Research On Compressive Performance Of Concrete Sandwich Composite Wall Panel

Concrete sandwich composite wall panel is a kind of composite wall panel which combines thermal insulation performance and structure.Because of its light weight and good thermal insulation performance,it has been widely used in engineering practice.The study and promotion of the wall panel not only meet the standards and requirements of building energy conservation,but also have important significance.The research on compressive performance is an important part of the wall panel.Through the study of two groups of wall panel test piece,the paper studies the bearing capacity of this type of wall panel under the action of high-thickness ratio and eccentricity.Combined with finite element analysis,the failure mechanism of wall panel under two factors is obtained,and the guidance for the optimization of this type of wallboard is proposedBy means of experimental research and theoretical analysis,the following conclusions are summarized:(1)Under the axial pressure of the concrete sandwich composite wall panel,the stress distribution of the surface layer of the concrete wallboard is not uniform.When the load is relatively small,the middle of wall panel's stress is relatively large;with the increase of load,the concrete surface layer of the end of wallboard is deformed,the stress is redistributed,and the maximum stress is transferred to the ribs on both sides;finally,the stress at the rib position on both sides reaches the concrete compressive strength,and the damage first occurs,this moment,the load is transferred to the central wall of concrete surface layer,and then the local concrete surface layer is partially unstable and destroyed,and the entire test piece loses its bearing capacity and is destroyed(2)The following formula is the calculation formula of bearing capacity of composite wall panel under axial compression Nu=?0Acfc In the formula,?0 is stability coefficient of axial compression members:?0 = 0.6-0.016H0/h(3)Under the action of eccentric load,the stress distribution of the concrete layer of the concrete sandwich composite wall panel is not uniform,and the stress at the two ends of the wall plate eccentric force is relatively large,that is to say,the stress at the rib of the wall plate is always relatively large.The ultimate compressive strength of concrete in the rib on the compressive side of the specimen is reached,and the damage first occurs,at the same time,the concrete surface layer on the side wall of the eccentric force is also crushed and detached,the test piece loses its bearing capacity and is destroyed,and the other side of the test piece is pulled to produce horizontal cracks.(4)The following formula is the calculation formula of the bearing capacity of composite wall panel under eccentric pressure:Nu=??0Acfc In the formula,? is eccentric bearing capacity influence coefficient:?=1.0-d/h(5)Through finite element analysis,the stress distribution and stress mechanism of the specimen are consistent with the failure mode of the specimen,and the bearing capacity analysis value is basically consistent with the test value,it proves the assumptions made during the analysis and the correctness of the model.(6)The enlarged end of the end of the test piece will have a greater impact on the bearing capacity of the test piece.In actual engineering,the thickness of the solid concrete at the lower end of the wall plate should be appropriately increased or the cast-in-place concrete floor should be used,it is more beneficial to the force of the wallboard.