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4 th  Article:  Effect of Mixing and Placing in Hot Weather on Hardened Concrete 4 th  Article:  Effect of Mixing and Placing in Hot Weather on Hardened Concrete

4 th Article: Effect of Mixing and Placing in Hot Weather on Hardened Concrete - PowerPoint Presentation

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4 th Article: Effect of Mixing and Placing in Hot Weather on Hardened Concrete - PPT Presentation

4 th Article Effect of Mixing and Placing in Hot Weather on Hardened Concrete Properties Department of Safety Engineering Korea Department of Civil and Environmental Engineering USA International Journal of Concrete Structures and ID: 761228

material concrete water noun concrete material noun water strength temperature surface verbto verb cement stress swing force volume state

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4 th Article: Effect of Mixing and Placing in Hot Weather on Hardened Concrete Properties Department of Safety Engineering, Korea Department of Civil and Environmental Engineering , USA International Journal of Concrete Structures and Materials http:// link.springer.com/article/10.1007%2Fs40069-013-0041-4

CEMENT & CONCRETE Cement (noun)A building material made by limestone and clay to a fine powder, which can be mixed with water and poured to set as a solid mass or used as an ingredient in making concrete. Ex.; Composition of cementConcrete (noun)A hard, strong construction material consisting of sand, conglomerate gravel, pebbles, broken stone, or slag in a mortar or cement matrix. Ex.; Concrete Structures

Casting To cast (verb) To shape (molten metal, cement etc.) by pouring into a mould; to make (an object) in such a way. It is a manufacturing process which a liquid material is usually poured into a mould and then allowed to solidify.

Curing To cure (verb)Curing is a process whereby a material is caused to form permanent molecular linkages by exposure to chemicals, heat, pressure, and/or weatheringEx.; Curing takes place immediately after concrete placing and finishing.Wetting (Watering)

HARDENED PROPERTIES OF THE CONCRETE Property (noun) ; An attribute or abstract quality associated with an individual, object or concept .Hardened (adj); sth which made hard; strengthened; reinforced; secured as to survive; made tough. Ex.; The hardened properties of the concrete are assessed by slump, air content, and compressive strength, while durability characteristics.

Resonance The increase in the amplitude of an oscillation of a system under the influence of a periodic force whose frequency is close to that of the system's natural frequency.Frequencies at which the response amplitude is a relative maximum are known as the system's resonant frequencies, or resonance frequencies.

Pushing a person in a swing with the natural interval of the swing (its resonant frequency) will make the swing go higher and higher (maximum amplitude). However attempts to push the swing at a faster or slower tempo will result in smaller arcs. This is because the energy the swing absorbs is maximised when the pushes are 'in phase' with the swing's natural oscillations, while some of the swing's energy is actually reduced by the opposing force of the pushes when they are not.A girl in the swing

Boil Test Is used to analyse bulk density, absorption, and voids of the field samples Bulk density: It is defined as the mass of many particles of the material divided by the total volume they occupy. The total volume includes particle volume, inter-particle void volume, and internal pore volume.Absorption: the passage of a gas, fluid (In scope) etc., through the material. Voids: An open space or a break in continuity; a gap (such as permeable pore space)

Slump NounA measure of the consistency of concrete in inches(Inch=2.54 cm)To slump (verb)To be in a noticeable deterioration in performance or quality.Ex.; the team went into a slump

CRACK ING PROBLEMSProblems based on cracking of the material (concrete)To Crack (verb)To break apart under pressure Ex.; In order to overcome cracking problems caused by the internal stress, a new design was proposed.

SUSP ICIOUS DETERIORATIONSDeterioration (noun)Process of changing to an inferior state a symptom of reduced quality or strength.Suspicious (adj )Indicating suspicion, mistrust, or fear Ex.; His suspicious behaviour brought him to the attention of the police. Ex.; It may be concluded that the suspicious deteriorations and cracks which are referable to hot weather would be due to other factors.

PERMEABLE AdjCapable of being permeated & penetrated, esp by liquids or gases.Ex.; permeable membranes; rock is permeable by water.(Opposite meaning- Impermeable)

SHR INKAGE To Shrink (verb)To become reduced in extent, compass, or value.Shrinkage (noun)The amount or proportion by which something shrinks.Ex.; Fabric shrinkage is a phenomena that occurs when fabric is exposed to heat and/or steam.

MATER IAL DURABILITYMaterial permanence by virtue of the power to resist stress or force.Ex.; Material durability is a major concern in structural design as it affects the particular material service life.UNIFORMITYnoun a state or condition in which everything isregular, homogeneous, or unvarying. Ex.; In order to obtain structures resistant to earthquakes, the aspect of uniformity must be considered.

