SIAMA. SIAMA Asset Management Technologies Level-2 Bridge Condition Inspection

Transcription

1 Prolonging Infrastructure Assets Life Asset Management Technologies Level-2 Bridge Condition Inspection

2 CONTENTS Background of Bridge Condition Inspection Purpose of inspection Examples of Defects External causes of deterioration Australia Bridge Inspection Standard Level-2 Bridge Condition Assessment Condition Rating Comparison Limitation 2

3 Why should we regularly inspect bridges? 3

4 Why should we regularly inspect bridges? Collapse of the Silver Bridge Ohio, USA Collapsed in people death The first National Bridge Inspection Standards (NBIS) were developed in

5 Purpose of Inspections Keep the performance of bridge under acceptable condition Function Capacity Strength Durability 5

6 Material Defects Deterioration Mechanisms Types of deterioration mechanisms Concrete Steel Timber Other Corrosion of reinforcement Carbonation Alkali-Silica Reaction (ASR) Cracking Spalling Surface defects Delamination Corrosion Permanent deformations Cracking Loose connection Fungi Termites Marine organisms Corrosion of fasteners Shrinkage and splitting Fire Weathering Cracking Splitting, spalling and disintegration Loss of mortar and stones 6

7 Example of Defect - Concrete Reinforcement Corrosion 7

8 Example of Defect - Concrete Alkali-Silica Reaction 8

9 Example of Defect - Concrete Cracking 9

10 Example of Defect - Concrete Spalling 10

11 Example of Defect - Steel Corrosion 11

12 Example of Defect - Steel Cracking 12

13 External Causes of Deterioration 13

14 Element Level Bridge Inspection Component vs Element: (US) Component Deck, Super-, Sub-structure. General condition rating Element Bearing, Pier cap, Abutment etc. Detailed condition description Quantified data for all elements Each element Descriptions (Material type; Unit of measurement; quantity with CS) Condition state definition 14

15 Australia Bridge Inspection Standard 1 Routine visual inspection for maintenance issues and possible further inspection 2 Routine visual inspection to assess the condition rating of the structure and its components 3 Detailed engineering inspection to further identify and evaluate deteriorations 15

16 What is Level-2 Bridge Condition Inspection? 16

17 Objective of Bridge Condition Inspections Identify and quantify defects in the structure or its individual components, and determining maintenance needs or other actions Estimate budget requirements for MR&R (Maintenance, Repair and Rehabilitation) Determine residual life of structure Re-rate the structure after significant MR&R have been carried out 17

18 Levels of Analysis in Bridge Inspections Element-level Project-level Network-level BRD#5 BRD#6 BRD#7 BRD#8 BRD#1 BRD#3 BRD#9 BRD#4 BRD#2 18

19 Level-2 Bridge Inspection Condition Ratings CS1 CS2 CS3 CS4 CS5 19

20 Background of Level-2 Bridge Inspection Group Code Components found in Group Approach AP1 or AP2 AP, GR, K, FY, WS Abutment A1 or A2 A, ABS, B, PRO, H, P, PED, COR Pier P1, P2, P3 etc. B, CAP, COR, H, J, P, PED, WAL Spans S1, S2, S3 etc. BR, D, FY, G, K, XG, WS Code Meaning Unit A Abutment Each AC Arch Culvert Lin m ABS Abutment Sheeting m2 AP Approach Each B Bearing Each Code Meaning Unit C Column Each CAP Pilecap Each COR Corbel Each D Deck Each F Footing Lin m Code Meaning Unit FY Footway Lin m G Girder Each GR Guardrail Each H Headstock Each J Joint Lin m 20

21 Example: data collected from Level 2 bridge inspection 21

22 Background of Level-2 Bridge Inspection Approach 1 (AP1) Span 1 (S1) Span 2 (S2) Span 3 (S4) Approach 2 (AP2) Footway Superstructure Abutment 1 (A1) Pier 1 (P1) Pier 2 (P2) Abutment 2 (A2) Substructure 22

23 Inspection Procedures Typical Level 2 Bridge Inspection Procedures & 5 Pre-site visit Confirmation of required resources Perform condition assessment Preliminary/final inspection report The qualified inspector will conduct a inspection. The inspector will evaluate a condition rating for each individual structural element based on the standard Level 2 Inspection procedure. 23

24 Inspection Procedures (Step 1) Step 1: Pre-site visit Risk management Inaccessibility Dangerous places Hazardous environments 24

25 Inspection Procedures (Step 2) Step 2: Confirmation of required resources PPE Bridge under inspection unit Traffic controller etc. 25

26 Inspection Procedures (Step 3) Step 3: Condition assessment Concrete 26

27 Inspection Procedures (Step 3) Steel 27

28 Inspection Procedures (Step 3) Timber

29 Inspection Procedures (Step 4 & 5) Step 4 & 5: Preliminary / final inspection report Condition Inspection Report Defective Components Report Standard Procedure Exceptions Report Photographic and Sketches Record Report examples 29

30 Limitation of Level-2 Bridge Inspection Although current routine bridge inspections are required to be carried out by certified inspectors, some major issues have been identified: Visual inspections are subjective and not always reliable The manual inspection process is time-consuming and costly A number of safety risks are associated with bridge inspectors 30

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