Study On Mechanical Properties Of Ribbed Elements Of Multi-ribbed Composite Wall Under Lateral Pressure Of Grain

The warehouse is one of the leading positions in grain storage type,but for a long time,grain warehouse building structure system with traditional brick masonry structure,the masonry workload big,construction period is longer,the shortcomings of high difficulty of construction quality control.Multi-ribbed composite wall structure is a prefabricated structure system,wallboard composed of concrete and embedded filling block.Into the granary building,can overcome the disadvantage of traditional masonry structure,realize the granary building of standardized design,industrial production,mechanical construction,speed up reform and innovation in the form of granary building wall structure.Different from the civil building wall,the multi-ribbed composite wall of bungalow mainly deforms outside the plane under the lateral pressure of grain.In this paper,the ribbed element composed of the concrete ribbed composite wall slab and the filling blocks in the bunker is taken as the research object,and the tensile fracture performance test and shear slip performance test of ribbed element are designed and carried out.Non-contact measuring instrument is used to collect data,and various mechanical parameters of the block-concrete bonding interface are calculated.Based on the cohesion model,the ribbed element of ribbed composite wall slab is theoretically analyzed and the finite element numerical simulation is carried out.(1)In view of the tensile crack of ribbed composite wall panels when the bond interface of ribbed units is broken under the lateral pressure of grain,block-concrete splitting tensile test and three-point bending beam test are designed to analyze the failure modes of the two specimens.The influence of interface materials of different strength levels on the tensile strength of the bond interface is studied through the splitting test.The fracture toughness and crack initiation toughness of the block-concrete bond interface are calculated according to the three-point bending beam test.(2)Considering the lateral pressure of grain,the multi-ribbed composite wall panel floor space in the cell filling block with crushed concrete ribbed lattice trend,design of the block and concrete launched double-side shear test,the specimen shear failure occurs in the bonding interface failure pattern,bearing capacity,and the interface of different strength grade material effect on the properties of adhesive interface shear slip.(3)The material composition of the bond interface was analyzed from the microscopic point of view,the applicability of the cohesive force model was described and the basic principle of the model was introduced in detail.The tensile failure fracture energy and the tensile stiffness of the bond interface were determined by the three-point bending beam test and the splitting test,respectively.Fitting out,under different strength of interface material bonding interface shear slip constitutive relation,the shear damage fracture energy and adhesive interface shear stiffness;On this basis,by three point bending beam and double shear test,the measured interface damage stress value,shear,and application of Mohr strength theory draw don’t stress circle,fitting of bond interface failure envelope,the interface strength of materials as variables,study the development trend of the bond interface failure under different stress state.(4)The cohesion model of multi-ribbed composite wall rib unit damage distribution of the bonding interface and fracture finite element numerical simulation,the key parameter calculation and analysis.By defining the tension-displacement relationship and the initial damage criterion of the model,the cooperative stress mechanism of the concrete ribs and blocks was studied,and the influence of the bond interface on the mechanical properties of the multi-ribbed composite wall panels of the barn was analyzed.The rationality of the finite element model and the constitutive relationship between the selected materials and the interface was verified by comparing with the experimental results,which provided a theoretical basis for the structural design of the multi-ribbed composite wall panels of the warehouse.