I have found few links.... provide helpful for you. Please check the attached links

Kunal

http://www.ijsr.net/archive/v3i2/MDIwMTM5NTY=.pdf

http://ijret.org/volumes/v02/i08/ijret_110208050.pdf

http://www.estij.org/papers/vol3no12013/20vol3no1.pdf

http://cafetinnova.org/wp-content/uploads/2013/05/02050341.pdf

Here it is the  useful paper, enjoy reading

Here are also two general reviews, I hope useful.

There are two major reasons for the properties of concrete to decrease.

1. The used material has an transition point in the temperature region you want to use it (I.E. the degradation of portlandite at temperatures > 120 °C or the quarts transition point 572°C)

2. The amount of water which is trapped inside the concrete. If you heat up the concrete to rapidly water vaper has no time to leave the concrete through the capillary system. Depending on the water porosity ratio this could cause spelling.

Normal concretes say M20 to M 35 will easily withstand 3000C. Proper care should be required at the time of casting and curing. 

Thanks a lot for all for the inputs

More literature about fire and concrete.  Adding polypropilene fibers avoid spalling of concrete

Heating induces a range of physical and chemical processes from ambient up to melting at temperatures above 1000oC. Some elements of concrete begin to melt at around 1060 oC, and ordinary Portland cement paste starts to melt at 1350 oC (Khoury, 2003).The nature of these processes depends upon the mix constituents and proportions used, as well as the moisture and environmental conditions during the fire. Depending upon these factors, the compressive strength of concrete at high temperatures can, for example, vary at 300 oC from below 60% to as high 130 % of the unheated strength (Khoury, 2002).

Dear sir.

thanks for your interest in my paper. concrete with M20 and M25 grade can stand a 300C very easily with no risk. but the time that concrete may be subjected to this temperature should be very well encountered so as to let concrete last for long time. the preferred time is not more than 3 hrs.

bassam