Damage identification of a belt conveyor support structure based on cross‐sectional vibration characteristics

Abstract

Belt conveyors, widely used in various industries worldwide, are often exposed to corrosive environment. Decades after construction, many of the support structures of belt conveyors have severe degradation, which may cause structural failure and functional stop of associated industries. To ensure the safety and reliability, effective and efficient damage identification of belt conveyor support structures is essential. However, application of existing global vibration-based damage identification techniques to these structures is difficult due to unavailability of baseline condition, the possible presence of multiple corroded members in a single structure, and the effect of nonstructural components that are occasionally updated. In this paper, a damage identification method of the main members of a belt conveyor support structure is proposed and validated through numerical and experimental studies. Cross-sectional modes (CSMs), shown to exist on the main member numerically and experimentally, are utilized. Eigenvalue analysis of an FE model of the support structure reveals the characteristics of CSMs and localized CSMs (LCSMs). A damage identification method based on these modes is developed; the existence and location of the damage is evaluated from current state of the structure without the need for before-after comparison. By identifying the distinct LCSMs, multiple damages are also independently identified.

Nonlinear model updating of a reinforced concrete pedestrian cable‐stayed bridge

“…in which K i is the current unloading stiffness, as shown in Figure 5a; K 0 is the initial linear unloading stiffness as shown in Figure 5a; and the damage index δ i can be obtained by Equation 13.…”

“…where σ maxi is the current envelop maximum stress shown in Figure 5b; σ max0 is the initial envelop maximum stress as shown in Figure 5b; and the damage index δ i can be obtained by Equation 13. The reduction in strength that is observed on reloading is modeled by employing the damage index to decide an increase in the maximum historic strain (decrease in the minimum).…”

“…in which ε maxi is the current strain that decides the end of the reload cycle for increasing strain demand, as shown in Figure 5c; ε max0 is the maximum historic strain demand, as shown in Figure 5c; and the damage index δ i can be obtained by Equation 13. In summary, the degradation of the reinforcing steel caused by previous unknown earthquake events can be accomplished by reconstructing the envelop curve.…”

“…Although these methods appear to be adequate for locating and quantifying damage when significant damage is induced in the structure, they are not sufficient for updating the parameters that govern nonlinear behavior of RC structures. [10][11][12][13] Therefore, these methods are not appropriate for determining future performance of the structure. In this regard, Zhang and Guo combined the proper orthogonal decomposition with a design of experiments to update nonlinear material parameters based on strain measurements with uncertainty consideration.…”

Novel Fault Diagnosis of a Conveyor Belt Mis-Tracking via Motor Current Signature Analysis

“…[ 1 , 2 ] and Refs. [ 3 , 4 , 5 , 6 ] via vibration analysis. The wavelet transform was used to decompose the signals for diagnosis, such as in Refs.…”