In this study, the abnormal noise phenomenon generated intermittently in the shock absorber of the combat armored vehicle was approached from the side of the squeak joint to solve the phenomenon. In order to identify the cause of the noise, the factors causing friction in the shock absorber were checked from the viewpoint of problem product analysis, process, and design. As an improvement plan, by improving the non-lubricated section in the nitrogen chamber, the operating noise was reduced to a level lower than that of a general automobile engine along with the elimination of noise. Considering that this is a combat vehicle, it is judged that it has been improved so as not to affect the survivability and health of the crew during equipment operation. Through the improvement of this study, it is expected to prevent power loss and improve the emotional quality of our soldier.

This study introduces abnormal noise phenomenon of steel deck plate bridge which have not been mentioned in the literature or reports. The abnormal noise occurred from the time when the girder was installed and the welding was completed. And it had continued after the bridge opened. In this study, firstly, the characteristics of abnormal noise is analyzed. Also it presents the mechanism of noise generation.