Study on the Mechanical Performance of H-Shaped Steel-Concrete Laminated Plate Composite Beams under Negative Bending Moment

To make the construction of assembled steel-reinforced truss concrete laminated plate composite structure faster, safer, and more efficient, this paper proposes an H-shaped steel-reinforced truss concrete laminated plate composite structure with new angle connectors embedded in the precast bottom panel. Through experimental studies on the H-shaped steel-concrete laminated plate composite beams with precast bottom panels protruding from the bent-up bars, precast bottom panels with embedded new angle connectors and laminated whole cast slab, the similarities and differences of load-deflection, deflection distribution, interface slip, crack distribution and cross-section strain distribution of three groups of composite beams under negative bending moment were analyzed and compared. Using ABAQUS finite element software, we established a finite element model and found the numerical simulation results were in good agreement with the experimental results. Based on this, five groups of finite element models were established for parametric analysis to investigate the effect of concrete strength on the flexural load capacity and flexural stiffness of the steel-laminated plate composite beams with embedded angle connectors. The results of the study show that the combined performance of the H-shaped steel-concrete laminated plate composite beams with the new angle connection embedded in the precast bottom panel was better and the flexural stiffness was greater. The slippage of the H-shaped steel-concrete laminated plate composite beams with embedded new angle connectors in the precast bottom panel was less than the slippage of the precast bottom slab bent-up bars protruding and the laminated cast plate, with the maximum slippage being only 1/2 of the precast bottom panel bent-up bars protruding. In the composite structure of H-shaped steel-concrete composite slabs under negative bending moment, shear angle connectors can replace the bent-up bars protruding from the laminated bottom panel to achieve without extending the reinforcement of the laminated bottom panel.