You can not take credit on cement and steel used for construction purpose. As a manufacurer / dealer registered under excise you can avail credit on the following
1) On capital goods ( as defined under rule2 of cenvat credit rules) used in the factory of the manufacturer of the final products, but does not include any equipment or appliance used in an office. Rule 2 gives list of captial goods
2) Input used in or in relation to manufaturing of final product (Refer rule 2 of cenvat credit rule for the full defination)
The cement and steel which you are refering does not fall under any of the above category. Hence you can not avail cenvat credit on it.
Regards
Dayananda