Damage Analysis Of All-lightweight Concrete Based On AE Parameters

Lightweight aggregate of porosity,smaller elastic modulus and low cylinder compression strength,which lead to multiple damage and damage mechanism different from ordinary concrete.In view of this,the paper analyzed and studied the damage law of the all-lightweight shale ceramsite concrete(Referred to as ALWSCC)and steel refinorced all-lightweight shale ceramisite concrete(Referred to as SRALWSCC)beam based on the acoustic emission parameters,explains the damage mechanism of the ALWSCC.Specifically,the main research contents and results are as follows:(1)Through the springback and elasticity modulus tests,the change law of concrete strength after the shale ceramsite join was analyzed.The relationship of the effective elastic modulus of shale ceramsite,matrix mortar matrix,elastic modulus of concrete,and the influence of the deformation and strength of shale ceramsite concrete was discussed and the foundation for the analysis of the damage for the rest of the article was laid;(2)To carry out the uniaxial compressive acoustic emission tests of all-lightweight shale ceramsite concrete and mortar matrix.The paper analyzes the change rule of energy,cumulated energy,ringing countings,cumulated ringing countings,amplitude and duration of stress and discusses the relationship between the peak frequency and energy as well as three different stress levels under the range of the acoustic emission signal energy distribution.The angle of acoustic emission parameters explains the damage mechanism of ALWSCC;(3)To carry out three-point bend acoustic emission experiments of steel refinorced all-lightweight shale ceramisite concrete beams and based on the parameter analysis method,this paper analyzes the energy,accumulated,cumulative number counting ringing and ringing,amplitude changing with the acoustic emission signal arrival time and discusses the distribution and peak frequency range of different failure mechanisms;(4)Through the analysis of acoustic emission events number for ALWSCC and the energy,ringing count of SRALWSCC beam,a continuum damage model of acoustic emission cumulated events and the damage curve with characterization by energy and ringing count was established;(5)Obtained a fitting tacoustic emission activity function based on damage mechanics and acoustic emission rate process theory,the changing rule of the parameter m for the different stages of loading rate analyzed,the damage early warning method according to the rate parameter m of SRALWSCC beams are presented.