0. Design and Control of Concrete Mixtures N EB001Fig. 2-17. High early strength cements are used where early concrete strength is needed, such as in (left to right) cold weatherconcreting, fast track paving to minimize traffic congestion, and rapid form removal for precast concrete. (65728, 59950, 68668)top). Type V cement, like other portland cements, is not White Portland Cementsresistant to acids and other highly corrosive substances. ASTM C 150 (AASHTO M 85) allows both a chemical White portland cement is a true portland cement thatapproach and a physical approach (ASTM C 452 expansion differs from gray cement chiefly in color. It is made totest) to assure the sulfate resistance of Type V cement. conform to the specifications of ASTM C 150, usually TypeEither the chemical or the physical approach can be speci- I or Type III; the manufacturing process is controlled so thatfied, but not both. the finished product will be white. White portland cement is made of selected raw materials containing negligible amounts of iron and magnesium oxides—the substancesAir-Entraining Portland Cements that give cement its gray color. White portland cement isSpecifications for three types of air-entraining portland used primarily for architectural purposes in structuralcement (Types IA, IIA, and IIIA) are given in ASTM C 150 walls, precast and glass fiber reinforced concrete (GFRC)and AASHTO M 85. They correspond in composition to facing panels, terrazzo surfaces, stucco, cement paint, tileASTM Types I, II, and III, respectively, except that small grout, and decorative concrete (Fig. 2-18). Its use is recom-quantities of air-entraining material are interground with mended wherever white or colored concrete, grout, orthe clinker during manufacture. These cements produce mortar is desired. White portland cement should be speci-concrete with improved resistance to freezing and thawing. fied as: white portland cement meeting the specifications ofSuch concrete contains minute, well-distributed, and com- ASTM C 150, Type [I, II, III, or V]. White cement is also usedpletely separated air bubbles. Air entrainment for most to manufacture white masonry cement meeting ASTM C 91concretes is achieved through the use of an air-entraining and white plastic cement meeting ASTM C 1328 (PCAadmixture, rather than through the use of air-entraining 1999). White cement was first manufactured in the Unitedcements. Air-entraining cements are available only in States in York, Pennsylvania in 1907. See Farny (2001) forcertain areas. more information.Fig. 2-18. White portland cement is used in white or light-colored architectural concrete, ranging from (left to right) terrazzo forfloors shown here with white cement and green granite aggregate (68923), to decorative and structural precast and cast-in-place elements (68981), to building exteriors. The far right photograph shows a white precast concrete building housing theASTM Headquarters in West Conshohocken, Pennsylvania. Photo courtesy of ASTM. 3011. Chapter 2 N Portland, Blended, and Other Hydraulic CementsBLENDED HYDRAULIC CEMENTS AASHTO M 240 also uses the above class designations for blended cement. The requirements of M 240 are almostBlended cements are used in all aspects of concrete identical to those in ASTM C 595.construction in the same manner as portland cements. ASTM C 1157 provides for six types of blended cementBlended cements can be used as the only cementitious as discussed under “Hydraulic Cements” below. Blendedmaterial in concrete or they can be used in combination cements meeting the requirements of C 1157 meet physicalwith other supplementary cementitious materials added at performance test requirements without prescriptive restric-the concrete plant. Blended cements are often designed to tions on ingredients or cement chemistry. This allows thebe used in combination with local pozzolans and slags. If a cement manufacturer to optimize strength and durabilityblended cement or portland cement is used alone or in properties through use of a variety of cementitious materi-combination with added pozzolans or slags, the concrete als, such as portland clinker, fly ash, slag, silica fume, andshould be tested for strength, durability, and other proper- calcined clay (Fig. 2-19).ties required in project specifications (PCA 1995 and A detailed review of ASTM C 595 and AASHTO M 240Detwiler, Bhatty, and Bhattacharja 1996). blended cements follows: Blended hydraulic cements are produced by inti-mately and uniformly intergrinding or blending two or Type ISmore types of fine materials. The primary materials areportland cement, ground granulated blast-furnace slag, fly Portland blast-furnace slag cement, Type IS, may be used inash, silica fume, calcined clay, other pozzolans, hydrated general concrete construction. Historical use of slag blendedlime, and preblended combinations of these materials (Fig. cements dates back to the beginning of the 20th century in2-19). Blended hydraulic cements must conform to