Abstract:Based on the shaking table test of SRC special-shaped column space frame model,the spectrum characteristics,eccentric dynamic response and nonlinear response law of the model structure are studied.The results show that,under the action of 3-dimensional seismic effect,the Y-direction and X-direction horizontal torsion coupling phenomena occur in the high-order vibrationmode of the model structure,and the vibration modes are X-direction translation,Y-direction horizontal torsion,Z-direction vibra-tion,torsion and Y-direction translation in tumn;under the action of strong earthquake,the natural vibration frequencies of X-direc-tion,Y-direction,Z-direction and torsion decrease by 31.02%,30.10%,39.72%and 30.09%respectively;the zero point,theimaginary part and the peak point of the real part curve of the frequency responsefunction of the model structure gradually move tothe low frequency with the increase of the load holding time,the structural damage gradually accumulates,thesifness continuous-ly degenerates,the dynamic stifness is close to the static stiffress,and the structural deformation is great.Through the numericalanalysis,it can be seen that when the eccentricity is certain and the horizontal torsion period ratio is constant,the peak points of natural frequency ratio and horizontal torsion coupling coefficient of eccentric structure is obviously pushed back compared with that ofsymmetrical structure;under the action of strong earthquake,the weak layer of the model structure with eccentricity less than 0.1appears in the middle and lower part of the structure,and the weak layer of the model structure with eccentricity greater than 0.3 appears in the upper part of the structure;with the increase of eccentricity,the model structure reaches the performance point in advance,and the capacity spectrum curves at all intersections are not in the obvious decine section of bearing capacity.Therefore,the seismic performance of the structure meets the requirements.