AISC LRFD 1.pdf

GLOSSARYxxxiStrain-hardening strain. For structural steels that have a flat (plastic) region in thestress-strain relationship, the value of the strain at the onset of strain hardeningStrength design. A method of proportioning structural members using load factors andresistance factors such that no applicable limit state is exceeded (also called load andresistance factor design)Strength limit state. Limiting condition affecting the safety of the structure, in which theultimate load-carrying capacity is reachedStress. Force per unit areaStress concentration. Localized stress considerably higher than average (even in uniformlyloaded cross sections of uniform thickness) due to abrupt changes in geometryor localized loadingStrong axis. The major principal axis of a cross sectionStructural system. An assemblage of load-carrying components which are joined togetherto provide regular interaction or interdependenceStub column. A short compression-test specimen, long enough for use in measuring thestress-strain relationship for the complete cross section, but short enough to avoidbuckling as a column in the elastic and plastic rangesSubassemblage. A truncated portion of a structural frameSupported frame. A frame which depends upon adjacent braced or unbraced frames forresistance to lateral load or frame instability. (This transfer of load is frequently providedby the floor or roof system through diaphragm action or by horizontal cross bracingin the roof)Tangent modulus. At any given stress level, the slope of the stress-strain curve of a materialin the inelastic range as determined by the compression test of a small specimenunder controlled conditionsTemporary structure. A general term for anything that is built or constructed (usually tocarry construction loads) that will eventually be removed before or after completion ofconstruction and does not become part of the permanent structural systemTensile strength. The maximum tensile stress that a material is capable of sustainingTension field action. The behavior of a plate girder panel under shear force in which diagonaltensile stresses develop in the web and compressive forces develop in the transversestiffeners in a manner analogous to a Pratt trussToe of the fillet. Termination point of fillet weld or of rolled section filletTorque-tension relationship. Term applied to the wrench torque required to produce specifiedpre-tension in high-strength boltsTurn-of-nut method. Procedure whereby the specified pre-tension in high-strength boltsis controlled by rotation of the wrench a predetermined amount after the nut has beentightened to a snug fitUnbraced frame. A frame in which the resistance to lateral load is provided by the bendingresistance of frame members and their connectionsLRFD Specification for Structural Steel Buildings, December 27, 1999AMERICAN INSTITUTE OF STEEL CONSTRUCTION