Research On The Influence And Mechanism Of Raw Materials On The Performance Of Inner Panel Of The Composite Exterior Wall Panel

The rapid development of industrialization and urbanization in China not only consumes a lot of resources and produces a lot of waste,which has a great impact on the environment,but also promotes the promotion of prefabricated buildings.In this paper,the preparation technology of glass fiber reinforced recycled fine aggregate composite exterior wall panel inner panel is studied,which can not only utilize solid waste,but also meet the needs of prefabricated building for prefabricated wall panel.This studies the influence of recycled fine aggregate gradation and mineral admixture composition on the performance of self leveling mortar for wall panel,determines the proportion of self leveling mortar,and puts forward the mechanism of mineral admixture.Then the effects of fiber mesh weight,laying layers,mineral admixture and different pulp to bone ratio on the flexural strength,impact resistance and dry shrinkage resistance of the panel were studied,and the mechanism of the effects was analyzed.By comparing fuller method,K method and I method,the influence of recycled fine aggregate gradation on mortar strength is found.When the aggregate amount is fixed,the mortar strength is higher when the content of small particles below 0.3mm is less.The ratio of coarse,medium and fine particles is 51%,25%and 24%.Mix 6%mineral admixture can improve the fluidity of the self-leveling mortar,and at the same time can increase the strength of the self-leveling mortar.Among them,the single slag powder and the mixed fly ash-limestone powder have the best effect.Mineral admixtures did not participate in the hydration reaction during the early hydration of sulphoaluminate cement,and the main hydration products were still AFt and AH₃.With the addition of mineral admixtures,the amount of water involved in the reaction with cement increases without changing the water cement ratio,that is to say,the water cement ratio increases,the total heat release of early hydration heat decreases,and the first and second heat release peaks of hydration reaction delay.The mineral admixtures such as limestone powder can also provide the crystallization site of aft in the reaction,accelerate the crystallization degree of aft,and advance the third exothermic peak of hydration reaction.Laying glass fiber gridding cloth can significantly improve the properties of the panel.The flexural strength,impact resistance and shrinkage resistance of the panel increase with the increase of the number of layers of fiber grid cloth,so 4 layers of fiber grid cloth are selected.There is a synergistic effect between the glass fiber mesh weight and the cementitious material,that is,matching each other.The fiber surface of 100g/m² and 135g/m² fiber mesh cloth is smooth,the mesh hole is small,and it is suitable for the combination of cementitious materials with good cohesiveness and concentrated particle grading,such as slag powder or pure sulphoaluminate cement;the fiber surface of 165g/m² fiber mesh cloth is rough,the mesh hole is large,and it is suitable for the combination of cementitious materials with moderate cohesiveness and large particle size distribution,such as fly ash silica powder.Different mortar-agreegate ratio has certain influence on the properties of fiber gridding panel.Reducing the ratio of mortar to bone reduces the fluidity of mortar and the flexural strength of panel,but it can improve the impact resistance of panel.