I would like to start my construction company ,i would like to know list of project architects and engineers having projects in chennai?

If you are going to have a construction company you need to be able to find out information on your own or through local contacts. I doubt there are any people logging into Answers with that type of information.

I would assume there are ways to find the phone numbers of various architects and engineers in Chennai. I would start there by calling and asking what kind of work they have. This sort of thing is done in the US all of the time. If nothing else you will end up with a list of names and phone numbers that might be useful in the future.

If the phone system there is like it was in Thailand a few decades ago, where phones were sold with the property and private directories covered the lack of knowledge of the government phone company as to who actually used them. On the other hand, if Chennai requires building permits like in the USA, then you have a chance of going down to the government offices and copying off information on who is active.