AISC LRFD 1.pdf

6 MATERIAL [Sect. A3.Specification for Low-Alloy Steel Electrodes for Flux Cored Arc Welding, AWSA5.29Specification for Welding Shielding Gases, AWS A5.32/A5.32MManufacturer’s certification shall constitute sufficient evidence of conformity withthe standards. Filler metals and fluxes that are suitable for the intended applicationshall be selected.6. Stud Shear ConnectorsSteel stud shear connectors shall conform to the requirements of Structural WeldingCode—Steel, AWS D1.1.Manufacturer’s certification shall constitute sufficient evidence of conformity withthe code.A4. LOADS AND LOAD COMBINATIONSThe nominal loads and factored load combinations shall be as stipulated by theapplicable code under which the structure is designed or dictated by the conditionsinvolved. In the absence of a code, the loads and factored load combinations,including impact and crane loads, shall be those stipulated in ASCE 7. For designpurposes, the loads stipulated by the applicable code or ASCE 7 shall be taken asnominal loads.A5. DESIGN BASIS1. Required Strength at Factored LoadsThe required strength of structural members and connections shall be determinedby structural analysis for the appropriate factored load combinations as stipulatedin Section A4.Design by either elastic or plastic analysis is permitted, except that design by plasticanalysis is permitted only for steels with specified minimum yield stresses notexceeding 65 ksi (450 MPa) and is subject to provisions of Sections B5.2, C1.1,C2.1a, C2.2a, E1.2, F1.3, H1, and I1.Beams and girders composed of compact sections, as defined in Section B5.1, andsatisfying the unbraced length requirements of Section F1.3 (including compositemembers) which are continuous over supports or are rigidly framed to columnsmay be proportioned for nine-tenths of the negative moments produced by the factoredgravity loading at points of support, provided that the maximum positivemoment is increased by one-tenth of the average negative moments. This reductionis not permitted for hybrid beams, members of A514/A514M steel, or momentsproduced by loading on cantilevers. If the negative moment is resisted by a columnrigidly framed to the beam or girder, the one-tenth reduction may be used in proportioningthe column for combined axial force and flexure, provided that the axialforce does not exceed c times 0.15A g F y ,whereA g = gross area, in. 2 (mm 2 )F y = specified minimum yield stress, ksi (MPa) c = resistance factor for compressionLRFD Specification for Structural Steel Buildings, December 27, 1999AMERICAN INSTITUTE OF STEEL CONSTRUCTION