| Prefabricated ECP is widely used in internal wall,external wall,wall,acoustic wall and other building facilities.It is an important part of prefabricated building.ECP is still in its infancy in China,and its production equipment mainly depends on imports.Related enterprises of the design,manufacture,assembly,debugging,and system integration ability is weak.Enterprises in the extrusion forming key technology,extrusion mechanism research,core equipment research and development and manufacturing investment in research and development is not deep enough.In addition,there are few researchers in this field,and the domestic ECP extrusion forming production line equipment is not mature,resulting in the current production efficiency is not high,the plate surface density is too high,seriously hinder the promotion and development of ECP.So for prefabricated ECP extrusion forming key technology research and optimization analysis is very necessary.(1)According to the analysis of the composition and properties of ECP material,it is concluded that the rheological model conforms to the Bingham rheological model.The viscosity and yield value of sand powder were measured by cross-flow plate method.The motion equation and motion characteristics of the material in the vacuum extruder are analyzed.The common defects in extrusion process are summarized and the improvement measures are put forward.(2)Aiming at the current problem of high surface density of ECP plates,based on ABAQUS's concrete damage plasticity model theory,the establishment of the ECP plate CDP model was completed.ECP plate unit test specimens with three different plate cross-sectional pass types: rectangle,round hole and square round hole The numerical simulation of the plate compression test is completed.The simulation results show the stress cloud diagram,deformation diagram and load displacement diagram of each hole-shaped plate unit body.The structure of the rectangular unit body specimen is selected by comparing the simulation results.Finally,set the void rate of the rectangular unit body specimen as an optimized variable,and complete the numerical simulation of different void rate models with reference to the numerical simulation of different hole plate unit bodies,and analyze the void rate value of the rectangular unit body specimen model.The optimal range of the ECP sheet not only meets the standard compressive strength value,but also obtains a good ECP sheet surface density value.(3)Referring to the actual conditions prior ECP sheet vacuum extruder screw auger blades,in ANSYS finite element simulation thereof.Through the analysis of the simulation results of the spiral cutter,three optimization variables are determined,and feasible change parameters are set for the three variables based on experience and practice.Based on the orthogonal simulation experiment and genetic algorithm,the parameters of the spiral reamer are optimized,and the result is helpful to improve the stress and strain of the spiral reamer.(4)Aiming at the problem of uneven size of sand and powder condensate in the current mixing process of ECP plate sand and powder material,the simulation analysis of the mixing process is carried out by coupling discrete element software and finite element analysis software.The blending degree analysis uses the least square method to simulate the experimental values and perform approximation processing between the function images.Through function fitting,the calculation formulas of the volume of sand powder condensate,mixing time and processing environment temperature are obtained and verified.By comparing the theoretical value obtained by the calculation formula with the experimental value in the same image,it is concluded that the function fitting is basically consistent. |
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