Parameter Determination Of RC Frame Model With Infill Walls For City Earthquake Disaster Simulation

With the proceeding of the urbanization,population and social wealth are aggregating in cities,which,meanwhile,are becoming intricate and fragile.Once an earthquake strikes near cities,it would bring about serious consequences.To make a better research for the city earthquake disaster mechanism and disaster prevention measures,it is necessary to apply modern computing science and structural analysis techniques to establish a city-scale earthquake disaster simulation system on the basis of physics principles and refined models.For the development and the application of the system,the algorithm for automatic modeling and the method for determination of model parameters are essential.This thesis focuses on developing a method for parameter determination of RC frame structure models,taking the effect of infill walls into account.The main works of this thesis are as follows:(1)A method is proposed for parameter determination of trilinear story shear-drift skeleton curve of RC frames without infill walls.Apply fiber element to model a series of typical RC frames designed in accordance with the current codes and then have a pushover analysis on them.A series of inter-story constitutive curves of structures with various fortification intensity,number of stories,number of bays and bay width are obtained.With statistical approaches,the parameters of bearing capacity and drift of the characteristic points on the skeleton curve are analyzed,including the yield,the peak and the ultimate points.(2)A diagonal compressive strut model for infill walls is suggested for the elastoplastic analysis on RC frame structure,and its effectiveness is verified with quantities of tests results.Relavant estimation formulas for the stiffness and strength of single strut model for infill walls are collected.By comparing the estimated results with the results of several domestic tests on RC frames with infill walls,appropriate equations are selected for estimating the strut model's stiffness and strength related to the diagonal tension failure mechanism.Then the form and the method to determine the parameters of the strut model are suggested,and its effectiveness is verified through tests result.(3)A method is proposed for parameter determination of trilinear story shear-drift skeleton curve of RC frames with different types of infill walls.The strut models of infill walls are inserted to a series of RC pure frames with various fortification intensity,number of stories,number of bays and bay width,in order to analyze the influence of different layouts of infill walls on the mechanical performance of RC frames and take infill walls with holes into consideration.Finally,the parameter determination and collapse mechanism of RC frames with infill walls are investigated and studied.(4)A method is proposed for modeling RC frames with different layouts of infill walls.The wall ratio and the hole ratio are used to represent various layouts of infill walls in each story of structures.These two parameters are applied as variables to determine the parameters of the skeleton curve of RC frame with infill walls.Finally,a workflow is summerised for the parameter determination of the trilinear skeleton curve of RC frame with infill walls.The parameters required for this workflow are clear and simple,and the method could be applied for simulating the seismic response of most normal RC frames in cities.