ULT IMATE STRENGTHStrength (noun)The intensity of a force or power.Ex.; Strength of the materialUltimate (adj) The highest or most significant Ex.; The ultimate goal Ex.; Ultimate strength is defined as an absolute maximum compressive, shear, or tensile stress a material can bear without failure.

EVAPORATION To Evaporate (verb)To draw moisture from, as by heating, leaving only the dry solid portion.Evaporation (noun) The change of a liquid into a vapour at a temperature below the boiling point. Evaporation takes place at the surface of a liquid, where molecules with the highest kinetic energy are able to escape. When this happens, the average kinetic energy of the liquid is lowered, and its temperature decreases.

HUMIDITY Humid (adj)Containing or characterized by a high amount of water or water vapour.Ex.; humid air; a humid evening. Humidity (noun)the state of being humid; dampnessEx.; relative humidity, absolute humidity

MATUR ITYNounThe state or quality of being fully developed (mature).Ex.; Relationships between strength and maturity are common for many standard portland cement concrete pavement mixes.MatureAdjHaving reached a desired or final condition. Ex.; Mature CheeseALSO;   Worked out fully by the mind; considered:  a mature plan of action.

STRUCTURES The way in which parts are arranged or put together to form a whole; makeup.Ex.; Triangular structurePAVEMENTa hard-surfaced path for pedestrians alongside and a little higher than a road PAVEMENT DAMAGE Damage (noun); Harm or injury to property or a person, resulting in loss of value or the impairment of usefulness.Ex.; Pavement damage impacts public safety and creates hazards.

PAVEMENT DAMAGE

SURFACE SCAL INGSurface (noun)the outer boundary of a material layer constituting or resembling a boundary.Ex.; There is a special cleaner for these surfaces.Ex.; The cloth had a pattern of red dots on a white surface.Surface ScalingA flaky film formed on a surface of concrete.Ex.; The repetitive cycles of freezing will cause the concrete surface to scale.

SURFACE SCALING

CONCRETE SLABSSlab (noun)A large, flat shaped piece of material such as stone, concrete, clay, butter etc.

L IMESTONE NounA common sedimentary rock consisting mostlyof calcium carbonate, CaCO3, used as a building stone and in the manufacture of lime and cement.GRAVELNoun Small fragments of rock, used for laying on the beds of roads and railroads.Ex.; Gravels constitute the majority of coarse aggregate used in concrete with crushed stone making up most of the remainder. Limestone pavement

G RAVELFine gravel Coarse gravel

AGGREGATE NounAny of various loose, particulate materials, as sand or gravel added to a cementing agent to make concrete etc.

THRESHOLD TEMPERATUREThreshold; The point that must be exceeded to begin producing a given effect or result. ORThe quantitative point at which an action is triggered, especially a lower limit.Ex.; An important precaution is to ensure that the plastic concrete temperature be kept suitably below threshold temperature.AMB IENT AIR TEMPERATURE Ambient ( adj ); of or relating to the immediate surroundings. Ex.;  the ambient temperature was 15°C. Ex.; The ambient temperature is a phrase which is used to describe the outside temperature.

STOCKP ILESNounA pile (mass) accumulated for future use.coarse aggregate stockpiles

AG ITATING TRUCKSTRANSMIXERlarge truck with a rotating canister used to storeand mix cement.Ex.; It is convenient to transport the concrete in agitating trucks (transmixers). AVERAGE HAUL T I ME Amount of time to carry (to transport) something (cement). Ex.; In transposting concrete the average haul time was reported as 25–30 min.

D ISTRESSNounA force or a system of forces producing deformation or strain acting per unit area.Ex.; Low temperature related distress predicted and observed in experiments of concrete.

EXPER IMENTAL TESTExperiment (noun)A test under controlled conditions made to either demonstrate; a known truth, examine the validity of a hypothesis, or determine the efficiency of something previously untried Experimental (adj ) relating to or based on experiment; Ex.; "experimental physics” Experiment and Test could be used in conjunction. “Experiment”, itself refers to “Test”

COMPRESS IVE STRENGTHThe resistance of a material to breaking under compression.The capacity of a material or structure to withstand loads tending to reduce size. It can be measured by plotting applied force against deformation in a testing machine. Some material fracture at their compressive strength limit; others deform irreversibly, so a given amount of deformation may be considered as the limit for compressive load. Compressive strength is a key value for design of structures.

