Chap 09 Proportioning

Chap 09 Proportioning - Designing and Proportioning Normal...

Info iconThis preview shows pages 1–14. Sign up to view the full content.

View Full Document Right Arrow Icon
Designing and Proportioning Normal Concrete Mixtures
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Proportioning Factors in the Proportioning of Quality Concrete Mixtures Workability Durability Strength Appearance Economy
Background image of page 2
Proportioning Material s Cement Supplementary Cementing Materials Water Aggregate Admixtures Fibers
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Proportioning
Background image of page 4
Proportioning Mix Characteristics Strength Water-cementing materials ratio Aggregate size and volume Air content Slump and workability Water content Cementing materials content and type Admixtures
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Proportioning Requirements for Exposure Conditions Exposure condition Maximum w/ c-ratio by mass Min. strength, f' c , MPa (psi) No freeze-thaw, deicers, aggressive substances Select for strength, workability, and finishing needs Select for structural requirements Concrete with low permea- bility; exposed to water 0.50 28 (4000) Concrete exposed to freezing and thawing in a moist condition or deicers 0.45 31 (4500) For corrosion protection for 0.40 35 (5000)
Background image of page 6
Proportioning Requirement for Concrete Exposed to Sulfates Sulfate exposur e Sulfate (SO 4 ) in soil, % by mass Sulfate (SO 4 ) in water, ppm Cement type Maximu m w/c- ratio, by mass Minimum strength, f' c , MPa (psi) Negligible Less than 0.10 Less than 150 No special type required Moderate 0.10 to 0.20 150 to 1500 II, MS, IP(MS), IS(MS), P(MS), I(PM) (MS), I(SM) (MS) 0.50 28 (4000) Severe 0.20 to 2.00 1500 to 10,000 V, HS 0.45 31 (4500) Very Over Over V, HS 0.40 35 (5000)
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Relationship between W/C-Ratio and Strength Compressi ve strength at 28 days, psi Water-cementitious materials ratio by mass Non-air- entrained concrete Air-entrained concrete 7000 0.33 6000 0.41 0.32 5000 0.48 0.40 4000 0.57 0.48 3000 0.68 0.59 2000 0.82 0.74 Inch-Pound Inch-Pound
Background image of page 8
Proportioning Compressive Strength Vs. W/C- Ratio
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Bulk Volume of Coarse Aggregate Maximum size of aggregate, mm (in.) Fineness modulus of sand 2.40 2.60 2.80 3.00 9.5 (3/8) 0.50 0.48 0.46 0.44 12.5 (1/2) 0.59 0.57 0.55 0.53 19 (3/4) 0.66 0.64 0.62 0.60 25 (1) 0.71 0.69 0.67 0.65 37.5 (1 1/2) 0.75 0.73 0.71 0.69 50 (2) 0.78 0.76 0.74 0.72
Background image of page 10
Proportioning Bulk Volume of Coarse Aggregate
Background image of page 11

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Proportioning Absolute Volume of Coarse Aggregate per yd 3 of Concrete 1 yd3 0.46 yd3 Given:0.46 yd 3 of coarse aggregate Bulk density = 98 lb/ft 3 , rodded Relative density = 2.65 Water = 62.4 lb/ft 3 0.46 • 27 = 12.4 ft 3 12.4 • 98 = 1215 lb Absolute volume = 1215/(2.65 • 62.4) = 7.35 7.35/27 = 0.27 So the coarse aggregate is 27% of the absolute volume of the concrete
Background image of page 12
Proportioning Air Content and Aggregate Size
Background image of page 13

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 14
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 12/15/2011 for the course CM 217 taught by Professor Rogers,m during the Fall '08 term at BYU.

Page1 / 43

Chap 09 Proportioning - Designing and Proportioning Normal...

This preview shows document pages 1 - 14. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online