Finite Element Analysis on Structure in Hyatt CollapseMeng Lu1, Jiaying Gao1

Department of Mechanical Engineering

* Values are arbitrary and only intend to cause beam failure so maximum loading of each design can be verified

Background• In July 1981, two suspended walkways at the

Kansas City Hyatt Regency hotel collapsed• During investigation of National Bureau of

Standards, the key connection on the supporting beam of the walk way is changed, shown in Fig. 1 below

• Inner rod on modified beam carries weight from second floor

Finite Element Model• Geometries of the 3D beam model for both

designs shown in Fig. 2• Only rod-beam connection simulation to

observe damage on beam due to loading• Loading condition based on actual beam

usage• Maximum force causing damage will be used

to evaluate effect of new design in terms of load carrying capacity

• Precise beam deformation are simulated and will be used to compared with physical evidence

Goal of the Project• Through Finite Element Method, applying

loading on both designs to cause failure.• Investigate both designs’ loading carrying

capacity and determine whether the modified design is as safe as original one (which was validated by designer)

Modified Original

Fig. 1 Modified and Original Design of Connection

Fig. 2 Modified (a) and original (b) beam models

(a)

(b)Fixed

130 kN 130 kN

140 kN

FEA Results:

Applying Load

Applying Displacement

• By applying load, accurate contact between rod and beam simulated

• Better loading history of outside rod shown below

Modified Design

Original Design

Fig. 3 Deformed Beams: Modified (Upper) and Original (Lower)

*Welded region marked in red

Fig. 4 Side view of two design before and after deformation

Accurate force compared to NBS test result

Conclusion1. Modified beam can only stand 21 kips, around 3.5

kips less then original design2. The modified beam is carrying weight from current

floor and 2nd floor. Thus the welded region is more likely to fail.

3. In original design, beam only carries weight from current level, thus less stress on the welded region

Beam has two sides welded together Results Discussion:

8” 4”