Nonlinear bending and experimental validation of circular reinforced concrete and steel-reinforced concrete thin plates with compliant support contour

This study investigates the nonlinear bending behavior of circular thin reinforced concrete (RC) and steel-reinforced concrete (SRC) plates under short-term and long-term loading, with particular attention to the influence of support contour compliance. A calculation framework is developed for the stress-strain analysis of axisymmetrically loaded circular plates by accounting for geometric nonlinearity, material nonlinearity, reinforcement effects, and time-dependent deformation. Experimental studies were carried out on circular RC plate models interacting with a support ring, and the measured deflections were compared with theoretical predictions. The results show that the proposed model captures the main features of plate deformation, including the nonlinear increase in deflection with load and the redistribution of the stress-strain state near the contour. For the considered loading cases, the discrepancy between calculated and experimental deflections did not exceed 17 %, which confirms the engineering applicability of the developed approach. It is also shown that support contour compliance significantly affects the long-term behavior and load-bearing response of the plates. The obtained results can be used to improve the design and assessment of circular RC and SRC plates, especially in structures where nonlinear effects and contour deformability must be taken into account.