Study On Damage Of Multi-Ribbed Composite Wall Cell After High Temperature

In order to promote the reform of assembly-type buildings and meet the needs of the construction industry transformation,multi-ribbed composite wall structure system as an ecological,energy-saving and shock-absorbing assembly type building has been widely used.However,the occurrence of fire reduces the using performance of building and seriously threatens the safety of human and property.Much progress has been achieved in previous study,but further research on high temperature damage problem of multi-ribbed composite wall cell should be done.Using MATLAB as a platform,detailed research is made on temperature field,local damage index and general damage index of multi-ribbed composite wall cell after high temperature.The main contents are as follows:(1)According to the theory of heat conduction,the problem of solving the temperature field of multi-ribbed composite wall cell is simplified to one-dimensional unsteady heat conduction problem.Due to the different fire conditions,different calculation programs of the temperature field are worked out.Establishing the numerical analysis to specific multi-ribbed composite wall cell and comparing the simulation results with the program calculation results to verify the correctness of the program.(2)Based on the inner mechanism of damage after high temperature,the elastic-plastic damage rigid frame-bar model was presented and the high temperature damage variables of the subunits in the model were defined.The high-temperature damage analysis program MRCS-T was developed.Through this program,the local damage value of multi-ribbed composite wall cell after high temperature can be calculated,which will lay the foundation for the general damage assessment.(3)General damage index was proposed through energy method.Using the local damage value of multi-ribbed composite wall cell after high temperature,a general damage index which can be used for evaluating was constructed.Referring to the division method of RC damage state,five performance levels for damage process of multi-ribbed composite wall cell were determined and corresponding damage limit value were given,which provides the basis for the post-fire evaluation of multi-ribbed composite wall cell.