Model updating‐based automated damage detection of concrete‐encased composite column‐beam connections

Abstract

Summary This paper presents a comparative study about the numerical and experimental system identification and model updating‐based automated damage detection of concrete‐encased composite column‐beam connections. Four different column‐beam connection types named as CBC#A, CBC#B, CBC#C, and CBC#D were considered without any changes in geometrical configuration. Numerical and experimental dynamic characteristics were extracted by initial finite element analysis and nondestructive experimental measurements for undamaged condition. Enhanced frequency domain decomposition (EFDD) method was used for experimental modal extractions. A good agreement was observed between experimental natural frequencies but not enough correlation between damping ratios for all connection types. Maximum differences between initial finite element and undamaged experimental results were calculated as 34.68% for CBC#A, 40.78% for CBC#B, 33.15% for CBC#C, and 47.13% for CBC#D type connection details. The differences were reduced to 0.24%, 0.24%, 0.16%, and 0.15%, respectively, by automated model updating procedure using spring coefficient, modulus of elasticity and weight per unit volume. In the case of the damaged condition, lateral forces were applied to simulate the effect of an earthquake. Cracks strongly affected the natural frequencies. The mode shapes were not broken evidently after damaged conditions. The mode shapes definitely deviated a bit, but generally the same after damages. The natural frequencies have decreased non‐monotonically due to the decrease in the rigidity of the column and beam at the cracked section. Maximum differences were calculated as 14.96% for CBC#A, 41.08% for CBC#B, 31.35% for CBC#C, and 45.93% for CBC#D type connection details. After automated model updating the above‐mentioned differences were reduced to 0.35%, 0.78%, 0.73%, and 0.85% respectively. Contour diagrams of changes of updating parameters were plotted for damage identification. The regions with high difference rates indicated the location of the damage.

A Review on Vibration-Based Damage Detection Methods for Civil Structures

“…When the damage in a concrete member is not obvious or difficult to quantify (e.g., some hidden defects after shock events), frequencybased FE model updating is a possible approach to localizing the damage. To model the damage in concrete-encased composite column-beam connections after an earthquake, Nasery et al [50] conducted a cyclic loading test on four samples with different connections (as shown in Figure 6a). Concrete failure and some welding damages can be observed after the loading test (see Figure 6b).…”

Integrating Image Processing and Machine Learning for the Non-Destructive Assessment of RC Beams Damage

“…This method involves manipulating the natural frequency of the structure and modeling the crack using a torsional spring, allowing for precise crack assessment. Nasery et al [7] proposed an approach for automated damage detection in concrete-encased composite column-beam connections using model updating techniques. Their findings demonstrated that their proposed method identified the location and severity of the damage.…”

Experimental study on the seismic behavior of large‐size square and rectangular steel reinforced concrete columns with high and normal strength concrete

“…Hwang et al [ 13 ] proposed a type of prefabricated SRC columns reinforced by angle steel and analyzed the influences of steel ratios, stirrup spacings and prefabrication details on the axial compressive behavior and seismic behavior. Nasery et al [ 14–17 ] conducted a series of investigations of concrete encased composite column‐beam connections. It was first ever research to investigate the changes in dynamic characteristic of the encased steel profile column‐beam connections before and after lateral cyclic loading test by adopting preambient vibration measurements.…”