both Architects & Structural guys in my firm and I am the peace maker.

Yes,I have met some excellent architects too,most of them are heavily experienced and they have learnt basics of structures too.

Good that your firm follows parallel design process.

Actually better planning (even taking more time) and by using better technology, we can really reduce the cost & time of construction as a whole. But very few realise this.


Affordable Housing / Low cost housing by using this technology can cater to / solve the huge demand for housing by lower middle class in India. But very few developers have accepted this.

Rightly said sir,

Mysore won an award under JNNURM for making use of mivan technology for low cost housing.

BTW low cost housing using exposed concrete/rcc walls is catching up in India

^^

So this school stopped taking new admissions