Thermo-Hygral Case-Study on Full Scale RC Building under Corrosive Environment and Seismic Actions

Abstract

This paper is to apply the multi-scale thermo-hygro-mechanistic modeling to full-scale RC structural systems under combined long-term ambient and short seismic actions. The authors also aim to dissolve numerical difficulty for full-scale performance assessment of huge degree-of-freedom. First, the multi-scale modeling is experimentally checked by using corroded RC columns under high axial compression. Second, the steel corrosion is computationally reproduced to a multi-story RC building under long-term fictitious ambient conditions. The seismic ground motion is subsequently applied to the corrosion damaged mockup. Beforehand, the effect of drying shrinkage, which is inevitable for structural concrete in air, is discussed so as to clarify the pure corrosion impact to the whole structural system. The steel corrosion deteriorates the ductility of seismic resistant members, but as a global influence, steel corrosion is validated to reduce the base-shear input of floors owing to the decayed stiffness by corrosion. Through these case-studies, the authors raise the points of discussion to take into account the local and global effects of corrosion all at once for seismic performance assessment, and that the knowledge solely on the capacity of corroded RC members cannot lead to an engineering solution.

The Influence of Interlock Loss between Rebar and Concrete on Bond Performance of RC Member

“…The three-dimensional nonlinear finite element analytical system "COM3" was used for the analysis [28]. This system introduced a six-directional fixed smeared crack model, and its applicability to various reinforced concrete structures as well as composite structures with steel-concrete boundary has been verified in the past researches [21,[28][29][30][31][32]. The summary of constitutive laws of compression, tension, cracked shear, and joint element are shown in Figure 8.…”

Effect of early age drying shrinkage on the seismic response of RC structures

“…In [17], numerical simulations using a Thermo-Hygral model were performed on RC structures of dierent dimensions in order to show that the decrease of natural frequency due to early age eects is more important in structures having a small thickness. In [18] authors modeled the dynamic behavior of a 28 story building of real size kept in either endogenous or non-endogenous conditions using a FEM approach. Only the non-endogenous building was both experimentally tested and simulated numerically, whereas the endogenous one (sealed one) was only modeled numerically.…”

Finite element analysis of RC beams subjected to non-uniform corrosion of steel bars

“…COM 3D is an analysis system that can reproduce the structural behavior of reinforced concrete structures considering cracking of concrete, generated stress and deformation of the member by using a nonlinear finite element method. The validity and reliability of the software can be found in the literature (Maekawa et al 2003;Chijiwa et al 2011;Chijiwa et al 2015;Uno et al 2017).…”