Tapered Members
A built up plate member consisting of flanges welded to a variable depth web.
Tapered Tread Wheels
End truck wheels with treads that are tapered, the large diameter being toward the
center of the span.
Temperature Reinforcing
Light weight deformed steel rods or wire mesh placed in concrete to resist possible
cracks from thermal expansion or contraction.
Tensile Strength
The longitudinal pulling stress a material can bear without tearing apart.
Tension Forces
Forces acting on a member tending to elongate it.
Thermal Block
A thermal insulating material that is placed between the metal building roof and the
compressed insulation over the purlins. Also known as a “thermal spacer block”.
Thermal Conductance, (C-factor)
The time rate of heat flow through unit area of a body induced by unit temperature
difference between the body surfaces. Units are Btu / (hour × ft2 × °F) [Imperial
system] or Watts / (m2 × °C) [SI system]. See "Thermal resistance".
Thermal Conductivity, (k-factor)
The time rate of heat flow through unit thickness of a flat slab of a homogenous
material in the perpendicular direction to the slab surfaces induced by unit temperature
gradient. Units for k are (Btu × in) / (hour × ft2 × °F) or Btu / (hour × ft × °F) [Imperial
system] and Watts / (m × °C) [SI system]. See "Thermal resistivity".
Thermal Emittance
The ratio of the radiant heat flux emitted by a sample to that emitted by a blackbody
radiator at the same temperature. (Total Thermal Emittance). Values are expressed
from 0 to 1.0, with 1.0 being the maximum emittance possible.
Thermal Movement
The expansion and contraction that occurs in materials due to temperature change.
Through-Fastened Roof System
A through-fastened roof system is one in which the roof panels are attached directly to
the roof substructure with fasteners which penetrate through the roof sheets and into
the substructure.
Through Ties
Reinforcing steel, usually in the concrete, extending from one column pier to the other
column pier, tying the two columns of a rigid frame together to resist thrust.
Thrust
The horizontal component of a reaction usually at the column base.
Tie
A structural member that is loaded in tension.
Ton
2000 pounds.
Torque Wrench
A wrench containing an adjustable mechanism for measuring and controlling the
amount of torque or turning force to be exerted – often used in tightening nuts and
bolts.
Track
A metal way for wheeled components; specifically, one or more lines of ways, with
fastenings, ties, etc., for a craneway, monorail or slide door.
Translucent Light Panels
Panels used to admit light.
Transverse
The direction parallel to the main frames.
Trapezoidal Panel
A panel configuration whose edge profile forms an open geometric form, roughly in
the shape of a trapezoid.
Tributary Area
The area directly supported by the structural member between contiguous supports.
Trim
The light gage metal used in the finish of a building, especially around openings and at
intersections of surfaces. Often referred to as flashing. When contrasted, "trim" is
generally more decorative, while "flashing" serves more as functional weatherproofing.
Trolley (Crane)
The unit carrying the hoisting mechanism.
Trolley Frame (Crane)
The basic structure of the trolley on which are mounted the hoisting and traversing
mechanisms.
Truss
A structure made up of three or more members, with each member designed to carry a
tension or compression force. The entire structure in turn acts as a beam.
Turnout
See "Kick-Out".
Turn-of-the-Nut Method
A method for pre-tensioning high strength bolts. The nut is turned from the "Snug
tight" position, corresponding to a few blows of an impact wrench or the full effort of a
man using an ordinary spud wrench, the amount of rotation required being a function
of the bolt diameter and length.
Twist Off Bolts
Bolts with a segment which shears off at a predetermined torque during bolt tightening.
These bolts utilize a specially designed wrench for proper installation.