Numerical investigation on compressive arch action of prestressed concrete beam-column assemblies against progressive collapse

To investigate the compressive arch action (CAA) of prestressed concrete beam-column assemblies, bonded prestressed concrete (BPC) assembly models were established and validated using previous experimental data. The beneficial effect of CAA on the progressive collapse resistance of BPC structures is quantified by the load increase factor eta, and the CAA of BPC assemblies with four layout schemes of prestressed tendons is investigated. Furthermore, the effect of seven parameters on the progressive collapse resistance of BPC assemblies with parabolic strands is determined. A model is proposed to evaluate the CAA of BPC assemblies. The results indicate that the CAA capacity of BPC assemblies differs with different strand layout schemes. Parabolic strands aggravate the failure of the area near the middle column; the contribution of linear strands is the smallest; the resistance of parallel strands is similar to that of X-shaped strands. Moreover, the ratio of prestressed tendons, the ratio of nonprestressed reinforcement at the top and bottom of the beam, and the section dimensions of the column have a significant impact on the load increase factor. The proposed models were validated against both experimental and simulation results with a mean error of less than 5%.