Experimental Study On Impact Resistance Of FSJ Concrete Columns

Non sintered fly ash ceramsite is a lightweight aggregate mainly made of fly ash,mixed with activators and other chemical agents,wrapped in a new process and naturally hardened.As an important branch of lightweight aggregate concrete,lightweight concrete prepared from non sintered fly ash ceramic particles and ceramic sand is a new type of building material with excellent properties such as lightweight concrete and green environmental protection;This article uses FSJ to represent non sintered fly ash ceramic particles.There is currently limited research on the lateral impact performance of FSJ concrete columns.In practical engineering,most concrete columns are subjected to a certain axial pressure,and the axial load value has a significant impact on the impact resistance performance of concrete components.Therefore,when studying the impact resistance performance of FSJ concrete columns,the influence of different axial compression ratios on the impact resistance performance of components should be considered.Only in this way can the practical application of this material be promoted.On the basis of our research group’s research on the basic mechanical properties of FSJ concrete materials,the lateral impact resistance of FSJ fully lightweight concrete columns was studied through drop hammer impact tests.The dynamic response of FSJ column components under lateral impact loads under different axial compression ratios was numerically simulated using finite element software ABAQUS.By applying different axial forces to the specimens in advance,the dynamic response of concrete components under lateral impact loads under different axial compression ratios was obtained.And compare with the experimental results to verify the reliability of numerical simulation,providing a basis for subsequent parameter expansion and engineering application refinement analysis.The specific research content and conclusions are as follows:(1)Study on basic mechanical properties of FSJ concreteConduct compressive strength,flexural strength,splitting tensile strength,and elastic modulus tests on the prepared C30 grade FSJ concrete,and determine the full stress-strain curve of the material under uniaxial compression.Analyze the basic mechanical properties and cracking failure characteristics of FSJ concrete,providing a theoretical basis for the study of the impact performance of FSJ concrete columns.(2)The experimental research variables for the impact resistance of FSJ lightweight concrete columns are: axial compression ratio,longitudinal reinforcement ratio,hoop ratio,and steel fiber ratioA high-performance drop hammer test system was used to conduct impact tests on 7 FSJ concrete columns,and high-speed cameras were used to record the entire failure process of the 7 concrete columns.Based on the variables of FSJ concrete column impact test research,the focus is on analyzing the fracture morphology and crack development pattern of FSJ concrete column under impact load,and comparing and analyzing the time history curves of impact force,mid span displacement,and steel strain measured in FSJ concrete column lateral impact test.(3)Finite element simulation analysis using ABAQUSSimulate the lateral impact test of FSJ concrete columns using ABAQUS finite element analysis software,and compare the column damage cloud map,impact force time history curve,and mid span displacement time history curve in the simulation results with the test results.The results indicate that the finite element simulation results are in good agreement with the experimental results,thus verifying the feasibility of the simulation analysis method.