STRUCTURAL SYSTEMS (spd) Flashcards
properties of sections
1 area 2 centroid 3 statical moment 4 moment of inertia 5 section modulus 6 radius of gyration (ss)
The rate of changes of velocity, usually expressed a fraction of percentage of g, the acceleration of gravity.
acceleration(ss)
A substance, such as calcium chloride, added to a concrete mix to speed up its setting and strength development.
accelerator(ss)
A seismological instrument which is normally inoperative, but becomes activated when subject to strong earth motion, records the earth motion, and then shut off.
accelerograph(ss)
The pressure exerted by retained earth against retaining wall.
active pressure(ss)
A prepared substance added to concrete to alter or achieve certain characteristics.
admixture(ss)
Earthquake following the occurrence of a large earthquake, or main shock. The magnitude of an aftershock is usually less than that of the main shock.
Aftershock(ss)
The chemically inert element of concrete, usually consisting of sand, gravel, and/or other granular material.
aggregate(ss)
The incorporation of tiny air bubbles into concrete to improve its workability and resistance to frost.
air entrainment(ss)
A membrane enclosing a pressurized occupied space, which must be held down to its foundation.
air-supported structure(ss)
The maximum units of stress permissible in a structural member. It is called working stress
allowable stress(ss)
An increase in a building’s reponse to earthquake ground motion, resulting from the building’s period coinciding with that of the ground shaking, or other causes.
amplification(ss)
A device used to measure wind speed.
anemometer(ss)
The steepest angle with the horizontal at which a pile of loose earth will stand without sliding.
angle of repose(ss)
The most usual welding process used in building construction.In which intense heat is produce by an electric arc between the numbers to be joined and a metal wire or rod, called electrode
arc welding(ss)
A curve structure in which the internal stresses are essentially compression.
arch(ss)
The arbitrary limits which define the boundaries between the different states of rigidity or fluidity of fine-grained soils.
Atterberg limits (ss)
A longitudinal load which acts at the centroid of a member and perpendicular to its cross-section, thereby producing uniform tensile or compressive stress without any bending.
axial load (ss)
Reinforced concrete design in which there is simultaneous crushing of concrete and yielding of the reinforcing steel. To assure that yielding of the steel occurs before crushing of the concrete, the amount of reinforcing is limited to 75 percent of that which would produce a balanced design.
balanced design (ss)
The total design lateral force or shear at the base of a structure.
base shear (v) (ss)
The fastest mile wind speed which has a 2 percent probability of occurring in any one year measured at a point 33 feet (10 meters) above ground
basic wind speed (ss)
Reference points offset a given distance from the building line and set prior to excavation
batter boards (ss)
A structural member which supports loads perpendicular to its longitudinal axis.
beam (ss)
the load per unit area which can be safely support by the ground.
bearing capacity (ss)