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






2. Ups set time






3. makes it mushier because cement grains more distributed






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






5. Trapped air - reduces strength - ups permeabiity






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






7. Normal- for general work






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






9. By vibrating - otherwise rock pockets occure -






10. Crush clinker into super fine powder






11. Early stength at faster rate - for cold temps






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






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






14. For early strength gain






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






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






17. Source of hotgases - biggest piece of moving equipment






18. Good stability






19. Sometimes worse






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






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






22. To improve workability for fresh concrete






23. Nonpotable/potable >90% - the acceptable






24. Cement+water






25. Water beyond SSD condition






26. Stop and reactivate hydration process






27. To increase stability of materials - reduce rutting






28. Low stability






29. Distributes cement grains - cement becomes more mushy -






30. High sulfate resistence -






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






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






33. B/c of trucks over time






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






35. Water used for hydration - water beyond SSD - min- .22-.25 - typical- .4-.5 (.44) - lower WC ratio = more strength -






36. Cement paste has bulk SG< cement particles






37. Bending moment - no shear in middle third






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






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






40. Heat and pressure ex- marble - quaertzile






41. Cement+course aggregate






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






43. From chemicals or excessive drying






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






45. 94 lbs






46. Heavy traffic






47. Cement+sand






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






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






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