Experimental Study And Finite Element Analysis On Mechanical Performance Of Modified Perlite Concrete Components

As a new type of lightweight building materials in recent years, modified perlite concrete has been widely applied in practical engineering and created remarkable economical and social benefit. However, the experimental research and theoretical analysis on the mechanical properties of the material and its components are few at present. Theoretical research obviously lags behind engineering application, and it has seriously restricted its further development and application. Therefore, based on the test of mechanical properties of modified perlite concrete, the paper designs the static loading test of modified perlite concrete slabs and modified perlite concrete beams, studies the bending and shearing failure process and failure mechanism of modified perlite concrete components, and the modeling analysis of modified perlite concrete components is carried out by finite element software ABAQUS. This will provide experimental basis and theoretical guidance for the application and design analysis of modified perlite concrete components. The contents of this dissertation are listed below:(1)Mechanical property test of modified perlite concrete: Based on the 400 grade modified perlite concrete materials, the cube compressive strength test, prism compressive strength test, static compressive elastic modulus test of modified perlite concrete block and stress-strain curve test are carried out to determinate the mechanical properties and parameters of modified perlite concrete, this will provide basic data of experimental analysis and finite element modeling of component. Finally, it simulates the prim compressive strength test of modified perlite concrete based on the concrete damaged plasticity model(CDP model) owned by ABAQUS, and validate the accuracy and effectiveness of finite element model.(2)Static loading test of modified perlite concrete slab: Through this static loading test of 8 modified perlite concrete slabs with different reinforcement ratio and different production practices, it studies the mechanical behavior and failure models under uniformly distributed load(simulated by eight-point loading), and analyses the effect of reinforcement ration, stirrup ratio, cement mortar composite layer and steel skeleton on the mechanical properties of modified perlite concrete slabs, and determines the method to improve the shear capacity of modified perlite concrete slabs.(3)Static loading test of modified perlite concrete beam: Through two-point loading test of 6 modified perlite concrete beams with different reinforcement ratio and different section dimension, the whole process of crack appearance, development and failure of pure bending or bending shear section, failure characteristic and failure mechanism are studied. It has important significance to analyses the mechanical properties, improve the failure characteristic of components and enlarge the applying scope of modified perlite concrete.(4)Finite element simulation analysis of modified perlite concrete components: Based on the CDP model owned by general finite element software ABAQUS, the paper constructs modeling analysis of partial modified perlite concrete slabs and beams. By contrasting the stimulant result to the test result, study the coincidence, analyses the reason of the differences, discuss the accuracy and feasibility of model, and point out the shortcomings of model. This will provide the basis for engineering application and finite element model of modified perlite concrete components.(5)Influence of modified perlite concrete slab on seismic performance of structure: Taking two-storey thin-wall steel structure frame in eight degree of aseismatic design area as an example, the paper establishes two finite element models for adopting modified perlite concrete slab and lightweight aggregate concrete slab as floor by ABAQUS. The elastic-plastic time-history analysis under earthquake are constructed, and the top displacement, interstory displacement, story drift, base shear and tensile damage of floor slab under earthquake are compared, and the improving effect of modified perlite concrete slab on seismic performance of structure are studied.