Cement and Aggregates

8/3/2019 Cement and Aggregates

1/20

CEMENT AND AGGREGATESbuilding technology: materials in building construction

QUE,CHESTER P.

LACSON, RONEL B.2010-10401

2010-10591

reported by:

PAMANTASAN NG LUNGSOD NG MAYNILAcollege of architecture and urban planning


2/20

CEMENTa calcined mixture of clay and

limestone, finely pulverized andused as an ingredient inconcrete and mortar. The term is

frequently used incorrectly forconcrete.

Hydraulic CementA bonding agent that reacts with water to form a hard stone-likesubstance that is resistant to disintegration in water.

Portland CementWidely used in various small and large constructions includingroads and highways. Portland cement is not a brand but a type ofhydraulic cement.


3/20

Portland Cement is categorized into five types:Type I Normala portland cement used for general construction, having none of thedistinguishing qualities of the other types.

Type II Moderatea portland cement having a reduced content of tricalcium aluminate,making it more resistant to sulfates and causing it to generate less heatof hydration.

Type III High-Early Strengtha very finely ground portland cement having an increased content oftricalcium silicate, causing it to cure faster and gain strength earlier thannormal portland cement.

Type IV Low Heata portland cement having a reduced content of tricalcium silicate andan increased content of dicalcium silicate, causing it to generate lessheat of hydration than normal portland cement.

Type V Sulfate Resistinga portland cement having a reduced content of tricalcium aluminate,

lessening the need for gypsum, a sulfate normally added to cement toretard its setting time


4/20

Natural Cement

A naturally occurring clayey limestone which when calcined andfinely pulverized produces a hydraulic cement.

Pozzolana siliceous material, as fly ash, that reacts chemically with slaked

lime in the presence of moisture to form a slow-hardening cement,named after a natural cement from Pozzuoli, an ancient Romantown near Vesuvius. Also pozzolona, pozzuolana.

Siliceouscontaining silica or a silicate.

Fly Ashfine particles of ash recovered from the waste gases of a solid-fuelfurnace.


5/20

TricalciumSilicatea compound constituting about half the volume of

portland cement and responsible for the hardening orearly gain in strength of the cement.

DicalcuimSilicatea compound constituting about one-quarter of thevolume of Portland cement and responsible for the agingor long-term gain in strength of the cement.

TricalciumAluminatea compound constituting about one-tenth of the volumeof Portland cement and responsible for the initial setting ofthe cement.


6/20

Air-entraining Portland Cement

a TypeI, Type II, or Type III portland cement to which asmall quantity of an air-entraining agent has beeninterground during manufacture: designated by thesuffix A, as Type IA, Type IIA, or Type IIIA.

White Portland Cementa portland cement produced from raw materials low iniron oxide and manganese oxide, the substances thatgive concrete its gray color: used in precast concretework and in the making of terrazzo, stucco, and tilegrout.


7/20

Sulfate Actionan expansive reaction occurring when the cementmatrix of concrete or mortar comes in contact withsulfates dissolved in ground water or in soil.

Entrained AirMicroscopic, spherical air bubbles, typically 0.004 to 0.04in. (0.1 to 1.0 mm) in diameter intentionally dispersed in aconcrete or mortar mix by an air-entraining agent.

Cement Pastea mixture of cement and water for coating, setting, andbinding the aggregate particles together in a concreteor mortar mix.


8/20

Mortara plastic mixture of lime or cement, or a combination of both, withsand and water, used as a bonding agent in masonry

construction.Cement Mortara mortar made by mixing portland cement, sand,, and water.

Cement Lime-Mortara cement mortar to which lime is added to increase its plasticityand water-retentivity.

Masonry Cementa proprietary mix of portland cement and other ingredients, as

hydrate lime, plasticizers, air-entraining agents, and gypsum, requiringonly the addition of sand and water to make cement mortar.

Cement Temperthe addition of portland cement to lime plaster to improve its strength

and durability.


9/20

AGGREGATES


10/20

AGGREGATES

any various hard, inert, mineral materials, as sand

and gravel, added to a cement paste to make

concrete or mortar. Since aggregate representsfrom 60% to 80% of the concrete volume, its

properties are important to the strength, weight,

and fire-resistance of the hardened concrete.

Aggregate should be hard, dimensionally stable,

and free of clay, silt, and organic matter which

can prevent the cementing matrix from binding

the particles together.


11/20

AGGREGATES

BUILDING TECH 1: MATERIALS IN BUILDING CONSTRUCTION


12/20

Fine Aggregateaggregate consisting of sand having a particle size smaller than

in. (6.4 mm): specif. the portion of aggregate that will pass through3/8 in. (9.5 mm) sieve, almost entirely through a No.4 (4.8 mm)sieve, and be predominantly retained on a No. 200 (74) sieve.

Coarse Aggregateaggregate consisting of crushed stone, gravel, or blast-furnaceslag having a particle size larger than in. (6.4 mm): specif. theportion of the aggregate that is retained on a No.4 (4.8mm) sieve.The maximum size of coarse aggregate in reinforced concrete islimited by the size of the section and the spacing of the reinforcingbars.

Graded Aggregateaggregate having a particle-size distribution characterized byuniform grading. Graded aggregate requires the least amount of

cement paste to fill the voids and surround the particles.


13/20

Graded Aggregate

Particle-size distributionthe range of particle sizes in a granular material, expressed eitheras the cumulative percentage by weight of particles smaller orlarger than a specified sieve opening, or as the percentage by

weight of the particles that range between specified sieveopenings.

Uniform Gradinga particle-size distribution in which aggregate particles varyuniformly from fine to coarse without a preponderance of anyone size or group of sizes.


14/20

TYPES OF AGGREGATES

AGGREGATES COARSE AGGREGATES

BUILDING TECH 1: MATERIALS IN BUILDING CONSTRUCTION

GRADED AGGREGATES FINE AGGREGATES


15/20

Coarse Aggregates is that portion of anaggregates that is retained on number

4 (4.76mm) size which usually come from:

1. Natural gravel deposits which areformed by water, wind or glacialaction.

2. Manufactured by crushing rock,stone, boulder and large cobble stone.


16/20

Four Kinds of CommonCoarse Aggregate

1. Limestone or calcium bearing materials.

2. Basalts, granite and related igneous rock.

3. Sandstone and quartzite.

4. Rock, such as opal and chert composedmainly of amorphous silicon dioxide.


17/20

Four Kinds of Common Coarse AggregateBUILDING TECH 1: MATERIALS IN BUILDING CONSTRUCTION

LIMESTONE OPAL

CHERTQUARTZITESANDSTONE

GRANITE


18/20

Conditions for maximumsize of coarse aggregates:

1. It shall easily fit into the forms and inbetween reinforcing bars.

2. It should not be larger than 1/5 of thenarrowest dimension of the forms of

1/3 of the depth of the slab nor ofthe minimum distance between thereinforcing bars.


19/20

Expanded Shalea strong lightweight aggregate obtained by the exfoliation ofclay or shale. Also called expanded clay.

Exfoliationthe splitting or swelling of certain minerals into a scaly aggregatewhen heated.

Perlitea volcanic glass expanded by heat to form lightweight, sphericalparticles, used as nonstructural lightweight aggregate and asloose-fill thermal insulation. Also, pearlite.

Vermiculitemica expanded by heat into very light, wormlike threads, used asnonstructural lightweight aggregate and as loose-fill thermalinsulation.


20/20

END OF PRESENTATIONBUILDING TECH 1: MATERIALS IN BUILDING CONSTRUCTION

Documents

Cement and Aggregates