Experiment Research And Non-linear Stochastic Evolution Analysis Of RC Short-Leg Shear Walls

Nonlinearity and randomicity are focused and difficult problems in concrete structure engineering field, their coupling results in comlex stochastic evolution in different response level. Considering the physical background, two types of short-leg shear walls are investigated in experiment and theory.Experimental design is pivotal segment in the whole test. Structure design, material preparation, specimen construction and loading system are fabricated strictly so as to eliminate other uncertain factors. So it can be considered that stochastic responses are mainly from concrete. It offers a base in order to analyse subsequent experiment data.Experimental phenomina of different specimens are contrasted. Local destructive phenomena and the whole failure characteristic make great differences. Cracked feature, yield characteristic and destructive phenomena show that coupling of concrete randomicity and non-linearity has notable effects on structural responses.Experimental data are analysed in static tests on two types of short-leg shear walls specimens respectively. The responses have distinct stochastic evolution feature in Load-displacement curves, strain curves, partial relative displacement curves and typical cross-sections mechanical behavior. Moreover, evolution precesses of structure responses become more and more complicated with response level refining. It can be concluded that coupling of concrete non-linearity and randomicity induces stochastic redistribution of inner forces.Based on the damage energy release rate-based elastoplastic damage constitutive model for concrete, deterministic nonlinear behavior of short-leg shear walls is investigated. By means of material mean mechanical index, nonlinear responses of load-displacement curves could be forecasted in acceptable scope, however, strains and partial relative displacement responses are just described in general tendency because of notable variability. So it is necessary that PDEM is carrid out.In the frame of stochastic damage mechanics for concrete, based on the probability density evolution method and the elastoplastic damage constitutive model for concrete, non-linear stochastic evolution of structures is described through sample tracks, ensemble numerical characteristics and probability density. Furthermore, P-â–³cures, concrete and reinforcement strains cures are conformed to experimental results in ensemble numerical characteristics. Multi-peaks and multi-ridges phenomenons appear in probability density function evolution surfaces of the different response level. It shows that non-linearity leads to random fluctuation of responses, and randomicity results in complex nonlinear evolution tracks. So nonlinear and stochastic responses are complex interacting processes.In the end, a concise conclusion has been drawn and some potential problems are discussed for further studies.