Double Crack Damage Identification of Welded Steel Structure Based on LAMB WAVES of S0 Mode

Abstract

Steel structures are widely used in large-span bridges, offshore platforms, mining equipment and other large-scale buildings. The damage of steel structures will cause significant safety risks in a project. Therefore, it is of great significance to identify and study damage to steel structures. In this study, the propagation of Lamb waves in a steel plate with double cracks is simulated. Using finite element analysis and experimental study, damage identification and damage imaging of double crack damage to a steel plate are performed, and the numerical simulation results are in good agreement with the experimental results. Considering the reflection and transmission of Lamb waves at the welding seam, the location and imaging of crack damage in a welded steel plate are also studied. The imaging results obtained from simulation and experiment show high level in accuracy. By comparing the amplitude of the signal in the propagation process, it is concluded that the transmission energy at the weld seam decreases.

Theoretical and Numerical Study of Eddy Current Pulsed Thermography to Detect Damage of Deep-Sea Manned Pressure Hull

“…Guan et al [5] monitored the health of submarine pipelines via acoustic waves, formed a mobile mapping system using onboard sensors and underwater probes to extract a route, and buried depth information from acoustic images to monitor the status of the pipelines. Hu et al [6] derived the Lamb wave equation according to the relevant theory and used the reflection and transmission of the Lamb wave at the crack to study the location and imaging of the crack damage in the welded steel plate. (3) Health monitoring is based on the principle of optical signals.…”

“…Guan et al [5] monitored the health of submarine pipelines tic waves, formed a mobile mapping system using onboard sensors and u probes to extract a route, and buried depth information from acoustic images the status of the pipelines. Hu et al [6] derived the Lamb wave equation accor relevant theory and used the reflection and transmission of the Lamb wave at t study the location and imaging of the crack damage in the welded steel plate However, the damage identification and quantitative evaluation methods of pressure hulls have not been studied. Pulsed eddy current thermal imaging detection technology is an active infrared thermal imaging method that uses high-frequency alternating current to generate eddy currents on the surface of the specimen.…”