Seismic Analysis Of K8Latticed Shell Considering The Accumulated Damage Effects Of Lower Concrete Support

Layer spherical reticulated shells is widely used in large-span spatial structuresfor its rational form and graceful structure, It is particularly important to study itsseismic performance. In this paper, I systematically analyzed the force characteris-tics of K8reticulated shells with the lower support in order to get a betterunderstanding of their seismic performance. To get a more precise model, I hasdeveloped the concrete damage constitutive subroutine, which makes it possible toconsider the concrete material nonlinearity effect in ABAQUS space beam elementsimulation. Through comparative analysis has shown us the great influence of thecumulative damage of concrete in support structures on earthquake response. Takinginto account the lower supporting cumulative damage of concrete cases, I summari-zes three failure modes of the structure, and made a brief analysis of each failuremechanisms. Finally, I analysis the structural parameters’ impact on the failure loads.Main tasks and conclusions include the following three aspects:First, I developed a concrete damage constitutive explicit subroutine used inABAQUS space fiber-beam elements, The subroutine contains the "Design ofConcrete Structures" skeleton curve and the Kent-Park model loading and unloadingprinciples, and verified the accuracy of the subroutine on the level of the units andcomponents. Subroutine was developed to enable the use of ABAQUS beam spaceelement simulation concrete, considering material nonlinearity.Second, To improve ABAQUS/CAE modeling efficiency, I developed thetransformation interface of ETABS model to ABAQUS model. It gives us a efficientmodeling method of frame shear wall structure in ABAQUS/CAE through theInterface program, which address the main challenges include the equivalent modeltransformation reinforcement, floor and wall mesh uncoordinated treatment.Third, Comparative analysis points cumulative damage on the lower supportingconcrete structures makes important influence on earthquake response. Then Icombined the up-shell structure damage parameter and the low-supporting structuredamage parameter, and established the structure failure criteria, and applied to thedetermination of structural failure load. After considering the cumulative damage inthe lower supporting concrete cases, I conducted different parameters with lowersupport K8reticulated shell under the dynamic analysis through the entire history, Isummed up the structure of three types of failure modes, and made a brief analysisof each mechanism. Finally, through parameters analysis, we got the regulareffective pattern of the support stiffness, span ratio and the roof loads on thestructural failure load.