Structure damage
New damage is emerging due to weathering and deterioration of the ground material, such as damage to steel materials in bridges and deterioration of ground anchors in the cut slopes and deterioration of the inside of tunnels, which have not been clarified until now.
Current status of bridge damage
Significant damage has occurred due to the severe environment of use such as the deterioration over time, the fatigue of heavy vehicle traffic, and the effects of salt damage. In particular, regarding reinforced concrete floor slabs, damage such as sedimentation of concrete on the top of the slab, corrosion of rebar, and peeling of concrete on the bottom of the slab has become apparent.
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Deformation of floor slab upper surface: Sedimentation of concrete, corrosion of rebar -
Deformation of floor slab bottom surface: Corrosion of reinforcing bars and peeling of concrete
Current status of tunnel damage
Damages such as road surface upheavals and lining cracks due to soil strength around the tunnel due to weathering and deterioration of the ground around the tunnel due to underground spring water and groundwater and increase in earth pressure around the tunnel due to water expansion .. In particular, the occurrence of damage is becoming apparent in rock types in which natural rocks show a decrease in strength and expansive rock types in the long term.
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Cracks caused by road upheaval -
Step due to road bump
Current status of damage to earth structures (ground anchors)
Damage to embankments and cuts due to rainfall, deterioration of embankment materials, and damage to ground anchors designed and constructed according to the old standards. The old type anchor, which was constructed according to the old standard with low anticorrosion performance, is being damaged due to deterioration due to corrosion.
Bridge inspection
In addition to inspections by close-up visual inspection, palpation, and tapping, non-destructive inspections are also carried out as necessary. Based on the inspection results, we grasp the soundness and deformation of the structure and select repair / reinforcement measures against the deformation.
Tunnel inspection
Using inspection results of CCD cameras and surface images of tunnel linings, the inspection points are narrowed down by tapping sound.