Mechanical properties of concrete  are related to its class. When no detailed data are available, they can be taken from the table given by eg. Eurocode 2 Part 1-1 (EN 1992-1-1).

Mechanical properties of steel also relate to its grade and can be taken after the producer (they usually publish info in catlogues).

Coefficient of thermal expnsion both for concrete and steel can be taken as 10^{-6}/ deg C. You did not write what thermal analysis you want to do exactly. If it's connected with fire, you should use Eurocode 2 Part 1-2 as suggested by Alireza.

Dear sir and madam,

Thank you for answering my question. On moving forward, I have taken problem of Simply supported RCC slab. But I dont know how to assign the RCC properties. Till now i have MANAGED to analyse concrete slab with elastic and plastic properties. (i.e. Young modulus, poisson's ratio, yield stress and plastic strain). Will you or anyone please guide me, how to go for RCC slab analysis using Abaqus? 

Regards,

Yes, the mechanical and thermal properties of concrete  are mainly related to its class. Also, you can use EN 1992-1-2 for material and thermal properties of concrete.