近断层脉冲地震动对高烈度抗震设防区高层钢框架-支撑筒结构的影响分析OA

To analyze the impact of near-fault pulse-like ground motions on high-rise steel structures,a 22-story steel frame-braced core structure was used as an example.A total of 97 near-fault pulse-like ground motions were selected,and their pulse components were removed to obtain 97 non-pulse-like ground motions.These 194 ground motions were input into the example structure to conduct elastic-plastic analysis,and the amplification effect of structural seismic response under near-fault pulse-like earthquakes was analyzed.Analysis results indicate that average amplification coefficients of story shear force,story drift and story displacement(δV,ave,δdri,ave,δdisp,ave)exceed 1.0,with maximum values of 1.18,1.38,and 1.38,respectively.Near-fault pulse-like ground motions significantly affect structural displacements.The amplification coefficients are influenced by the pulse period,fault type,fault distance and peak ground acceleration(PGA).As the pulse period increases,the amplification coefficients decrease with fluctuations.For shorter fault distances,the amplification coefficients gradually increase by up to 10%.Under the same PGA,strike-slip faults exhibit higher amplification coefficients than reverse faults,with a maximum increase of 24%.For an exceedance probability of 63%,the estimated shear amplification coefficient(δV,e)decreases with increasing PGA,with a variation range of[1.12,1.28],while the estimated story drift and displacement amplification coefficients(δdri,e and δdisp,e)increase with increasing PGA,both with a variation range of[1.32,1.50].At 2%exceedance probability,δV,e decreases with increasing PGA,with a variation range of[1.17,1.38],while δdri,e and δdisp,e increase with increasing PGA,with variation ranges of[1.43,1.66]and[1.44,1.66]respectively.Based on the exceedance probabilities for frequent and rare earthquakes,for the example structure,the structural response amplification coefficient can be taken as 1.32 under frequent earthquake.Under rare earthquake,the amplification coefficients of story shear force and structural displacement are 1.25 and 1.50,respectively.