Question

A braced frame steel building is to be designed to resist blast loads. The building is assumed to be at “medium” risk of a placed bomb. Individual members in the building are to be analyzed as separate one degree-of-freedom systems. Consider a W14x34 steel column having a yield strength of 50 ksi. The building floors are 12 feet between story levels. The column is pinned at both ends. The column supports exterior cladding; the bays are 24 feet on center.See Figure 1 for the blast loading for the “medium” risk scenario. Determine the blast load to be applied to the column. Model the column as an equivalent elastic system and calculate one second of the displacement response time history. Determine the maximum displacement and bending moment.

20-0 20-0 20-0 umn to be 4-024-024-024-0" lumn to be designed 2-0 2-0 LEVATION ATBlast Ft Weight 100 0 deg -reflected (deg) go deg - incident Range b) Alpha 0 Load 7.62 Duration msec e 20.28 (psi Impulse 77.39(psi-msec) Pressure 1.36 Fumsec) Aivl msec Shock Vel Arrival Close un ,,Se.nc. This program is provided courtesy of Applied Research Associates Security Engineering Group Contact: (ph) 601638.5401 (e-mail) İ[email protected] Figure 1 -Blast Load for Problem 1, "Medium" risk

Answer 1

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