Numerical Simulation of Reinforced Concrete Piers after Seawater Freeze–Thaw Cycles

Abstract

The reinforced concrete (RC) piers of offshore bridges inevitably experience seawater freeze–thaw cycles due to the periodic movement of tides in cold climates. The damage caused by seawater freeze–thaw cycles will reduce the durability and mechanical properties of concrete, and then affect the seismic performance of RC piers. The method of seismic performance analysis on RC piers by numerical simulation is gradually emerging because the process of the conventional experiment is relatively complicated, and the heterogeneity and degradation of concrete after seawater freeze–thaw cycles should be considered. In this study, the method of meso-element equivalent and layered modeling was used to simulate a low cyclic loading test on an RC pier after seawater freeze–thaw cycles with ABAQUS software. The numerical simulation results were compared with the experimental results; the deviation value of peak load was not more than 6%, and the deviation value of peak displacement was not more than 10%. The result of the numerical simulation matched well with the experimental results, and the influence of different parameters was analyzed through the practical method of numerical simulation. It can be determined that the peak load decreased by 11%, while the peak displacement increased by 40% after 125 seawater freeze–thaw cycles. In the same 125 freeze–thaw cycles, the peak load increased by 15% and 27% while the axial compression ratio and the longitudinal reinforcement diameter increased. As the stirrup spacing of specimens decreased, the peak load remained unchanged, but the ductility coefficient of the specimens increased by 20%.

Influence of Variatropy on the Evaluation of Strength Properties and Structure Formation of Concrete under Freeze-Thaw Cycles

“…An important aspect in the study and control of the frost resistance of concrete is the possibility of predicting the residual resource or the service life of products and structures [38,39]. Another important aspect of studying the durability of concrete is the modeling of reinforced concrete structures, as well as the very mechanism of chloride penetration, considering the heterogeneity of concrete and reinforcement coatings [40,41]. To assess the frost resistance of concrete, as well as products and structures made of it, various methods were used to control the characteristics of concrete (nonlinear resonant vibration diagnostics [42], ultrasonic method [43], numerical study [44]), such as seismic resistance [45], dynamic mechanical properties [46], strength, including its distribution over the thickness of reinforced concrete elements [43].…”

Time-History Analyses on the Effect of Partial Infill Walls on the Seismic Response of a Reinforced Concrete Frame Structure

“…Improved mathematical models of physical phenomena, coupled with more and more complex numerical models of civil engineering structures, resulted in accurate assessments of their behaviour under various loading conditions. Numerical simulations are now at the heart of every major research project, from reliability analyses [1,2], to assessing the behaviour of different structures in difficult site conditions [3][4][5], to optimizing the design process and increase the safety of newly built or strengthened buildings [6][7][8][9][10], to creating intervention strategies and relief plans in case of occurring natural disasters [11]. Time-history analysis (THA) is based on direct step-by-step integration of the equation of motion in time domain considering as input either the recorded accelerograms of real earthquakes or synthetically / artificially generated ones to fit design elastic response-spectra of different design codes.…”