Strength and stiffness estimation of damaged reinforced concrete shear walls using crack patterns

Abstract

Summary The purpose of this paper is to estimate the stiffness and strength of damaged rectangular reinforced concrete shear walls after an earthquake using surface crack patterns. Assessing the damage severity of buildings after an earthquake is an important part of the emergency inspection operation of buildings. Expert inspectors tag buildings into two categories of safe or unsafe that are usually affected by subjective decisions, which may result in catastrophic events reported in previous earthquakes. In this research, an extensive database on the images of damaged rectangular reinforced concrete shear walls (RCSWs) is collected and used to develop predictive equations for updated stiffness and strength of damaged walls. Based on the crack patterns extracted from images of the shear walls in different loading states, empirical relationships for predicting reserved strength and stiffness of damaged RCSWs are proposed. These equations are developed based on the fractal quantities of surface crack patterns and structural data for various possible scenarios using symbolic and Bayesian regression. Finally, a damage index is proposed based on the crack pattern of RCSWs that can be used for automated post‐earthquake evaluation of buildings.

Durability health monitoring during construction of concrete structures in marine environment

“…In‐service concrete structures need to be evaluated by inspection of their different structural elements to determine their durability or remaining service life (if external deterioration is present). Methodologies have been developed in different countries to estimate the structure's health, mainly bridges, through inspection 4–6 . But scarce can be found related to durability performance 7,8 .…”

Post‐earthquake damage evaluation of non‐ductile RC moment frames using surface crack patterns

“…Such procedure has been followed in the previous studies for obtaining the fractal dimensions. 33,34,[36][37][38][39][40][63][64][65][66][67][68] To this end, a scaling factor of 20 pixels for 1 cm was considered, and the cracks were digitized using a line with a one pixel thickness. Noteworthy to mention that according to Equation 2, the scaling factor of centimeter to pixels used for regenerating the images does not affect the multifractal dimensions values.…”

Smart monitoring of strengthened beams made of ultrahigh performance concrete using integrated and nonintegrated acoustic emission approach

“…NDT based on vibration methods, imaging techniques, and nonlinear ultrasonic testing has been successfully applied to monitor deep foundation piles, 7 diagnose nonlinear effects in aircraft engines, 8 understand the behavior of transmission line conductors in field conditions by evaluating natural frequencies, 9 detect damage in fiber‐reinforced polymer‐bonded structures, 10 and describe modulated sidebands in metallic and carbon fiber‐reinforced polymer specimens 11 . A combination of SDT and NDT is also integrated in numerous research to study collapse mechanisms of wood masonry heritage buildings, 12 predict strength and stiffness of reinforced concrete shear walls, 13 and estimate moisture content in brick wall 14 …”