Test your basic knowledge |

Civil Engineering Materials

Subject : engineering
Instructions:
  • Answer 50 questions in 15 minutes.
  • If you are not ready to take this test, you can study here.
  • Match each statement with the correct term.
  • Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.
1. Water used for hydration - water beyond SSD - min- .22-.25 - typical- .4-.5 (.44) - lower WC ratio = more strength -






2. Sometimes worse






3. Stop and reactivate hydration process






4. Cement+water






5. Ups capilary voids - lowers strength






6. From chemicals or excessive drying






7. Sum of cumul % retained / 100 - higher= bigger particle sizes= smaller amount of agg needed






8. Intentional well distributed air - up durability - adds strength






9. 94 lbs






10. Tricalcium silicate (C3S) - dicdalcium silicate (C2S) - tricalcium aluminate (C3A) - tetracalcium aluminoferrite (C4AF)






11. By vibrating - otherwise rock pockets occure -






12. Distributes cement grains - cement becomes more mushy -






13. Stratified structure - disintegrated exitisting rocks - inorganice remains of marine animals - ex- limestone






14. Do NOT dump in separate piles - deposit in large piles -






15. Normal- for general work






16. makes it mushier because cement grains more distributed






17. Bending moment - no shear in middle third






18. Freeze-thaw cycles - bad curing or too much water






19. Water beyond SSD condition






20. Delay initial set - for long hauls or unusual placement






21. Air bubbles for sapce for water to expand when freezes






22. Ups set time






23. Low Heat of Hydration- for careful control of heat - dams






24. Low stability






25. Ponding/immersion - spraying/fogging - wet coverings -impervious papers/plastic sheets - membrane forming - steam - insulating blankets/covers - electric/hot oil/ infrared -






26. Consolidation - strike off - depress agg - darby or bull float - (TIME) - edging - jointing - floating - (TIME) - texturing - curing






27. B/c of trucks over time






28. For continued hydration and strength gains - otherwise only 50% strength gained - ups durability and abrasion resistance - prevent shrinkage cracking -






29. High Early Strength- fast track projects - we want low set time






30. Slow down rate of aluminate hydration -produces sulfate ions - flash set - false set in excess - higher rate of C-S-H (strength)






31. Heat and pressure ex- marble - quaertzile






32. Heavy traffic






33. Space between layers in CSH - water in interparticle space held by hydrogen bonds






34. Corner was hotter on top than bottom - it warped and lifted - pressure makes corner crack -






35. For early strength gain






36. Volcanic - hardening and crystal molten material ex- granite






37. Trapped air - reduces strength - ups permeabiity






38. Cement+course aggregate






39. max is 12 in - more free water= more slump






40. Moderate Sulfate Resistance- large piers






41. Crush clinker into super fine powder






42. misplaced joints - more specific- spalling- breaking away of edges






43. Source of hotgases - biggest piece of moving equipment






44. Near surface water is cause






45. Trim subgrade - moisten subgrade - compact (use vibratory roller) - do NOT deposit frozen subgrade or disturb it - uniform - NO water added in front of paver -






46. High sulfate resistence -






47. Calcareous (calcium) - argillaceous (aluminum) - iron oxide (iron) - gypsum (silicon)






48. Good stability






49. Loss of water from paste (evap) - 1% vol lowers - cracking - prevent by water loss control -






50. Greater =less free water needed to get a given slump