Report - PEER - University of California, Berkeley

evisions were made in structural design requirements because the structural designregulations were already in a performance-based format. The capacity-demandspectrum method was introduced in seismic design in the 2000 revision.Structural calculation methods are outlined in Section 8: Structural Calculation.Structural calculation for buildings, less than 60 m in height, shall follow either (a)the allowable stress calculation (old procedure) or (b) the ultimate strength calculation(new procedure) or (c) the structural calculation set forth by MOLIT to producestructures as safe as the allowable stress calculation or the ultimate strengthcalculation.Three performance objectives are defined for the evaluation and verification ofperformance (response) under (a) gravity loads, (b) snow loads, (c) wind pressures,and (d) earthquake forces; i.e.,(1) Maintenance of building serviceability under permanent loading conditions(dead and live loads),(2) Prevention of structural damage under frequent loading conditions (snow,wind and earthquake events corresponding to a return period ofapproximately 50 years), and(3) Protection of occupants’ life under extraordinary loading conditions (snow,wind and earthquake events corresponding to a return period ofapproximately 500 years.The types and amplitudes of loads and external forces, the allowable stress and thenominal strength of materials are outlined in the law enforcement order.3.5 Allowable Stress CalculationThe allowable stress calculation is briefly introduced in this section.The stress in any part of structural members under the combination of dead andlive loads (long term loads) shall be less than the allowable stress of constructionmaterials set forth for long-term loading. The allowable stresses for the long termloading are specified much lower than the elastic limit or creep limit of materials;e.g., allowable compressive stress of concrete is one-third of the nominal compressivestrength, allowable shear stress is one-thirtieth of the nominal compressive strength,and allowable tensile stress of reinforcing bars is two-thirds of the nominal yieldstress. The unit weight of materials for the evaluation of dead loads and the unitweight associated with room use for the evaluation of live loads are specified. Theserviceability of the building shall not be impaired by the deformation and vibrationcaused by the long term loads, the serviceability should be examined by the structuralcalculation set forth by MOLIT Notification 1459.The stress in any part of structural members under the combination of (a) dead,live and snow loads, (b) dead, live loads and wind forces, and (c) dead, live andearthquake forces shall be less than the allowable stress of construction materials setforth for short term loading. The allowable stresses for the short term loading arespecified lower than or equal to the elastic limit of materials; e.g., allowable524