Montgomery Civic Center

n 1970, engineers from Fraoli-Blum-Yesselman Associates began a project to design the proposed Hartford Civic Center Arena. The engineers came up with a unique roof frame design they called a space roof. The 300 by 360 ft. roof frame consisted of top and bottom square grids with joints 30 feet on center, connected by diagonal bars that caused staggered nodes on the top and bottom grid bars, resembling pyramid trusses when they were finished. This non-standard design was intended to save on costs and additionally provide some other features such as better drainage and the elimination of bending stresses.

The construction of this unique roof design was done entirely on the ground to save time and money. After being built, the frame was lifted into place using hydraulic jacks located on top of the four pylons of the building. The roof was completed in January of 1973 and the entire project sometime in 1975. …show more content…
Only a few hours after a crowd of five thousand had left the Hartford Civic Center Coliseum, the roof of the building collapsed under the weight of the heavy snowfall. (Credit: LZA Investigation Report)

The Cause

The Hartford Civic Center's failure cannot be blamed on the weather. A three-member panel of organizations investigating the collapse found its cause to be due to three design problems:

· The top layer's exterior compression members on the east and the west faces were overloaded by 852%.

· The top layer's exterior compression members on the north and the south faces were overloaded by