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 Temper
The addition of water to the cement mix whether at the batch plant,
during transit or at the jobsite to achieve the specified water to
cement ratio.
Temperature Reinforcement
Reinforcement used to carry temperature stresses.
Temperature Rise The increase of concrete temperature caused by
heat of hydration and heat from other sources.
Tilt-up A method of concrete construction such as where members are
cast horizontally near their eventual position, usually on a recently
placed slab, and then tilted into place after removal of forms.
Transit-Mixed Concrete Concrete produced from a central-batching
plant, where the materials are proportioned and placed in truck-mixers
for mixing enroute to the job or after arrival there.
Tremie A pipe through which concrete may be placed under water,
having at its upper end a hopper for filling, and a bale which permits
handling of the assembly by a derrick.
Truck Mixer A concrete mixer capable of mixing concrete in transit
when mounted on a truck chassis.
Ultimate Strength The maximum resistance to loads that a structure
or member is capable of developing before failure occurs, or, with
reference to cross sections of members, the largest axial force, shear
or moment a structural concrete cross section will support.
Unit Water Content The
quantity of water per unit volume of freshly mixed concrete, often
expressed as gallons or pounds per cubic yard. This is the quantity of
water on which the water cement ratio is based, and does not include
water absorbed by the aggregate
Vapor Pressure The pressure exerted by a vapor that is calculated
based upon relative humidity and temperature. The higher the humidity
and higher temperature, in degrees Fahrenheit, the greater the vapor
pressure exerted.
Vapor When a liquid changes to a gaseous form. The ability of the
gas to hold moisture will reduce as temperatures reduce; more moisture
can be contained in the gas as the temperatures increase.
Vaporproof A material that is totally immune to the passage of a gas
under pressure. Any material that is truly vaporproof will inherently be
waterproof.
Vibration Energetic
agitation of concrete to assist in its consolidation, produced by
mechanical oscillating devices at moderately high frequencies.
A. External
vibration employs a device attached to the forms and is particularly
applicable to the manufacture of precast items and for the vibration of
tunnel lining forms.
B. Internal
vibration employs an element which can be inserted into the concrete;
and is more generally used for cast-in-place construction.
Vicat Apparatus A penetration device used to determine the setting
characteristics of hydraulic cements.
Wagner Fineness The fineness of materials such as portland cement
expressed as total surface area in centimeters per gram as determined by
the Wagner turbidimeter apparatus and procedure.
Water-Cement Ratio The ratio of the amount of water, exclusive of
that absorbed by the aggregates, to the amount of cement in a concrete
mix. Typically expressed as percentage of water, by weight in pounds,
to the total weight of portland cement, fly ash, and any other
cementitious material, per cubic yard, exclusive of any aggregates.
Waterproof A material or surface that is impervious or unaffected by
water in its liquid form.will repel water in it's liquid form but may
not necessarily be vaporproof.
Water Vapor Pressure The pressure exerted by water vapor. Air that
contains higher amounts of water vapor exerts a higher vapor pressure
than air which has a lower amount of has a higher water vapor pressure
In concrete water vapor pressure is calculated by the difference between
the vapor pressure of the concrete and the ambient relative humidity and
temperature and in contact with the soil. that is calculated by; based
upon relative humidity and temperature. The greater the difference
between the water vapor and ambient humidity and temperature, in degrees
Fahrenheit. the greater the water vapor pressure exerted.
Wetting Agent A substance capable of lowering the surface tension of
liquids, facilitating the wetting of solid surfaces and permitting the
penetration of liquids into the capillaries.
Workability The ease with which a given set of materials can be
mixed into concrete and subsequently handled, transported, placed and
finished with a minimum loss of homogeneity.
Yield The amount of concrete produced by a given combination of
materials, the total weight of ingredients divided by the unit weight of
the freshly mixed concrete; also, The cubic test of concrete produced
per sack of cement; also, the number of product units, such as block,
produced per batch of concrete or sack of cement. |