COMPRESS IVE STRENGTH

FLEXURAL STRENGTH Also known as bend strength, or fracture strength.A mechanical parameter for brittle material, is defined as a material's ability to resist deformation under load.  The flexural strength represents the highest stress experienced within the material at its moment of rupture. It is measured in terms of stress.

ELASTICITY When an elastic material is deformed due to an external force, it experiences internal forces that oppose the deformation and restore it to its original state if the external force is no longer applied. There are various elastic module, such as Young's modulus, the shear modulus, all of which are measures of the inherent stiffness of a material as a resistance to deformation under an applied load. In physics, elasticity is a physical property of materials which return to their original shape after they are deformed.Ex.; The elasticity of concrete is relatively constant at low stress levels but starts decreasing at higher stress levels.

S ATURATED SURFACE DRY MASSIn order to determine the saturated surface-dry mass in cold-water saturation technique, the samples were simply immersed in cool water at approximately 21 °C for more than 48 hours.Saturated (adj): filled with water (soaked) to capacity; having absorbed all that can be taken up. Mass (noun): Some quantity of any material (for liquids or solids[in scope])  Ex.; Solid tumours refer to a  solid mass  of cancer cells that grow in organs.

TO VIBRATE VerbTo move back and forth rapidly, oscillate; Ex.; It causes the table to vibrate when mobile phone vibrates.TO IMMERSEVerbTo put under the surface of a liquid.Ex.; Archimedes determined the volume of objects by immersing them in water.Immersion (noun): the total submerging of sth in water.

TO ALTER VerbTo change the form or structure of sth Ex.; A barrage could supply much of south Wales and the West Country, but would dramatically alter the local environment. TO ESTABLISHVerbTo prove and cause to be accepted as true; to establish a fact; to demonstrate. Ex.; More research is required to establish a database and information on the behaviour of structures under these conditions.To appoint or constitute for permanence. Ex.; T his result cannot be established at the 95 % confidence level.

TO SOAKVerbTo immerse in liquid to the point of saturation or thorough permeation .Ex.; Soak the beans overnight before cooking.Ex.; Test samples were left to soak in water for 1 week, changing the water daily.TO VARY FROM ... TO .. (TO DIFFER FROM .. TO)Verb To change with time.Ex.; Gravel concentration  varied from 2 to  85 percent and generally decreased with depth throughout the drill.

TO SUSPENDVerbTo be held in suspension (The state of a solid when its particles are mixed with, but not dissolved in a fluid, and are capable of separation by straining)Ex.; The mass which suspended in water is used in some experimental tests of materials. TO SPRINKLE Verb To drip in fine dropsEx.; Sprinkling water on fresh concrete is a common way of curing uncolored concrete.

TO CONDUCT (TO CARRY OUT) VerbTo direct the course of; manage or control.Ex.; The researchers conduct these tests under well-controlled laboratory condition, so they cannot reflect the actual field condition with many variables.TO CAUSEVerbTo reason for; To result in.Ex.; As silica gel swells when it absorbs moisture, the material can cause concrete to crack.

TO INVESTIGATE VerbTo observe or inquire into in detail; examine systematically.Ex.; How can we investigate roadway sites with suspected hot weather concrete problems were investigated.TO POURVerbTo stream or flow continuously  Ex.; This local road was poured in two stages; such as eastbound side and westbound side.

TO EXAMINE VerbTo observe carefully or critically; to inspect; to study or analyseEx.; She examined the room for clues.Ex.; He examined a tissue sample under a microscopeEx.; This article will examine several projects that successfully used decorative concrete to produce highly sustainable results.TO REQUIREVerbto impose as a necessity; make necessaryEx.; This work requires precision.

TO EXPOSE VerbTo subject to an action, influence, or condition.Ex.; If the material is exposed to high temperature, it cannot work properlyTO SWELL (additional verb)VerbTo increase in size or volume as a result of internal pressure; expand.Ex.; When concrete gains moisture, it slightly expands or swells . 

TO EVALUATE VerbTo examine and judge carefully; appraise. Ex.; You should be the first one to evaluate your own work before you show it.TO EXHIBITVerbTo show outwardly; to display.Ex.; Two materials exhibit the same behaviour under the similar stress levels.

TO INCREASE VerbTo become greater or larger, to go upAn increase (noun) ;Ex.; There has been an increase in the number of delegates attending the committeeTO DECREASE VerbTo reduce to became smaller; to decline; to go downA decrease (noun); Ex.; A sharp decrease in weather temperature has resulted in many people with flu.