1 / 30

SPECIFYING MANUFACTURED SANDS FOR CONCRETE APPLICATIONS

SPECIFYING MANUFACTURED SANDS FOR CONCRETE APPLICATIONS. Vute Sirivivatnanon Associate Professor of Construction Materials University of Western Sydney Ion Dumitru Chairman – Manufactured Sands Research Steering Committee Cement Concrete & Aggregate Australia. CONTENTS.

lloyd
Download Presentation

SPECIFYING MANUFACTURED SANDS FOR CONCRETE APPLICATIONS

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. SPECIFYING MANUFACTURED SANDS FOR CONCRETE APPLICATIONS Vute Sirivivatnanon Associate Professor of Construction Materials University of Western Sydney Ion Dumitru Chairman – Manufactured Sands Research Steering Committee Cement Concrete & Aggregate Australia

  2. CONTENTS • Sustainability measures in construction materials • Optimum use of natural & manufactured sands • Important sand characteristics to all concrete • Important sand characteristics to concrete pavement • CCAA/RMS collaborative study • Performance-based specifications 2

  3. SUSTAINABILITY MEASURES INCONSTRUCTION MATERIALS 3

  4. OPTIMUM USE OF SANDSNATURAL SAND Recovered from geologically recent deposits such as • Morton Bay, • Kurnell dunes, and • Nepean River flood plain Excellent fine aggregate from geological processes of shaping and sorting resulting in • Rounded to sub-rounded and smooth surface • Removal of weaker minerals 4

  5. OPTIMUM USE OF SANDS MANUFACTURED SAND Suitable source rock purpose-made throu • Crushing, • Screening (sizing & blending), and • possible washing to control microfines ≠crusher dusts as blend component in road bases, fills, fines, and stabilized crusher fill. 5

  6. IMPORTANT CHARACTERISTICS TOALLCONCRETE GRADING, SHAPE & TEXTURE, FREE OF DELETERIOUS FINES, DURABLE & NON REACTIVE, GOOD SKID RESISTANCE The challenge is to apply engineering knowledge to the best & economical use of manufactured sands through appropriate specifications 6

  7. IMPORTANT CHARACTERISTICSTO ALL CONCRETE 7

  8. IMPORTANT CHARACTERISTICSTO ALL CONCRETE 8

  9. IMPORTANT CHARACTERISTICSTO CONCRETE PAVEMENT Concrete pavement must be fit for purpose • Resistance to wear (abrasion of texture) • Good skid resistance in wet and dry condition Skid resistance depends on the complementary functions of macro- & microtexture • Microtexture: λ< 0.5mm • Macrotexture: 0.5<λ< 50mm 9

  10. MACROTEXTUREIN SKID & ABRASION RESISTANCE MACROTEXTURE Weller and Maynard (1970) • Tyned grooves provide drainage to prevent hydroplanning • Mechanical resistance to skiding Shackelet al.,(1994) • Dependent on mix & curing ICAR Barborak and Rached, (2010) • Effect of textures & travel speed on skid (friction) S Bulahdelah Mittagong Bypass 10

  11. Effect of textures on skidICAR Barborak and Rached, (2010) Tined+Carpet Broom Finish Carpet Drag Smooth Grass 11

  12. Mineralogical compositions Silica Content MAN SAND TESTING Micro-Deval - abrasion Na2SO4 Soundness - stability Absorption – stability MBV x Passing 75-micron - durability Historical perspective Source Rocks ▼ Coarse Aggregates ▼ Man Sands Micro-Deval Apsortion LAB CONCRETE TESTING Skid before & after wear Wear loss (AS 1141.41) Abrasion loss (AS 4456.9) Performance Criteria Lab-prepared Concrete Specimens Natural Sand FIELD ASSESSMENTS SCRIMS and other by Road Authority Field-retrieved Concrete specimens Figure 1 EFFECT OF SAND ON MICROTEXTURESKID & ABRASION RESISTANCE 12

  13. MANUFACTURING & TESTING OF CONCRETE3 Natural sands and9 Manufactured sands at 50% & 80% of total fine 13

  14. Sand durability tests • Micro-Deval • % abrasion in water • Sodium Soundness • stability due to expansive salt crystallization • Absorption • Porosity • Free Silica Content • Petrography • Chemical 14

  15. RMS Collaboration - Tarcutta Range test site 15 Truck Rest Test site is on the S/B, opposite the entrance to the Truck Bay To Wagga Wagga 2820

  16. Skid of various surfaces from lab-prepared & field sampled Tynedsurface Field sample skid after wear of workmanship-independentsurfaces Sawn surface Lab sample Off-form surface 16

  17. Pendulum friction test (AS 1141.42)Friction Value FV 17

  18. PAFV abrasion resistance (AS 1141.41)33-35 revs/min (8,000&16,000 cycles after 4 & 8 hours) 2-hr with coarse abrasion [Balck silicon carbide No. 320 @ 2g/min] 2-hr with fine abrasion [Optical emery No. 600 @ 2g/min] 18

  19. Abrasion index (AS 4456.9)4 circular faces subjected to 600 steel balls60 rev/min x 1 hr = 3600 cycles 19

  20. Skid (friction) after abrasion by PAFVof off-form concrete Intrinsic Skid 20

  21. Skid (friction) after abrasion by PAFVof saw-cut concrete

  22. “Characteristic skid resistance ”Common skid resistance of off-form & saw-cut surfaces after 4-5 hrs of polishing Characteristic skid 22

  23. Relating skid resistanceof various surfaces Lab-prepared concrete Field-sampled concrete SCRIM Intrinsic Skid Characteristic Skid Resistance Sand properties Off-form 8-hours polishing Off-form 4-hours polishing Saw-cut 4-hour polishing Saw-cut 4-hour polishing Tyned 23

  24. Skid after wear of concrete with various sands SCRIM results: Mittagong 68, 71 Tarcutta 74, 68 24

  25. Intrinsic Skid and micro-Deval or free silica content of Sands 83% Corr 25

  26. Fowler and Rached, ‘Evaluation of the Polish Resistance of Fine Aggregates in PCC Pavements’,( to be published in TRR) 26

  27. Abrasion is largely a function of strengthand independent of type of sand 65% Corr 27

  28. Possible performance-based specifications for concrete pavement NATURAL & MANUFACTURED SANDS • Micro-deval≤15% for skid after wear or CONCRETE PAVEMENT (LAB) • Characteristic skid > 50 for off-form surface • A nominated concrete strength for abrasion resistance (independent of sand used) 28

  29. CONCLUSIONS CCAA research has lead to • Abetter understanding of how to specify fit-for-purposemanufactured sands for all concrete applications. Specifications are introduced into AS 2758.1 (2012) • Critical property of sands to concrete pavements is durability (Micro-Deval) for skid after wear& concrete strength for abrasion resistance • Important properties to concrete producer are shape, surface texture & consistent grading. 29

  30. CCAA PUBLICATIONS ON MANUFACTURED SAND Manufactured Sand – National test methods and specification valueshttp://www.concrete.net.au/publications/pdf/ManSand.pdf Guide to the Specification and Use of Manufactured Sand in Concrete http://www.concrete.net.au/publications/pdf/GuideManSand.pdf Manufactured Sand - Abrasion resistance and effect of manufactured sand on concrete mortarhttp://www.concrete.net.au/publications/pdf/ManuSandReport2.pdf Effect of manufactured sands on surface properties of concrete pavement (to be available on CCAA website shortly) 30

More Related