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Findings from On-site I nspection ( Rt 202/US Rt 23 BRIDGE ). On Tuesday, June 14 Masato Matsumoto Executive Vice President NEXCO-West USA, Inc. Expressways in Japan. East NEXCO. Central NEXCO. West NEXCO. Metropolitan EXPWY Co. Japan Bridge Co. Hanshin EXPWY Co. 2.
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Findings fromOn-site Inspection(Rt 202/US Rt 23 BRIDGE) On Tuesday, June 14 Masato MatsumotoExecutive Vice President NEXCO-WestUSA, Inc.
Expressways in Japan East NEXCO Central NEXCO West NEXCO Metropolitan EXPWY Co. Japan Bridge Co. Hanshin EXPWY Co. 2
Deterioration of Concrete Structures in Japan 【Environmental factors】 - Chloride induced deterioration - Carbonation 【External forces (e.g. traffic load)】 - Fatigue for reinforced concrete deck slabs - Fatigue for steel bridges 3
Deteriorated Bridges in Japan Chloride Induced Deterioration Fatigue of RC Deck Slab 4
Highway Inspection (NEXCO Toll Roads) Note: Frequency Depends on Traffic Volume 5
Routine Inspection RoutineInspection (from the vehicle) RoutineInspection (on foot) 6
Definition of Bridge Condition US (NBIS) NEXCO Note: If the damage can cause hazards to traffic or third party, additional ‘E’ is attached to the condition states. 8
Notes from Visual Inspection W:1.50m x L:0.10mLower Flange Displacement - B Decline of Steel Bearing 2 Loose Boltsfor Steel Bearing Decline of Steel BearingTouching the Stopper Displacement – A3 11
Bridge Name, Location, etc. Area Damage Location Condition State Recommendation Counter Action Repaired Date Damage Description Date Weather Inspector etc. Notes from Visual Inspection 12
Recommendations (Crack in P1) Condition State【A1】 W:1.20m x L:0.20mP1 Lateral BeamRebar Exposure W:0.70m x L:0.20mP1 Lateral BeamRebar Exposure ①-1 Condition State【A1】 14 ②-1 ①-2
Recommendations (Bearings on P2) Condition State【B】 Displacement - B Decline of Steel Bearing Decline of Steel Bearing, Touching Stopper ③-1 Condition State【A3】 ④-1 15 ④-2
Recommendations (Bearings on P2) • The movable bearing has the functionality of moving and rotation. There are stoppers near the movable bearing to restrict the movement. • The above stoppers has been in the compressed status. • Counteraction should be considered if the displacement is active. 16
Recommendations (Spalling over P2) Condition State【A1】 ⑤-1 W:0.80m x L:0.20mOverhang Slab Sound Concrete Spalled Area 18 ⑤-2 ⑤-3
Recommendations (Spalling over P2) • Rebar corrosion at the end of the slab concrete, due to the water leakage from expansion joint. • Waterproof of expansion joint is recommended. • Anticorrosive countermeasures for rebar and replacement of the cover concrete should be scheduled. 19
Recommendations (Delamination) Condition State【A2】 W:0.30m x L:0.20m ⑥-1 Condition State【A1】 W:1.80m x L:0.30m ⑦-1 20
25000 pix Crack Detection by Image Processing Technology Rt 202/US Rt 23 BRIDGE 1pix=1mm 0.5mm crack can be identified. 100 millon pix 460 MB/TIF 4000 pix 21
・Recognize the crack by Photoshop CS4. ・The crack width can be identified using special" crack detection engine". ・Crack width is detected approximately based on the width corresponding to 1 pix in the photos. Width legend--: <0.5mm --: 0.5mm~0.7mm --: >0.7mm 22
1.6mm 0.2mm 1.4mm 800mm Image of the crack in Abutment A1; Photos taken from 22 meters away; The practical resolution can be expected to reach 0.1mm/pix. 23
Results of Infrared Technology Re-deterioration Repaired Area (Drain Hole) (Drain Hole) KEY WEST MIAMI P46 P47 Gulfside Oceanside