Study On Mechanical Properties Of Reinforced Concrete Members At Different Loading Rates

Recently, with the permanent and fast growth in economy, there is a significant development in the area of the architecture and structural engineering. The reinforced concrete(RC) structure is one of the most widely used in many kinds of structural types. Meanwhile, with the development in the design and construction of super high buildings, structures with big span and flexibility, structures may probably be effected by the dynamic loading caused by the wind or earthquake. Concrete and steel are the typical rate-dependent material. So the mechanical behaviors of the RC structure are affected when the component is applied by dynamic loads.Dynamic experiment of RC members at different loading rates was carried out with the MTS electro-hydraulic servo system to study the effect of loading rates on the mechanical behaviors of RC beams and columns. The monotonic loading and cyclic loading under different loading rates are chosen. The loading rates are controlled by the displacement, namely O.lmm/s,0.5mm/s, lmm/s,5mm/s and10mm/s. The dynamic data acquisition system DH5937is used to collect test data, draw beams and columns bearing capacity curves with experimental data. And then the experimental data from yield load, ultimate load, energy, ductility and stiffness degradation under different conditions are analyzed. During the test, observe and record the destruction of beams and columns are observed and recorded.The ANSYS finite element software is used to simulate the testing process, analyze the bearing capacity under different loading rates with rate-dependent model, and compare the experimental results and simulation results.Conclusion:(1) With the loading rate increasing, the ultimate load and other mechanical properties of RC beams in the monotonic and cyclic loading are improved; the energy dissipation of reinforced concrete beams gradually increases; with the increasing of loading rates, the cracks distributed more equably, but their depth decreased.(2) With the loading rate increasing, the ultimate load and other mechanical properties of RC columns in the monotonic and cyclic loading are improved; the energy dissipation of reinforced concrete beams gradually increases:the column stiffness degradation is accelerated. (3) With the loading rate increasing, the bearing capacity of beams and columns are improved.This article has some theoretical significance for engineering applications. At the same time, use simple component changes in mechanical properties under different loading rates to simulate the dynamic loads on the entire structure.