Cement and Concrete History History Composition Composition Testing Testing Key Terms Key Terms

Key Terms Designation C Air-entraining hydraulic cement – hydraulic cement containing an air entraining addition in such amount as to cause the product to entrain air in mortar within specified limits. Air-entraining hydraulic cement – hydraulic cement containing an air entraining addition in such amount as to cause the product to entrain air in mortar within specified limits. Blast furnace slag – nonmetallic product consisting essentially of silicates and aluminosilicates of calcium and other bases that is developed in a molten condition simultaneously with iron in a blast furnace. Blast furnace slag – nonmetallic product consisting essentially of silicates and aluminosilicates of calcium and other bases that is developed in a molten condition simultaneously with iron in a blast furnace. Hydration – chemical reaction between hydraulic cement and water forming new compounds most of which have strength- producing properties. Hydration – chemical reaction between hydraulic cement and water forming new compounds most of which have strength- producing properties. Hydraulic cement – a cement that sets and hardens by chemical interaction with water and is capable of doing so under water. Hydraulic cement – a cement that sets and hardens by chemical interaction with water and is capable of doing so under water. Portland cement – a hydraulic cement produced by pulverizing portland-cement clinker and usually containing calcium sulfate. Portland cement – a hydraulic cement produced by pulverizing portland-cement clinker and usually containing calcium sulfate.

ASTM Portland Cement Types Type Characteristics and Use TYPE I, IA, STANDARD General Purpose, Most residential applications TYPE II, IIA, MODIFIED Reduced heat of hydration, increased sulfate resistance TYPE III, IIIA HIGH EARLY STRENGTH High strengths in one to three days TYPE IV, LOW HEAT Heat during hydration kept to a minimum; intended for large masses, e.g., dams TYPE V, SULFATE RESISTANT Especially good for marine structures and soils with high alkali

Cement A finely pulverized material consisting principally of compounds of lime, silica, alumina, and iron.

Concrete A monolithic, ceramic product of aggregates bonded with cement, such as Portland or asphalt. A monolithic, ceramic product of aggregates bonded with cement, such as Portland or asphalt.

Composition of Concrete Air-entrained Non-air-entrained Air-entrained Non-air-entrained Cement15%15% Water 18%21% Air 8% 3% Fine Aggregate 28%30% Course Aggregate 31%31% Note: All values are approximate

Fine and Course Aggregates Fine aggregates – stone or sand that can pass through a sieve with ¼” square holes. Fine aggregates – stone or sand that can pass through a sieve with ¼” square holes. Course Aggregate – rock or stone greater than ¼”. Usually not larger than 1 ½” Course Aggregate – rock or stone greater than ¼”. Usually not larger than 1 ½”

History Roman Empire – Colosseum and other structures made with a type of cement made from slaked lime and pozzolona (volcanic ash from Mt. Vesuvius) First Hydraulic Cement. Roman Empire – Colosseum and other structures made with a type of cement made from slaked lime and pozzolona (volcanic ash from Mt. Vesuvius) First Hydraulic Cement John Smeaton – discovers that cement made from limestone with a substantial volume of clay hardens under water John Smeaton – discovers that cement made from limestone with a substantial volume of clay hardens under water Joseph Aspdin – invents Portland Cement 1824 Joseph Aspdin – invents Portland Cement

Hydration The chemical reaction between hydraulic cement and water forming new compounds most of which have strength –producing properties. The chemical reaction between hydraulic cement and water forming new compounds most of which have strength –producing properties.

Composition of Concrete 11% Cement (usually Portland) 11% Cement (usually Portland) 16% Water 16% Water 6% Air 6% Air 26% Sand 26% Sand 41% Gravel or Crushed Stone 41% Gravel or Crushed Stone

Fiber Reinforced Concrete Low Fiber volume composite: concrete contains less than 1% fiber. It is used for field applications involving large volumes of concrete. The fibers do not significantly increase the strength of the concrete. Low fiber volume concrete is used for paving roads. Low Fiber volume composite: concrete contains less than 1% fiber. It is used for field applications involving large volumes of concrete. The fibers do not significantly increase the strength of the concrete. Low fiber volume concrete is used for paving roads. High Fiber Volume Concrete: Typically used for thin sheets with cement mortar mix. The fiber volume in this mix ranges from 5% to 15%. High Fiber Volume Concrete: Typically used for thin sheets with cement mortar mix. The fiber volume in this mix ranges from 5% to 15%.

Fiber Reinforced Concrete High Fiber Volume Composite : The fiber volume in this mix can be as high as 40%. This significantly increases the strength and toughness of the mix. The reinforcement in High Fiber Volume Composite concrete is usually in sheet form. This reinforced concrete type is used in roof and wall panels. High Fiber Volume Composite : The fiber volume in this mix can be as high as 40%. This significantly increases the strength and toughness of the mix. The reinforcement in High Fiber Volume Composite concrete is usually in sheet form. This reinforced concrete type is used in roof and wall panels.

Standardized Tests of Concrete ASTM C-143 Slump Test ASTM C-143 Slump Test ASTM C-39 Compressive Strength Test ASTM C-39 Compressive Strength Test ASTM C-78Flexural Strength Test ASTM C-78Flexural Strength Test

ASTM C-39 Standard Test Method Compressive Strength of Cylindrical Concrete Specimens Procedure 7.3 All test specimens for a given test age shall be broken within the permissable time tolerances prescribed as follows: Test AgePermissible Tolerance 24 hours+/-.5 h or 2.1% 3 days2 h or 2.8% 7 days6 h or 3.6% 28 days20h or 3.0% 90 days2 days or 2.2%

ASTM C-39 Standard Test Method Compressive Strength of Cylindrical Concrete Specimens Procedure 8.1 If the specimen length to diameter ratio is less than 1.8, correct the result obtained in 8.1 by multiplying by the appropriate correction factor in the following table: L/D Factor:

Test Cylinders

TABLE 11.2 CONCRETE MIXES FOR SELECTED APPLICATIONS APPLICATION CEMENT CONTENT BAGS/YD MAX SIZE AGGREGATE WATER/ CEMENT RATIO GALS/SACK 28 TH DAY COMPRESSIVE STRENGTH 8" Basement Wall /2 " " Basement Wall 6.21"63500 Stairs6.21"63500 Driveways, Porches 6.21"63500

Table 11.3 ASTM Time Tolerances For Concrete Compressive Strength Test TEST AGEPERMISSABLE TOLERANCE 24 Hours±0.5 h OR 2.1% 3 Days2 h OR 2.8% 7 Days6 h OR 3.6% 28 Days20 h OR 3.0% 90 Days2 days OR 2.2%