Inelastic Behavior of R/C Cylindrical Shells

The elastic and inelastic behavior of uniformly loaded short, intermediate, and long reinforced concrete shell roof structures is studied with a series of small scale model shells. All shells had end diaphragms and vertical edge members on the free edges. The elastic range of behavior of the models represented only a small fraction of ultimate load capacity, and correlated well with theoretical predictions. Cracking occurred at or near the working load level, with subsequent reductions in shell stiffness; increasing loads led to failure modes varying from a beam failure in long shells, combined transverse, longitudinal, and diagonal corner cracking in intermediate length shells, and rather abrupt transverse and diagonal cracking in short shells. Ultimate load capacities ranged from about 200 to 1000 psf, increasing almost linearly with increasing radius to length ratio.