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Revised June 2015
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either moderate absorption or moderate covering of moisture; implies less moisture than a wet condition and slightly more moisture than a moist condition.
treatment of concrete or mortar to retard the passage or absorption of water, or water vapor, either by application of a suitable coating to exposed surfaces, or by use of a suitable admixture or treated cement, or by use of a pre-formed film such as polyethylene sheets placed on grade before placing a slab. (See also vapor barrier.)
(See ACI 562 for code specific language.)
a hand-manipulated straightedge, usually 3 to 8 ft (1 to 2.5 m) long, used in the early-stage leveling operations of concrete or plaster, preceding supplemental floating and finishing.
a list of significant properties, methods for determining those properties, and a format for reporting that information.
a constant load that in structures is due to the mass of the members, the supported structure, and permanent attachments or accessories.
a separation of bonded surfaces.
movement of a point on a structure or structural element, usually measured as a linear displacement transverse to a reference line or axis.
a change in shape or size.
deformation caused by time-dependent factors such as autogenous volume change, thermal contraction or expansion, creep, shrinkage, and swelling.
a detrimental change in the physical and/or chemical properties of a material.
a separation along a plane parallel to a surface as in the separation of a coating from a substrate or the layers of a coating from each other, or in the case of a concrete slab, a horizontal splitting, cracking, or separation of a slab in a plane roughly parallel to, and generally near, the upper surface; often caused by corrosion of embedded reinforcing steel.
equipment which introduces shotcrete material into the delivery hose.
hose used to place shotcrete, grout, or pumped concrete or mortar; also known as a
conveying hose or material hose.
ratio of required strength to design strength.
breakdown of the protective oxide film on a metal surface.
(See ACI 562 for code specific language.)
code, standards, loads, displacement limits, materials, connections, details, and protections used in the design of mandated and voluntary work.
process for controlled release of forces in an unbonded post-tensioned tendon.
physical manifestation of failure of a material (e.g., cracking, delamination, flaking, pitting, scaling, spalling, staining) caused by service conditions or internal autogenous influences. (See also disintegration and weathering.)
the temperature of a surface at a given ambient temperature and relative humidity, at which condensation of moisture will occur.
the removal and control of subsurface groundwater from soil or rock formations. (See also unwatering.)
an inclined or slanted crack that is nonparallel to the transverse or longitudinal axis of a member.
a method for removal of concrete sections with a wire that contains modules impregnated with diamonds; the wire is wrapped around the concrete mass to be cut and connected to a power pack so that it travels in a continuous loop.
a relative variation in rate and/or magnitude of settlement in different areas of a structure.
the movement of molecules from an area where their concentration is high to an area where their concentration is low.
a shear test in which a material under an applied normal load is stressed to failure by moving one section of the specimen relative to the other section in direction perpendicular to the applied normal load.
fading or other alteration of a color that changes the normal appearance.
two-component devices that contain parallel or concentric dispensing cartridges; plungers for each cartridge are depressed simultaneously to extrude the adhesive components in the proper proportions, usually through a static mixing tube.
a material capable of increasing the fluidity of cement paste, mortars, or concrete by reduction of interparticle attraction.
physical manifestation of cracking and distortion in a structure as the result of stress, chemical action, or both.
1) a steel pin, commonly a plain round steel bar, which extends into adjoining portions of a concrete construction, as at a joint in a pavement slab, so as to transfer shear loads; 2) a deformed reinforcing bar intended to transmit tension, compression, or shear through a construction joint.
a pipe or channel used to remove water.
a row of open holes drilled parallel to and downstream from the grout curtain of a dam for the purpose of reducing uplift pressures.
an opening or passageway within a concrete structure from which grout holes or drainage holes are drilled. (See also grout gallery.)
use of a mechanically powered rotating shaft and mixing paddle to combine the components of concrete repair materials, usually in a bucket or other separate vessel.
pipe nipple for grout hose connection which is embedded in a short entry hole drilled into the concrete surface.
very dry portland-cement mortar or polymer-cement mortar usually compacted by ramming.
hand placement of very dry mortar and the subsequent tamping or ramming of the mortar into a confined place.
a dry mixture of hydraulic cement and fine aggregate (either natural or special metallic) that is distributed evenly over the surface of concrete flatwork and worked into the surface before time of final setting and then floated and troweled to desired finish; the mixture either may or may not contain pigment.
formed or cored openings in a concrete member to accommodate a tendon for post- tensioning.
ability of a material or structure to resist weathering action, chemical attack, abrasion, and other conditions of service and maintain serviceability over a specified time.
a measurement of the ability of a material to retain its properties over a period of time in which it is exposed to deleterious conditions; usually expressed as percentage of the value of a given property before exposure.
the development of a powdered material at the surface of a cementitious material.
an additive whose primary purpose is to change the color of grout or water.
dynamic modulus of elasticity
the modulus of elasticity computed from the size, weight, shape, and fundamental frequency of vibration of a concrete test specimen, or from pulse velocity.
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