Concrete fundamentals
Download
1 / 15

Concrete: Fundamentals - PowerPoint PPT Presentation


  • 157 Views
  • Uploaded on

Concrete: Fundamentals. Prepared by: Marcia C. Belcher Construction Engineering Technology. Common Uses. Slabs (roadways, bridges, airstrips) Beams & Columns Parapets (highways) Piers (structures, bridges) Pipe Foundations (large and small) Retaining Structures (dams).

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about ' Concrete: Fundamentals' - maddox


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.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
Concrete fundamentals

Concrete: Fundamentals

Prepared by:

Marcia C. Belcher

Construction Engineering Technology


Common uses
Common Uses

  • Slabs (roadways, bridges, airstrips)

  • Beams & Columns

  • Parapets (highways)

  • Piers (structures, bridges)

  • Pipe

  • Foundations (large and small)

  • Retaining Structures (dams)


Special needs of concrete
Special Needs of Concrete

  • Exposure & use conditions require attention in mix design.

    • Marine environment

    • De-icing salt exposure

    • Freeze-thaw

    • Hi sulfate exposure

    • Early use of structure (bridge decks)

    • Very thick pours (homogenous pours like earth dams & parapets)

    • Very slender elements (pipe)


What can we do to modify concrete design
What Can We Do To Modify Concrete Design

  • Add plasticizers to increase workability

  • Use larger aggregates to increase strength

  • Reduce W/C ratio to increase strength

  • Use air entrainment to improve durability

  • Use pozzolans to improve chloride resistance

  • Use “accelerators” increase cure rate for hi early strength

  • Use set retarders or fly ash to decrease internal temperature & reduce shrinkage cracking


Portland cement types
Portland Cement Types

  • The ingredients in the Portland cement can be modified to produce various properties.

  • These are called “Types”


Portland cement types type i
Portland Cement Types – Type I

  • General Purpose

  • Most commonly used

  • No special curing, setting or resistance characteristics

  • Suitable where no special properties are required


Type ii
Type II

  • Type II cement contains no more than 8% tricalcium aluminate (C3A) for moderate sulfate resistance.

  • Increases resistance to sulfate attack over Type I

  • Lower heat of hydration

  • Used for mass pours such as bridge piers

  • Used where ground water contains high sulfate levels


Type iii high early strength
Type III – High Early Strength

  • Similar to Type I cements except it is ground finer

  • This increased hydration rate.

  • Results in rapid curing & higher early strengths.

  • Results in higher heat of hydration

  • Used in cold weather concreting

  • Used when early strength is required


Type iv
Type IV

  • Hi levels of dicalcium silicate and tetracalcium aluminoferrite

  • Used in massive concrete structures where heat generated from hydration must be minimized.

  • Low heat of hydration = slow strength development

  • Used for mass pours such as dams where shrinkage problems may occur


Type ia iia iiia iva
Type IA, IIA, IIIA, IVA

  • “A” implies that air entraining is added to the portland cement







ad