Effects of In-plane Restraint on Progression of Collapse in Flat-Plate Structures
This paper presents experimental and numerical studies of reinforced concrete flat-plate structures. Experiments were performed on six interior slab-column connections without structural integrity reinforcement to examine their punching and postpunching behaviors. The test variables included slab tensile reinforcement ratio and lateral restraint at the slab boundary. The experiments indicated that, under the level of restraint achieved in the tests, the compressive membrane action could enhance the punching resistance by as much as 9.5%. The tests also showed the slab-column connections without continuous compressive bars at the columns had a postpunching loading capacity of about 50% of the failure load, but this residual capacity cannot be maintained under large deformations. It was found that anchoring the slab tensile reinforcement into slab by hooks provided an alternative approach to achieve stable postpunching capacity. The numerical simulations confirmed the effectiveness of a macromodel for flat plates. The analyses also indicated the effects of compressive membrane action on punching resistance is a function of slab in-plane restraint and can significantly increase the resistance of a flat-plate building to progressive collapse.
Orton, S. L.,
Effects of In-plane Restraint on Progression of Collapse in Flat-Plate Structures.
Journal of Performance of Constructed Facilities, 31(3),