If so, here would be the values:
Mass of a skyscraper: 222,500 imperial tons; 201,814,058.957 kg
Density of structural steel: 7,850 kg/m3
Density of reinforced concrete: 2,500 kg/3
Mass Ratio: 1/6 steel, 5/6 concrete
Mass of steel: 201,814,058.957 x (1/6) = 33,635676.493 kg
Mass of concrete: 201,814,058.957 x (5/6) = 168,178,382.464 kg
Volume of steel: 4,284,799,553.225 cm3
Volume of concrete: 67,271,352,985.639 cm3
Frag (Steel): 891,238,307,070.882 joules
Frag (Concrete): 672,713,529,856.387 joules
Total: 1.56395e+12 joules, or 373.793 Tons of TNT (8-A)
V. Frag (Steel): 2.43591e+12 joules
V. Frag (Concrete): 4.11701e+12 joules
Total: 6.55292e+12 joules, or 1.56619 Kilotons of TNT (Low 7-C)
Pulv. (Steel [Average of 655 J/c3]): 2.80654e+12 joules
Pulv. (Concrete): 4.10355e+13 joules
Total: 4.3842e+13 joules, or 10.4785 Kilotons of TNT (7-C)
I can't find a vap. value for concrete, but vap. for the steel alone is: 2.61e+14 joules, or 62.383 Kilotons (7-C+)