Experimental And Theoretical Study On Flexural Behavior Of Prefabricated Ribbed Composite Wall Panels

With the development of the national economy and the disappearance of the demographic dividend,the assembly building has become the development direction of China's construction industry.Among all kinds of assembly building systems,steel structure building is an ideal assembly building system,which can well realize the production of prefabricated chemical plants.At present,the key factor that restricts the development of steel structure buildings is the supporting envelope system,especially the external wall panels,which always plague the development of steel structure buildings.Compared with traditional aerated concrete blocks,composite wallboard can be manufactured by factory assembly line,which is convenient to install and has short construction period.It is an ideal enclosure system for steel structure building system.Composite wallboard is more used in our country as a kind of non-load-bearing external wall panels and assembly steel structure system.The smaller the self-weight of composite wallboard is,the more advantageous it is to the seismic design of the structure and the design of the wall-board connection joint.Therefore,light composite wallboard has always been the focus of composite wallboard research.The traditional composite wallboard is sandwich plate structure.In this paper,the cross-section optimization of flat composite wallboard is carried out,and some concrete in flat concrete layer is removed to form ribbed concrete surface layer,so as to reduce the weight of composite wallboard.In order to investigate the flexural performance of new ribbed composite wallboard,the flexural test,theoretical derivation and finite element analysis of new ribbed composite wallboard under uniform load are carried out in this paper.Based on the static bending load test of the traditional plate composite wallboard and the new ribbed composite wallboard,the mechanical properties of the new ribbed composite wallboard,such as cracking load,ultimate load,deflection and crack development,are studied.The bending performance of the new ribbed composite wallboard is compared with the traditional plate composite wallboard,and the optimized weight-reducing ribbed composite wallboard is analyzed.The experimental results show that the new ribbed composite wallboard can effectively reduce the weight of the traditional composite wallboard.Under uniform load,the new ribbed composite wallboard has similar bending behavior with the traditional flat composite wallboard.Compared with the traditional plate composite wallboard,the bending capacity of the new ribbed composite wallboard is reduced,and the smaller the self-weight of the new ribbed composite wallboard,the smaller the bending capacity of the specimens.However,compared with the extent of the quality reduction,the reduction of the bending capacity is much lower than that of the quality reduction.Based on the analysis of test data of bearing capacity,strain and displacement at the bottom of the slab,and on the assumption of traditional mechanical bending theory,the theoretical model of bending resistance is deepened,and the formulas for calculating the cracking load and ultimate load of the new ribbed composite wallboard are put forward.Based on the plastic hinge theory,the deflection calculation formula of the new ribbed composite wallboard is proposed.The theoretical results are in good agreement with the experimental values and can be easily applied to the design of practical projects.The finite element analysis software ABAQUS was used to simulate the composite wallboard,and the simulation results were compared with the experimental data and theoretical analysis.The rationality of the finite element model was verified.The parameters of the rib angle were analyzed successively,and the optimal rib angle was proposed.