Undercrossing tunnels are frequently constructed by the shield-driven method in metro projects.Shield tunneling affects the existing tunnel inevitably.
The causes of the front fog lamp shield blistering after surface treatment are studied by means of metalloscopy,scanning electronic microscope and energy spectrum analysis.
The video also revealed a previously undescribed feature of these fish — its eyes are surrounded by a transparent, fluid-filled shield that covers the top of the fish's head.