Study On Flexural Mechanical Properties Of Autoclaved Aerated Concrete Exterior Wall Panel

Reinforced autoclaved aerated concrete(ALC)panel is made of industrial waste containing siliceous materials and calcareous materials,and is made of various processes such as gas forming,cutting,autoclaving and other processes.It is a porous silicate insulation wall material.It has the advantages of light weight,high strength,good thermal insulation,good fire resistance and convenient installation.It is considered by the domestic construction engineering community to be the most ideal wall material for steel structure.However,the application in the past few decades shows that the application of autoclaved aerated concrete panel retaining structure in high-rise steel structures has unavoidable problems.Among them,the cracking and seepage of ALC board enclosure system is one of the main reasons hindering its promotion.Therefore,it should be ensured that the autoclaved aerated concrete siding has sufficient strength against cracking under high wind load and ensures that the plate does not suffer from ultimate bearing capacity damage.In addition,China’s product standard "autoclaved aerated concrete panel" GB15762-2008 has clear provisions on the cracking capacity and ultimate bearing capacity of autoclaved aerated concrete siding except the inner partition wall.In this paper,the reinforced aerated concrete exterior wall panel is the research object,and the calculation method of cracking moment and ultimate bearing capacity is studied,which provides theoretical support for the bearing capacity design of autoclaved aerated concrete slab.The details are as follows:Considering the influence of prestress caused by temperature in the autoclaved aerated concrete slab,the drying shrinkage of the aerated concrete material and the plastic development of the section of the wallboard,to the wallboard cracking caused by bending.Specifically,the prestress in the panel due to temperature is calculated,and the prestress in the plate is reduced by combining the drying shrinkage characteristics of different kinds of autoclaved aerated concrete materials,and the section plasticity development coefficient is calculated according to the tensile properties and cross-section characteristics of the autoclaved aerated concrete panel.Finally,the calculation method of the cracking moment of the wallboard is established by the ultimate tensile strain of the concrete in the tension zone of the wall panel.According to the reinforcement law and section characteristics of the autoclaved aerated concrete panel in practical application,within a reasonable range,The calculation formula issimplified to obtain a calculation formula related only to the tensile strength,section size and reinforcement ratio of the material,The formula agrees well with the experimental data.Through the analysis of the existing test results of autoclaved aerated concrete panels,combined with the calculation theory of ordinary reinforced concrete members,the failure modes under the ultimate bearing capacity of autoclaved aerated concrete panels are classified as bending failure and bending shear failure,combined with The characteristics of autoclaved aerated concrete materials are analyzed by force analysis under different failure modes,and the ultimate bearing capacity calculation method under bending failure and bending shear failure modes is obtained.The experimental results show that the corresponding formulas can accurately calculate the ultimate bearing capacity of members.