the Europe, Japan, and North America (Abrams 1925). Inrequirements of ASTM C 595 (AASHTO M 240), Specifi- producing these cements, granulated blast-furnace slag iscation for Blended Hydraulic Cements, or ASTM C 1157, Per- either interground with portland cement clinker, separatelyformance Specification for Hydraulic Cement. ground and blended with portland cement, or produced ASTM C 595 recognizes five primary classes of with a combination of intergrinding and blending. Theblended cements as follows: blast-furnace slag content of this cement is between 25% Type IS Portland blast-furnace slag cement and 70% by mass. Subcategory types (optional special prop- Type IP and Type P Portland-pozzolan cement erties) such as air-entrainment, moderate sulfate resistance, Type I(PM) Pozzolan-modified portland cement or moderate heat of hydration may be specified by adding Type S Slag cement the suffixes A, MS, or MH. For example, an air-entraining Type I(SM) Slag-modified portland cement portland blast-furnace slag cement that has moderate sulfate resistance would be designated as Type IS-A(MS). Types IS, IP, P, I(PM), and I(SM) are general purpose See Klieger and Isberner (1967) and PCA (1995).cements (Fig. 2-12); these and subcategory types are re-viewed in the discussion below. Type IP and Type P Portland-pozzolan cements are designated as Type IP or Type P. Type IP may be used for general construction and Type P is used in construction not requiring high early strengths. These cements are manufactured by intergrind- ing portland cement clinker with a suitable pozzolan, by blending portland cement or portland blast-furnace slag cement and a pozzolan, or by a combination of intergrind- ing and blending. The pozzolan content of these cements is between 15% and 40% by mass. Laboratory tests indicate that performance of concrete made with Type IP cement as a group is similar to that of Type I cement concrete. Type IP may be designated as air-entraining, moderate sulfate resistant, or with moderate heat of hydration by adding theFig. 2-19. Blended cements (ASTM C 595, AASHTO M 240, and suffixes A, MS, or MH. Type P may be designated as lowASTM C 1157) use a combination of portland cement or clinker heat of hydration (LH), moderate sulfate resistant (MS), orand gypsum blended or interground with pozzolans, slag, or air entraining (A).fly ash. ASTM C 1157 allows the use and optimization of allthese materials, simultaneously if necessary, to make acement with optimal properties. Shown is blended cement Type I (PM)(center) surrounded by (right and clockwise) clinker, gypsum,portland cement, fly ash, slag, silica fume, and calcined clay. Pozzolan-modified portland cement, Type I(PM), is used in(68988) general concrete construction. The cement is manufactured 3112. Design and Control of Concrete Mixtures N EB001by combining portland cement or portland blast-furnace chemistry as found in other cement specifications. ASTM Cslag cement and a fine pozzolan. This may be accom- 1157 provides for six types of hydraulic cement as follows:plished by either (1) blending portland cement with a Type GU General usepozzolan, (2) blending portland blast-furnace slag cementwith a pozzolan, (3) intergrinding portland cement clinker Type HE High early strengthand a pozzolan, or (4) a combination of intergrinding and Type MS Moderate sulfate resistanceblending. The pozzolan content is less than 15% by mass of Type HS High sulfate resistancethe finished cement. Air-entrainment, moderate sulfate Type MH Moderate heat of hydrationresistance, or moderate heat of hydration may be desig- Type LH Low heat of hydrationnated in any combination by adding the suffixes A, MS, orMH. An example of an air-entraining, moderate-heat-of- In addition, these cements can also have an Option R—hydration Type I(PM) cement would be designated as Type Low Reactivity with Alkali-Reactive Aggregates—speci-I (PM)-A(MH). fied to help control alkali-silica reactivity. For example, Type GU-R would be a general use hydraulic cement withType S low reactivity with alkali-reactive aggregates. When specifying a C 1157 cement, the specifier usesSlag cement, Type S, is used with portland cement inmaking concrete or with lime in making mortar, but is not the nomenclature of “hydraulic cement,” “portlandused alone in structural concrete. Slag cement is manufac- cement,” “air-entraining portland cement,” “modifiedtured by either (1) blending ground granulated blast- portland cement” or “blended hydraulic cement” alongfurnace slag and portland cement, (2) blending ground with a type designation. For example, a specification maygranulated blast-furnace slag and hydrated lime, or (3) call for a Hydraulic Cement Type GU, a Blended Hydraulicblending a combination of ground granulated blast- Cement Type MS, or a Portland Cement Type HS. If a typefurnace slag, portland cement, and hydrated lime. The is not specified, then Type GU is assumed.minimum slag cont
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