Research Of Early Shrinkage Properties On A New Type Of PC-GRC Lightweight Composite Wall Panel

The progress and development of the times have brought many changes to our lives such as the development of Building industrialization and prefabrication of PC Building components in recent years.Compared with the traditional construction mode,It abandoned the traditional model of artificial architecture,which is a groundbreaking historic breakthrough to replace the traditional model with advanced science and technologies.PC Building components revolutionizes the way buildings that have been built thousands of years of brick as the main material are replaced by standardized components and industrialised building patterns.External wall is always treated as a key part of building structure.With the gradually development of the times,the direction of prefabricated composite wall is developing.Nowadays,the traditional prefabricated wall uses the external wall for the decorative outer layer,but the installation is complicated and complicated,and it is easy to crack,which does not meet the requirements of building industrialization.In the process of actual decoration of buildings,the connection between decorative materials and panels is not reliable.Many decorative floors of external walls of buildings will fall off in a large area,which will not only directly affect the aesthetic appearance of buildings,but also be prone to personal danger.In this paper,In the National key R&D Project of the Thirteenth Five-Year Plan,"High-efficiency construction of prefabricated concrete industrial building",is presented in this paper.Under the background of the key technology research and demonstration "the new decorative material and the composite thermal insulation wall panel integrated production and installation key technology" background,aiming at the construction efficiency of the exterior decoration wall of the present prefabricated building,In this paper,a new type of PC-GRC lightweight composite wall with load-bearing,decorative and lightweight properties is studied.Although this new type of PC-GRC lightweight composite wall has many advantages that the external wall does not have,However,PC-GRC wall is prone to crack due to its dry shrinkage assembly,cracks will reduce the performance of the wall,and the early shrinkage of concrete is one of the causes of cracks.Most of the previous studies mainly analyzed the impact of the early shrinkage of single concrete material on the cracks.The effect of the interaction between two different materials on the crack has been neglected.On this basis,this paper mainly discussed the followingwork:A large number of related research results at home and abroad are read for reference,and the formation mechanism of shrinkage cracks in concrete,the crack control concept,the causes of cracks of GRC materials and the preventive measures are introduced.Five groups of wall panels were constructed and the early strain changes of each specimen were measured by strain measuring instrument.In this paper,the early strain variation of five groups of wall panels is studied,and the law of strain variation of free shrinkage and constraint shrinkage wall panels and the influence of different interface treatment methods on wall strain changes are analyzed.Based on the equivalent temperature difference method,the shrinkage strain of the new PC-GRC plate was analyzed by using the large scale finite element software ABAQUS,and the thermal analysis method in the numerical simulation.The calculated results were compared with the actual experimental values.The numerical simulation method is verified.