Material Traceability and Reusability in BC1: 2012

Transcription

1 Material Traceability and Reusability in BC1: 2012 by: CHIEW Sing-Ping Nanyang Technological University

2 Steel Selection & Quality Assurance BC1: Design Guide on Use of Alternative Steel Materials to BS5950 2

3 Current Revisions? In short: - new steel - new design code - reused steel Companion publication: - Handbook to BC1: 2012

4 Current Revisions of BC 1 Expanded title: BC 1: 2012 Design Guide on use of alternative structural steel to BS5950 and Eurocode 3 to cover expanded scope:- Additional material categories (Section 2) Specific provision to Clause 4.4 (Section 4) Design parameters to Eurocode 3 (Section 5) Material traceability & reusability for re-use steel (new Section 6 for struts and sheet piles) Update production standards, and hence the list of certified steel materials (Appendix A)

5 Updates in Section 2 Inclusion of 2 new material categories:- Hot-rolled steel bars round/flat/square bars up to grade 690/1000 based on EN 10058/59/60; Sheet piles hot-rolled sheet piles to JIS A5523 & EN 10248, cold-formed sheet piles to EN 10249; pipe piles & steel piles are already covered under hot-rolled sections and hollow sections. Important Note: Sheet piles to JIS A5528 not-certified (Grades SY295 and SY390), only Grades SYW295 and SYW390 to JIS A5523 are certified.

6 Updates in Section 4 Clause 4.4 Special Case is made more specific and clearer, i.e. the written plan should comprise at least one set of material testing for each batch/lot of steel materials (instead of 100% material testing )

7 Updates in Section 5 Inclusion of design recommendations to EN 1993 Simplification of design parameters tables for ASTM/AS steel materials* and bolts *Gradual downgrading of material strengths are applied to ASTM/AS steel materials as thickness increases Omission of bolt-nut-washer matching tables more appropriate to refer to the material standards Inclusion of GB/T 19879:2005 steels up to Q460, ASTM A1046:2007 profiled sheets, JSS II-09:1981 S10T torshear bolts & other materials deemed suitable

8 Section 6 NEW!!! (1) Addition of new section, i.e. Section 6. Material traceability and reusability Guidelines on the re-use of sheet piles & steel materials in steel strutting system used in ERSS Two important aspects:- Traceability Reusability

9 Section 6 NEW!!! (2) Material traceability The ability to trace back the source of a specific steel material to its original identity as delivered from the mill, through proper identification and quality assurance system Each piece of steel members to be marked with a unique ID for future reference to the FPC certificate, MTC, inspection record & test report

10 Section 6 NEW!!! (3) Traceability/Classification of ex-stock material Ex-stock materials delivered without FPC certificate for repeated use - delivered with manufacturer test certificate - certifiable & listed in Appendix A Key: Yes No Material testing for each batch/lot (see Appendix B) Mill has subsequently obtained FPC certificate? Correlated NDT for each member (see Appendix B) Batch/lot known? Material testing for each batch/lot (see Appendix B) Class 1 Class 2 Note: Ex-stock steel materials which do not fit into this flow chart shall be classified as Class 3

11 100% Correlated Non- Destructive Testing (NDT)? Correlation of mechanical properties to chemical composition using verified equations from database analysis a) Surface Polishing b) Test Gun c) Portable Computer Non-Destructive Testing using Portable Optical Emission Spectrometer (OES)

12 Section 6 NEW!!! (4) Material reusability The ability of the used steel materials to be reused & to perform adequately as anticipated in the design Good practices:- Apply permanent & systematic marking; Avoid mixing of steel grades; Apply corrosion protection coating

13 Section 6 NEW!!! (5) Reusability assessment 1. Surface condition 85% steel surface free of rust not severe than Grade C (per BS EN ISO ); Minor repair if necessary 2. Sectional dimensions Measured at 3 locations; Measured dimension nominal dimension allowable tolerance, or relegated to next lighter section

14 Section 6 NEW!!! (6) Reusability assessment 3. Shape & straightness To comply with BS ; Straightening treatment if necessary 4. Bolts & welded connections Visual inspection on used connections; Loosened/retrieved bolts not to be re-used 5. Interlock of sheet piles - Adequate free play to fit together and engaged in a such manner to transfer the in-service forces

15 Section 6 NEW!!! (7) Reusability assessment Used steel materials with unique/traceable identity Pass Quality test regime (see , , & ) Fail Re-use Economic feasibility of re-conditioning Yes Re-conditioning No Reject & scrap

16 Section 6 NEW!!! (8) Quality system Supplier/fabricator to implement a quality system:- Material marking & identification; Documentation of certificates/reports; Record of usage & reconditioning history; In-house inspection & quality test regimes The quality system shall be audited by an independent inspection body (IB) acceptable to BCA and accredited by SAC in the first instance, followed with subsequent surveillance audits at every 6 months

17 Updates in Appendix A All latest standards have been compared against the material performance requirements The lists have been updated, including two (2) new categories of materials, i.e. hot rolled steel bars & sheet piles* *Steel for cold forming is also accepted as certified materials for cold formed sheet piles

18 Summary (1) Latest revisions of BC 1 to cover extended scope & updated material standards:- Additional material categories steel bars & sheet piles Design recommendations to Eurocode 3 Material traceability & reusability for sheet piles & steel strutting system Update of the list of certified steel materials per latest material production standards Good for stockists/traders and steel specialist builders/suppliers to keep abreast of development

19 Summary (2) Companion handbook to BC1 covers: Design Procedures Design Parameters for Class 1, 2 & 3 Certified Steel Materials Non-Certified Steel Materials Reusability of Steel Materials3